(a revision of Bulletin 134)
UNIVERSITY OF FLORIDA
Agricultural Experiment Station
FLORIDA TRUCK AND GARDEN
INSECTS
J. R. WATSON
"N
FIG. 55.-Bean leaf-roller: Adult. Natural size.
(Fla. Agr. Exp. Sta. Bul. 45.)
The Station Bulletins will be sent free upon application to the Experiment
Station, Gainesville
February, 1919
Bulletin 151
CONTENTS
INTRODUCTION .............. -------
ACKNOWLEDGMENTS .-............ --- .....
LIFE HISTORY OF INSECTS...........................-------
INDIRECT METHODS OF COMBATING INSECTS ....
Cultural Methods ..........-- ........ ........
Destroy Wormy Fruit ......................
Trap Crops ...--....--... ---..
Natural Enemies ..------.... ... --....- ..........
DIRECT METHODS OF COMBATING INSECTS.........
Poisonous Insecticides -.....--..... ......
Arsenicals -- -..--.
Liquid Sprays -.......... ..-.........
Dusts .-......... -------
Contact Insecticides .........
Fumigation .........----
H eat ............. .......... .. .....-- .
GENERAL GARDEN INSECTS AND PESTS--.........
INSECTS INJURIOUS TO BEANS .....................
INSECTS INJURIOUS TO LIMA BEANS --....
INSECTS INJURIOUS TO BEETS ...........
INSECTS INJURIOUS TO CABBAGE .............
INSECTS INJURIOUS TO CANTALOUPES ....
INSECTS INJURIOUS TO CARROTS ............
INSECTS INJURIOUS TO CAULIFLOWER ...---...
INSECTS INJURIOUS TO CELERY ............
INSECTS INJURIOUS TO
INSECTS INJURIOUS TO
INSECTS INJURIOUS TO
INSECTS INJURIOUS TO
INSECTS INJURIOUS TO
INSECTS INJURIOUS TO
INSECTS INJURIOUS TO
CORN ..........
COWPEAS ..
CUCUMBERS
DASHEENS
EGGPLANT
LETTUCE ..
MELONS .....
INSECTS INJURIOUS TO MUSTARD ......-
INSECTS INJURIOUS TO OKRA .........-- ...
INSECTS INJURIOUS TO ONIONS ..........-
INSECTS INJURIOUS TO PARSLEY .......-
INSECTS INJURIOUS TO PEAS .................
INSECTS INJURIOUS TO PEPPERS ---.----
INSECTS INJURIOUS TO POTATOES .........
INSECTS INJURIOUS TO RADISHES -..---
INSECTS INJURIOUS TO ROSELLE ........
INSECTS INJURIOUS TO SQUASH .........
INSECTS INJURIOUS TO STRAWBERRIES .
INSECTS INJURIOUS TO SUNFLOWERS ...
INSECTS INJURIOUS TO SWEET POTATOES
INSECTS INJURIOUS TO TOMATOES .....-..
INSECTS INJURIOUS TO TURNIPS ..........
INSECTS INJURIOUS TO WATERMELONS .
PAGE
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S........ ........ 116
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---- ... -------------- 117
..-.-- ---- ..... --- -----...... 117
.. .... ...... 117
---.--- ----. ---------------- 118
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.- ............. 134
-- ---...... .... ................ 134
-- .-- ----- --. 137
-------...... ......... ........... 149
---.... ..-..........: --....... -- 149
.--- ........-............------. 149
-.------....... ------- 149
--.........-.............-- ----- -- 151
..-.. ...... 160
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--......--.......................... 177
--..... ---------180
..-- ..-......----- 180
..... ....... ........................ 180
......... ........ .......--..... 182
-............... --- --.......-- 185
..----- ......---.....------ 186
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---.---------... 199
.. ...... ... ------ .. 199
APPENDIX -----------------.-------................. ....... ..-------- 201
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FLQRIDA TRUCK AND GARDEN INSECTS
BY J. R. WATSON
Truckers and kitchen gardeners, for whom this bulletin
has been especially prepared will find in it the description, with
illustration, the life-history, and a statement of the best meth-
ods for the control of the insects which commonly trouble them.
Altho mites, nematodes, moles, etc., are not insects, they are
discussed in this bulletin as pests of truck and garden crops.
Only those insects are considered which attack crops during
the season they are commonly grown in Florida. The trucker
in this State escapes many insect attacks that trouble the more
northern truckers because he raises many of his crops in the
winter while insect life is somewhat dormant, this dormancy
being due to the comparative dryness of the Florida winter as
much as to the cold. The early fall crops suffer severely be-
cause insect life has been stimulated to rapid development by
the hot, moist summer. However, some insects thrive better
in dry weather and are most troublesome in the spring.
Much of the information in this reference bulletin is pub-
lished for the first time, from records of recent experiments by
the writer; the remainder is compiled from publications made
by this Station, by other stations, and by the United States De-
partment of Agriculture.
The truck or garden crops are named in alphabetical order.
Under each crop named will be found the descriptions and con-
trol measures of the more important insects which attack it.
Insects which commonly attack more than one crop are listed
under each one, but are discussed under the name of the crop
on which they are most commonly found or on which they in-
flict the most serious damage. Cross references point to these
discussions.
Under the heading, General Garden Insects and Pests,"
will be found discussions of several enemies of the garden gen-
erally, being no more severe on one crop than another.
ACKNOWLEDGMENTS
In gathering the material for this bulletin, the writer has
had valuable help from his assistants, A. C. Mason and H. L.
Bulletin 151, Truck and Garden Insects
Dozier, who made the photographs for the original illustrations.
The data on aphids were gathered chiefly by Mr. Mason, and
much of that relating to beetles by Mr. Dozier, who has also
worked out the life history of the okra caterpillar. The photo-
graphs for the major portion of the illustrations were supplied
by the Bureau of Entomology, U. S. Department of Agriculture.
Two were furnished by the North Carolina Agricultural Ex-
periment Station, one by the Porto Rico Experiment Station,
and one figure by the South Carolina Agricultural Experiment
Station.
LIFE HISTORY OF INSECTS
In order to apply remedial measures intelligently, it is
necessary to know something of the manner of development of
an insect; the different stages thru which it passes; the time
spent in each stage; its habits; etc. These make up its life
history."
All insects during their lifetime, pass thru four more or
less well-marked and different stages: (1) The egg; (2) the
larva or active young; (3) the pupa or the transition stage; and
(4) the adult or perfect insect, technically called the imago, and
which usually possesses wings.
In the life history of some insects, such as butterflies and
moths, beetles, and flies, the larva, called a caterpillar, grub, or
maggot, respectively, does not in the least resemble the adult
insect; and the pupa is inclosed in a rigid case incapable of
motion except for a twisting and turning of the abdomen, but
the pupa of the fly can often crawl. Such insects are said to
have a complete metamorphosis. In the life history of others,
as the true bugs and grasshoppers, the larva, commonly called
a nymph, resembles the adult insect, altho it is smaller, has no
wings and the organs of reproduction are but partly developed.
It may be active during the pupal stage and have little swellings
where the wings are to appear. Such insects are said to have
an incomplete metamorphosis.
Hairless caterpillars are often called worms altho very
different from true worms as represented by earth-worms
(" fish-worms"), tape-worms, and nematodes.
Some insects are most easily killed in the egg stage, others
in the larval, pupal or adult stages. Close study of the life
history of an insect will generally disclose its vulnerable points.
Insects may be divided into two classes, biting and suck-
ing, according to their method of taking food. The biting in-
Florida Agricultural Experiment Station
sects, represented by caterpillars, grasshoppers, and beetles,
have jaws for chewing and they eat holes in plants or consume
all of the tissue. The sucking insects, represented by true
bugs, moths, butterflies, flies, and thrips, have mouth-parts
which form a piercing and sucking tube while the crop acts as
a pump. These insects use only the juices of the plants for food.
INDIRECT METHODS OF COMBATING INSECTS
Ravages of insects may be controlled by either direct or
indirect methods. Direct methods include the application of
insecticides or poison baits, hand-picking and collecting in pans,
traps, or special appliances. Indirect methods refer to cultural
methods; the use of trap crops, and the protection of the
enemies of insects. As an ounce of prevention is worth a
pound of cure, a few precautionary measures taken at the right
time may forestall outbreaks of insects which it would be more
expensive to fight by direct measures.
CULTURAL METHODS
Frequently a slight change in the method of growing a
crop will forestall a serious outbreak of some insect. These
modifications of farm practice may be beneficial to the soil
aside from giving protection against insects. For instance, in
many cases, as soon as a crop is harvested the land should be
plowed for the next crop, turning under the refuse in which
insects may propagate. This will conserve the moisture, add
humus to the soil, and stop the breeding of insect pests by
burying many of them. Many insects spend the quiescent or
pupal stage in the ground. If the land is plowed and har-
rowed, most of these insects will be either crushed outright,
left on the surface where birds or other enemies can pick them
up, have their pupal cells broken, causing the insect to die from
exposure to the elements, or they will be buried so deeply that
emergence is impossible.
A cover crop should be grown on truck land during the
summer; a crop being chosen which will not harbor the same
pests that infested the crop which has gone before, and, espe-
cially, different from those of the crop which is to follow. If
the land is permitted to grow grass and weeds during the sum-
mer it gets thoroly stocked with cutworms, white grubs, and a
great variety of other undesirable inhabitants.
Rotation of crops is as important from the standpoint of
insect control as from that of the maintenance of soil fertility.
Bulletin 151, Truck and Garden Insects
If crop after crop of the same thing is planted, there is likely
to be such a serious accumulation in the soil of insect pests of
that crop as to make its culture unprofitable. Furthermore,
closely related plants should not follow each other in the rota-
tion, as their insect enemies are similar.
DESTROY WORMY FRUIT
Wormy fruit should be disposed of, usually by being
picked with the marketable fruit and sorted out at the packing
house. Too often it is left in the field. However, if the pick-
ing season is brief and the insect is of a species that is not
likely to crawl out, the fruit may be left in the field to be de-
stroyed with the remainder of the refuse at the end of the
season.
TRAP CROPS
The best way to get rid of an insect on a valuable crop
may be to furnish him with something he likes better; some
cheap, easily grown crop which he prefers to the more valu-
able one. Such a crop is called a trap crop. The trap crop
should be destroyed as soon as heavily infested and before there
is time for the insect to start a new generation. If allowed to
stand too long, it may increase rather than decrease the num-
ber of noxious insects on the more valuable crop.
NATURAL ENEMIES
Every insect has its own specific enemies. Some animals
prey on insects in general and others on certain families of in-
sects. Such animals are often of great value in preventing
insect outbreaks and it is very important that they be protected
by the trucker. Many enemies of insects are other insects.
With the exception of wasps, these are not generally persecuted
by man. With mammals, however, it is different. Insects make
up a large percentage of the food of toads, lizards, and the
smaller varieties of snakes. These animals should be protected.
Skunks, too, feed largely on insects and should be protected,
even at the cost of making chicken houses proof against them.
Most birds are valuable allies of man in the fight against
insects and weeds; and as such merit more rigid protection than
is now afforded them. To destroy them indiscriminately for the
small morsel of meat they afford or for mere sport is unwise.
They are worth more as destroyers of insects. An increase in
the number of insectivorous birds would decrease the loss from
insect depredations.
Florida Agricultural Experiment Station
DIRECT METHODS OF COMBATING INSECTS
Among the direct methods of controlling insects, the primi-
tive one of collecting them by hand may be found the most satis-
factory in some cases. This is especially true in dealing with
the larger insects, which are readily seen or located by the
conspicuous damage done.
One of the best accessories for hand-collecting is a pan con-
taining a little water covered with a film of kerosene, or the
kerosene alone may be used. The insects are knocked into this
pan, and are finally killed by the kerosene, even tho they may
crawl out of the pan.
POISONOUS INSECTICIDES
With reference to the use of insecticides, insects may be
divided, as stated previously, into two classes; those that have
biting mouth-parts and chew their food and those that have
sucking mouth-parts and get their nourishment by sucking the
juices of their food plants. The class of insects to be dealt
with may be determined readily by examining either the mouth-
parts of the insects or the nature of the damage to the plant.
If the insect has jaws or the plant has pieces chewed out of it,
the insect belongs to the biting class. If the mouth-parts are
in the nature of a lance or sucking tube, or the plant curls,
wilts, or turns yellow or is dwarfed, without any external in-
jury other than a small puncture, the insect belongs to the suck-
ing class. It is necessary, however, to examine the roots, as
well as the parts of the plant above ground, as injury to the
roots will cause the plants to wither and turn yellow, even in
the absence of destructive insects.
Biting insects can be poisoned by covering the plant with
a stomach poison, some substance which, when eaten with the
plant tissue, will poison them. Sucking insects must be killed
by a contact insecticide, some substance that kills the insect by
being drawn into its spiracles. Insects do not possess lungs
and do not breath thru their mouths as do the higher animals,
but thru openings in their sides called spiracles.
ARSENICALS.-The stomach poisons in most common use are
compounds of arsenic. The three commonly used are paris green,
lead arsenate, and zinc arsenite. The last two come in the
form of either a powder or a paste and can be applied as either
a dust or a liquid.
Paris Green.-The oldest of the arsenicals, paris green, is
not used as extensively as formerly on truck crops, chiefly be-
Bulletin 151, Truck and Garden Insects
cause of its tendency to burn tender foliage. One can diminish
this danger by adding to the solution hydrated lime or the milk
obtained from slaking quick lime. A good formula is:
Paris green ................................. .. .... ......... 5 ounces
Lim e ............................... ..................... ..... 2 pounds
W ater .................... .......................... ............50 gallons
Lead Arsenate.-The poison now commonly used on truck
crops is lead arsenate. It is not as likely to burn as paris
green. One pound of the powder or 2 of the paste to 50 gal-
lons of water, makes a liquid about as strong as it is ordinarily
necessary to use. On very tender plants, such as beans, it is
well to add 2 pounds of lime as in the paris green mixture.
The powdered form of lead arsenate is cheaper than the paste
and but little more troublesome to make up. By joining with
other truckers and ordering in 100 pound drums, lead arsenate
can be had for about twenty cents a pound and can be used
either as a dust or in water.
Zinc Arsenite.-This is a new but promising insecticide.
It is less poisonous to stock or man than lead arsenate and
should be sold at about the same price, making it somewhat
cheaper as a less quantity is required. It is much lighter than
lead arsenate and works better as a dust. It has the disad-
vantage that it is not yet as generally on the market as the
other arsenicals and consequently is harder to get. Like lead
arsenate, it comes in both powder and paste forms.
Calcium Arsenite.-A still newer arsenical is calcium ar-
senite. It is the cheapest of all the arsenicals and does not
scorch ordinary truck crops. It is lighter than zinc arsenite.
LIQUID SPRAYS.-These are generally more efficient than the
dusts in their results as they cover the plant more thoroly and
require less of the poison to the acre, but are usually more ex-
pensive to apply on account of the labor involved, particularly
if water is not handy.
Mixing.-In making up any of these substances in sprays,
the proper amount should be mixed first in a few gallons of
water until all lumps have disappeared and then be added to
the bulk of the water. It is better to put some substance into
the solution that will act as a spreader so that the spray will
wet the surface of the plants more evenly, and also stick better.
In spraying glossy plants like cabbage, this is imperative. For
a list of these spreaders and directions for making them see
under cabbage butterflies, page 141.
Florida Agricultural Experiment Station
DUSTS.-The use of dusts in place of liquid sprays is be-
coming common. They are especially adapted to cheap farm
crops but are used on the truck farm to check an insect out-
break in its early stages. They are best if applied in the early
morning when the plants are wet with dew.
In a small garden the dust may be applied by shaking
from a perforated tin can or from a bag made of muslin, but
on a truck farm a dusting machine should be used. There are
many of these machines on the market, ranging from a small
bellows-like affair to a large power duster driven by a gasoline
engine. Those which can be carried and operated by a man
while walking thru the field will be found quite satisfactory for
truck farms. The prices of these range from ten to fifteen
dollars. Undiluted arsenicals can be used in the machines, but
it is usually more economical to dilute them with at least equal
parts of some carrier such as hydrated lime, air-slacked lime,
land-plaster, or flour.
CONTACT INSECTICIDES
TOBACCO.-This is one of the most common of the contact
insecticides used against small and delicate insects. It is also
one of the safest for in excessive dosages only is there any
danger of scorching the plants. For directions for its prepara-
tion and use see melon aphis under watermelons, page 199.
KEROSENE EMULSION.-For large insects, as well as small
ones, kerosene emulsion is a standard remedy, but unless made
and applied carefully it is likely to scorch tender foliage. The
stock solution is:
H ard soap .......................... ............................ 1/ pound
Hot water (soft) ..... ................---- .....1. gallon
Kerosene (coal oil) ..................................... 2 gallons
Shave the half pound of laundry soap into the gallon of
soft water, stirring it until the soap is dissolved. When all is
in solution, remove the liquid to a safe distance from the fire
and add the kerosene. Emulsify the solution quickly with a
bucket pump by turning the nozzle back into the bucket and
forcing the solution thru the pump several times until a smooth
creamy emulsion is formed. If this is done properly no free
oil will collect on the surface when the solution cools.
For spraying dormant trees and shrubs use 1 part of the
solution to from 5 to 7 parts of water. On ordinary growing
plants dilute with 10 to 15 parts of water, depending on the
insect to be killed. The weakest solution given will kill plant
lice.
Bulletin 151, Truck and Garden Insects
SOAP.-Any strong alkaline laundry soap is a good insecti-
cide. (Before the recent advance in the price of potash, whale-
oil or fish-oil soap was the cheapest.) The higher priced, more
nearly neutral toilet soaps are not as good because the free
alkali of the cheaper soaps is needed to kill the insects. One
pound of soap to 8 gallons of soft water will kill most small,
soft-bodied insects. If more soap is added, the killing power
of the solution is increased but little, and if more than 8 pounds
to 50 gallons of water is used the killing power is actually de-
creased. If less than 6 pounds to 50 gallons is used, the killing
power is also decreased. If the water is hard more soap will be
needed as some of it is used in softening the water.
PYRETHRUM OR PERSIAN INSECT POWDER.-Pyrethrum is
much used against household insects. It is too expensive for
general use in garden and truck farms. It rapidly loses its
strength when exposed to the air.
BORDEAUX.-Bordeaux mixture, the common fungicide, is
used to repel such insects as flea-beetles. But its chief interest
with regard to insect control, lies in the fact that it can be com-
bined with most arsenicals. This makes a spray that will kill
both fungi and biting insects. Tobacco can also be mixed with
bordeaux to kill sucking insects. In mixing these insecticides
with bordeaux, let the bordeaux solution take the place of the
water called for in the formula.
The following directions for preparing bordeaux mixture
are given by the plant pathologist of the Station:
Bordeaux mixture is made from bluestone (copper sulphate), rock lime,
and water. If much spraying is to be done, make stock solutions of the
bluestone and lime; from these, bordeaux mixture of any strength can be
made.
To make these stock solutions, take a barrel which holds 50 gallons of
water; suspend 50 pounds of bluestone in a gunny sack or cheese cloth at
the top of the water so that half of the bluestone is below water. After
it is all dissolved there will be one pound of bluestone to every gallon of
the solution. Place 50 pounds of good rock lime in another barrel and
slake it. Then add water until there are 50 gallons of the lime water.
Bordeaux mixture is used in different strengths, according to the
season of the year and the kind of plants to be sprayed. A 5-5-50 bor-
deaux mixture means a mixture containing 5 pounds of bluestone, 5 pounds
of lime, and 50 gallons of water. In all formulae of bordeaux mixture, the
first figure refers to the number of pounds of bluestone, the second figure
to the number of pounds of lime to be used, and the third to the number
of gallons of water.
To prepare the 5-5-50 mixture, two more barrels of 50 gallons capacity
each are needed. In one barrel put 40 gallons of water and 10 gallons of
the bluestone solution. In the second barrel put 40 gallons of water and
10 gallons of the lime water. Take equal parts from each of the two
barrels containing the dilute solutions and pour them simultaneously into a
spraying machine. These mixtures should be poured thru a very fine
sieve or cheese cloth to keep the larger particles from entering the ma-
Florida Agricultural Experiment Station
chine. The solution should be constantly agitated while the mixing is tak-
ing place. The lime solution should be kept stirred so that each gallon
will contain the same amount of lime.
Smaller quantities can be made by dissolving the amount of blue-
stone required in half the amount of water needed. The lime needed
should be slacked and added to the other half of the amount of water
required. The two solutions can be poured simultaneously into a third
vessel, but stir the mixture while pouring the two solutions together.
Only wooden vessels should be used as bluestone corrodes metals. Be
sure to pour the mixture thru a fine sieve or cheese cloth before putting
it into the sprayer, or the particles will clog the nozzles.
Bordeaux mixture must be used the same day that it is made, for if
left standing over night it loses its strength. The stock solutions of blue-
stone and lime can be kept indefinitely, but when they are to be used the
water which has been lost by evaporation must be replaced.
FUMIGATION
The trucker or gardener will ordinarily use this method of
killing insects only in greenhouses, cold frames and bins where
seeds or other plant products are stored.
The common fumigants are:
SODIUM CYANIDE AND AMMONIUM SULPHATE.-See page 201.
CARBON BISULPHIDE.-See weevils under corn, page 159.
PARADICHLOROBENZENE.-See weevils under corn, page 159.
HYDROCYANIC-ACID GAS.-This gas is cheaper than carbon
bisulphide for fumigating large rooms and buildings and has the
added advantage of being noninflammable. It is extremely
poisonous and great care must be exercised not to inhale it. It
is made in the following way:
Compute the cubic contents of the room; then close it
tightly and stuff all cracks with rags, or paste paper over them.
Get a large earthenware jar and pour into it 3 fluid ounces of
water for each 75 cubic feet of space. Into this water pour 1
fluid ounce of commercial sulphuric acid for each 75 cubic feet
of space. Be sure to pour the acid into the water and not the
water into the acid; otherwise you will probably break the jar
by the heat generated and may be severely burned by the sput-
tering acid. Into this diluted acid drop 1 ounce of potassium
cyanide for each 75 cubic feet of space. The jar should be so
large that it is not more than one-third full before the cyanide
is added, otherwise it is likely to boil over. After dropping
the cyanide in, leave the room promptly, shutting the door and
locking it. The gas will begin to form at once. Cyanide is
one of the most powerful poisons and should be handled with
extreme care. It is well for the operator to wear rubber gloves
if the skin has been injured on any part of his hand and the
hands should be thoroly washed before being permitted to touch
the lips.
Bulletin 151, Truck and Garden Insects
The foregoing dose is twice that of the "horticultural
dose and is about as strong as can be used in a tight room or
box without endangering the germinating power of the seed.
The horticultural dose is that used on nursery stock and is in-
tended to kill insects without injuring the plants.
Sodium cyanide may be substituted for potassium cyanide
and is much cheaper. Use less of the sodium than of the
potassium salt. To fumigate a room containing 100 cubic feet
of space, pour 2 fluid ounces of water into the jar, and into
this pour 11/2 fluid ounces of sulphuric acid. To complete the
mixture, add 1 ounce of sodium cyanide. Sodium cyanide is
sold in pieces weighing approximately one ounce. This obviates
the necessity of weighing the material.
ToBAcco.-Tobacco is used as a fumigant in greenhouses
and other closed places. Sheets of tobacco paper" manufac-
tured especially for the purpose, or tobacco stems and refuse
may be used. The material is set on fire and the fumes of nic-
otine given off in the burning kills all tender insects in the
space. Tobacco stems are moistened so that they will smoulder
and smoke but produce no flame.
NAPHTHALENE.-Naphthalene, the active ingredient of moth
balls, is fairly good as a repellant to keep insects out of stored
grains and seeds but it does not kill them.
HEAT
A temperature of from 120 to 130 degrees Fahrenheit, if
maintained for a half hour, is fatal to practically all insect life.
If a bag of seed can be placed in an oven, with a dish of water
to supply moisture, and kept at a temperature of 120 to 130
degrees F. for from 20 to 30 minutes, insects in it will be killed
and the germinating power of the seeds will remain unimpaired.
GENERAL GARDEN INSECTS AND PESTS
There is a number of insects that attack practically all
garden crops and could not well be included under only one of
them. They are treated here.
GRASSHOPPERS
These insects are particularly annoying on early fall crops.
At that time native vegetation is becoming dry and unattractive
and the grasshoppers, many of which are then in the late
nymphal or the adult stages and consume more vegetation than
the very young, flock to the farmers' crops.
Florida Agricultural Experiment Station
S There are many genera and species of grasshoppers. One
of the most common and troublesome is the red-legged grass-
hopper. This is one of the smaller kinds but makes up in
numbers what it lacks in size. On flatwoods and muck lands
the lubberly locust is often troublesome. This is the largest
grasshopper in Florida. The young are black. There are two
color-forms of the adults. Some are of a striking red color
and others are almost as black as the larvae. These grasshop-
pers have very short wings and are incapable of flight.
Grasshoppers lay their eggs in the ground in waste places
at a depth of 1 or 2 inches. Cultivation will destroy the eggs
when they are laid in cultivated land; consequently it is in
small fields surrounded by waste land that grasshoppers are
most troublesome. As the amount of land under cultivation in
a neighborhood increases, these insects become less as a pest.
Control.-Birds, including domestic fowls, especially tur-
keys, are very fond of grasshoppers. The general farmer
should keep a flock of turkeys, for their insecticidal value if for
no other reason. They would, of course, be out of place on a
truck farm or town lot. The lubberly locust is, however, dis-
tasteful to all birds and will not be eaten by them.
The cheapest and most effective method of dealing with
grasshoppers is by means of poisoned baits, of which the so-
called Kansas formula is the best. It has proven very sat-
isfactory wherever tried. It is
Bran ........................................ ---.---- 20 pounds
Paris green or sodium arsenite................ 1 pound
W ater _....-.....--.....--....-.. ........--- ----- 2/2 gallons
Lemons, oranges, or cantaloupes................ 3 or 4
Syrup .......................-- -----........-- 2 quarts
The paris green and bran should be thoroly mixed (dry).
Lead arsenate should not be used. It does not work as well.
The lemons should be thoroly grated or chopped very fine, rind,
pulp, and juice, and added to the water. Moisten the bran
with the water until the whole is damp, not sloppy, so that when
sown broadcast over the land it will fall in small flakes. Last
of all add the syrup and thoroly knead it into the bran. This
should be sown in the early morning, about sunrise or before.
Grasshoppers do not eat at night, and consequently have a
good appetite in the early morning, and the bait should be on
hand for their breakfast.
If sown in small flakes over the field there will be no like-
lihood of chickens or other domestic animals picking it up, nor
Bulletin 151, Truck and Garden Insects
will wild birds be endangered. Ordinarily there will be no
danger to chickens or other fowls eating the dead grasshoppers
as the fowls will not get enough arsenic in this way to harm them.
MOLE-CRICKETS
These are flat like other crickets. Their front legs are
greatly enlarged and fitted for burrowing (fig. 56). They live
deep in the ground during the daytime,
coming out at night to feed. They are
very destructive to vegetation, particularly
in gardens and seed beds. They make,
Just beneath the surface of the ground,
runways resembling those of moles but
very much smaller.
There are at least two native species
of mole-crickets that are somewhat de-
structive in truck patches, especially in
low ground where there is considerable
vegetable mold. In addition, the West
Indian mole-crick-
et or change"
(fig. 57) is becom-
ing very trouble-
some in some sec-
FIG. 56.-Native mole- tions of the State.
cricket. Natural size. Contrl.-Sul-
(Original.) Control.-Sul-
phur placed in the
seed drill is said to act as a deterrent.
Mole crickets may be kept out of seed
beds by a gauze floor. At the time the
seed bed is made, dig out the earth to
the depth of a foot or so and place in
the bottom a layer of galvanized or cop-
per wire mosquito netting. It should
come up at the sides and project a couple
of inches above the ground.
Plants set out in the field may be
FIG. 57.--"C h a n g a" or
West Indian mole-
cricket. Natural size.
(Porto Rico Exp. Sta.)
protected by banding them. For this purpose, melt off the tops
and bottoms of tin cans and place the cylinder over each plant,
sinking it into the earth to some depth. Instead of the tin
cans, tarred paper may be used.
Mole-crickets may be poisoned by a mixture of cottonseed
meal, paris green and syrup. Mix thoroly a pound of paris
___1
Florida Agricultural Experiment Station
green with 25 or 30 pounds of cottonseed meal, and then
moisten the whole with cheap syrup.
Like other insects which live in the ground, mole-crickets
may be poisoned by carbon bisulphide. Sink into the infested
garden several holes to the square yard. These can be made
with a cane, if the soil is a bit moist, and should go down to a
depth of one foot. Pour into each hole an ounce of the liquid,
and quickly cover the hole. Care must be taken to keep the
liquid away from the plants or they also will be killed; also
keep the liquid away from fire or lights as it is very inflam-
mable.
To reduce the number of mole-crickets in badly infested
ground, plow deeply several times in the spring, from March to
June, when they are breeding most actively. Allow chickens,
and especially turkeys, to follow the plow for they are very
fond of these insects. Pasture hogs on the field when possible.
When mole-crickets are flying during March or April (they do
not fly much at other seasons) great numbers can be caught
in light traps. Suspend a lantern in the field and place under
it a pan of water on the surface of which there is a thin layer
of kerosene.
The best bait for mole-crickets is that developed by the
Porto Rico Station. It consists of:
Low grade flour............... .............-- 50 pounds
Paris green............... ......... .. 1 to 11/2 pounds
Mix thoroly and scatter broadcast at the rate of 250 to 300
pounds to the acre. In a cabbage or lettuce patch it may be
placed in a shallow trench around the base of the plant to be
protected. Use a heaping teaspoonful to each plant. This bait
is very effective as a means of control.
MOLES
Moles are a nuisance in lawns and gardens because of the
extensive tunnels they make beneath the surface of the soil.
In making these tunnels they break off the roots of the plants
and cause the soil over the tunnels to dry out. Contrary to
common opinion, they do not eat vegetation but are purely
insectivorous in their diet. They are fond of "white grubs"
which are the larvae of May-beetles or June-bugs. These white
grubs are most abundant on land that has been allowed to grow
up in grass during the summer. The first step in fighting
moles is to get rid of the white grubs. This can be done by
raising some cover crop such as cowpeas, velvet beans or pea-
Bulletin 151, Truck and Garden Insects
nuts on the land to keep down the grass during the summer,
and also by turning pigs in on the land for a few weeks before
the garden is plowed. (See white grubs under potatoes, page 178,
for further suggestions.) Altho, by eating the white grubs,
moles perform a good service to the grower, like some other
troubles, the remedy is often worse than the disease.
Control.-Moles may be discouraged from burrowing in
the garden by tramping the soil solidly into their runways or
crowding a brick or a stone into it where it enters the garden
from the outside, making sure of course, that the mole is not
in the garden when this is done. The presence of the mole is
best detected in the early morning by the ridges of fresh dirt
or the movement of the soil as he forces his way thru it. In
the latter case the mole can at once be dug out and either killed
or, better, carried off to some pasture or waste land where his
activities will be beneficial rather than harmful.
Moles make two types of tunnels. One is the feeding tun-
nel which is but a few inches below the surface of the ground.
The other is larger and located much deeper, a foot or more.
This is the main highway for the moles in going from one end
of their range to the other. Moles may be trapped by uncov-
ering this main roadway and placing in the breach a mole trap,
several of which are on the market.
The prevalent idea that moles eat the roots of plants arises
from the fact that the runways of moles are commonly used
by field mice which do the damage. Stopping up the runways
will discourage the mice as well as the moles. In the kitchen
garden both moles and mice may often be drowned out by turn-
ing the garden hose into the runway. The mice may be pois-
oned by putting in the runways some corn that has been soaked
in arsenic, paris green or strychnine. The moles will not eat
this corn.
SALAMANDER
The so called salamander of Florida is a ground squirrel
much more nearly related to the pocket gopher of the west
than to the true salamander which is a frog-like animal with
a tail. If they invade the garden they may be poisoned by
the bait given for mice.
GOPHER
Like the salamander," this animal is misnamed. It is
not at all related to the true gophers, but is a land turtle. Like
the last, it makes tunnels in the fields but they are much larger
and the animals do not throw up piles of dirt in more or less
Florida Agricultural Experiment Station
straight rows as do the salamanders." Probably the best way
to get ride of these turtles is to put into the holes they make, a
wad of cotton which has been soaked in carbon bisulphide.
ANTS
One of the nuisances with which the gardeners and truckers
have to contend is ants. The amount of damage they will do
depends to a large extent on the species. Following are men-
tioned some of the ways in which they are annoying in a garden.
They eat off growing plants such as cabbage. Most species
feed to a limited extent only on growing vegetables, but many
species seem to object to the presence of vegetation about their
nests. This is particularly true of the large yellow agricul-
tural ants which will keep a space many feet in diameter about
their nests absolutely free from vegetation. The leaf-cutting
ants which are found in the southern part of the State, cut off
and remove to their nests a large number of leaves. They do
not use these directly for food, but to grow a kind of fungus
of which they are particularly fond. They were the first mush-
room growers. They are particularly annoying to citrus trees
in the tropics where they abound.
One of the most annoying habits of ants is that of carry-
ing away seeds from seed beds. They are particularly fond of
lettuce and romaine seed. They use the seeds for food and will
begin to carry them to their nests as soon as planted and will
continue their pernicious activities all thru the germination
period and until the young seedlings have used up all of the
material in the seeds. Ants often cover up plants by building
mounds over them.
Ants are very fond of the honeydew given off by aphids,
some jassids, mealy bugs and other scale insects. For the sake
of this substance many kinds will tend those insects, sometimes
driving away their enemies and more commonly carrying those
pests from one plant to another. (See garden aphid under
cabbage plant-lice, page 144.)
Ants in the truck patch and garden, especially those that
sting, are somewhat of an annoyance to workers.
Control.-Ants are best destroyed in their nests. For this
purpose carbon bisulphide can be used but potassium or sodium
cyanide is cheaper and more efficient. Dissolve the cyanide in
water, an ounce to each quart of water. With a cane or sharp
stick punch a hole to the depth of a foot or more in the center
of the hill and pour into it a few ounces of the solution. The
Bulletin 151, Truck and Garden Insects
dosage to be given as well as the depth of the hole will depend
upon the size and depth of the nest. As soon as the liquid has
soaked away, cover up the hole with dirt and tramp it solid.
The gas given off will penetrate the galleries of the nest and
kill most of the ants and their young. It is best to do this in
the early morning when most of the ants are at home." All
of the nests within 50 or 60 feet of the seed bed should be
treated. As recorded under the head of fumigation, cyanide is
one of the most powerful poisons known, either when inhaled
or swallowed. It should also be kept out of open sores. Some
ants will probably escape the first treatment. These will, how-
ever, lose all interest in the seed bed and will go slowly about,
cleaning the dead ants out the nest. Their slow and languid
motions are in sharp contrast to their feverish activity of the
previous day. The survivors will probably, in the course of a
few days, start small new nests in the vicinity. These in turn
may be treated.
ROOT-KNOT (Heterodera radicicola)
This is a disease characterized by knot-like swellings on
the roots. Severely infected plants fail to make proper growth
and often turn yellow and die prematurely.
The cause is a minute round-worm or nematode which bores
into the roots to feed. It gives off a poison which causes the
plant to make the swelling. It affects nearly all garden and
truck crops, except corn, to a varying degree. The worms are
not very active during the winter, but during the warmer
weather from April to October they often make it impossible
to grow a profitable crop of certain plants on the infested land.
Newly-cleared land is usually free from these worms, but most
sandy soils of Florida, when cleared and cultivated for a num-
ber of years, become infested.
Control*.-The usual way to free infested land is to raise
only non-susceptible crops on it for three years and thus starve
out the worms. Among such immune or partly immune plants,
are, most of the true grasses, including crab-grass and Bermuda,
most varieties of corn and wheat, rye, and some varieties of
oats; velvet beans, and beggarweed, Iron and. Brabham cow-
peas are usually resistant. Onions, parsnips, strawberries and
turnips are but slightly affected. While growing any of these
crops to free the land of nematodes it is important that weeds
should not be allowed to grow there as the nematodes are
*See page 201, Other Means of Controlling Root-Knot.
Florida Agricultural Experiment Station
abundant on many of them. This is especially true of some
species of Amaranth or careless weed."
The following plants commonly grown in Florida are sub-
ject to infestation.
first- in the list:
1. Okra
2. Tomatoes
3. Eggplant
4. Cucumbers
5. Cantaloupes
6. Amaranth
(careless weed)
7. Celery
8. Tobacco
9. Peas
10. Peaches
11. Figs
12. Irish Potatoes
13. Watermelons
14. Beets
Those most liable to severe attack come
Dasheens
Peppers
Squash
Lettuce
Beans
Rape
Papaya
Carrot
Pineapples
Sunflowers
Bananas
Cotton
Radishes
Sweet Potatoes
Asparagus
Cabbage
Cauliflower
Collards
Soy Beans
Mustard
Pecans
Japanese Persimmon
Violets
Old World Grapes
Sugar Cane
Peanuts
Catalpa
Quince
Kudzu
On land which has been heavily infested it is impossible to
grow profitably the plants at the head of this list. They may
grow well at first but soon become stunted and fail to bear well.
The Station has developed a promising method of treating
seed beds to exterminate the worms or at least greatly reduce
their numbers. The material used is a mixture of calcium cyan-
amide and other substances sold under the trade name of
"Cyanamid." The method is described in detail in Bulletin 136
of this Station, which will be sent free upon request.
OTHER GENERAL PESTS
The following named pests attack a large number of veg-
etables and could have been treated appropriately under this
general heading. They are: Fall army worm or grass worm
(see under corn, page 155) ; red spiders (see under peas, page
175); garden aphid (see under cabbage, page 144); and cut-
worms (see under cabbage, page 137).
BEANS
BEAN LEAF-HOPPER (Empoasca mali)*
Several species of jassids severely attack snap beans, espe-
cially those planted early in the fall. Their ravages are often
so severe as to discourage the planting of beans at that season.
Jassids obtain their food by sucking the juices of plants.
If the insects attack in sufficient numbers the plants will be-
come stunted in growth, fail to bear well, turn yellow and
finally die.
*See alsD page 202, The Three-cornered Hcpper.
Bulletin 151, Truck and Garden Insects
Several species are concerned in this injury. The most
abundant is Empoasca mali or bean leaf-hopper. This is also
called the apple leaf-hopper, because it was first noticed on
apples which it damages severely. It is a light green insect,
V/8 of an inch long. Under a lens the eyes of the living insect
are white but they quickly turn brown after death. The bug
lives on a variety of plants but is partial to cowpeas and beans.
There are many generations a year.
Control.-These insects can be killed by a strong tobacco
extract. A successful one is:
Black leaf 40................... .... .......................2/5 pint
Soap .......................... ... ....................... 5 pounds
W ater ......................................................... 50 gallons
Kerosene emulsion will also kill them but there is more
danger of burning the delicate plants.
Spraying for this pest is expensive and not altogether sat-
isfactory because the plants are quickly reinfested from sur-
rounding vegetation. Some relief may be obtained by destroy-
ing grass and weeds about the edges of the field. Beans should
not be planted too near a field of cowpeas. In a small patch
the leaf-hopper can be caught in an ordinary insect net, made
of fine-meshed cloth, such as muslin. The net should be fre-
quently dipped in kerosene to destroy the insects caught.
If one has a large acreage it will pay to use a machine for
catching these pests. Such machines are constructed on the
plan of the well known hopperdozers for catching grasshoppers.
They consist of a vertically placed framework mounted on
runners for drawing over the field. The bottom edge of the
frame is placed at a height sufficient to strike the tops of the
plants as it is drawn among them, causing the insects to jump.
This frame is covered with either a smooth polished metal or a
canvas smeared with a sticky substance in which the insects
are caught. If the hoppers strike the smooth metal they will
slide into a trough of kerosene or into a box-like trap fastened
to the lower edge of the metal. If the canvas is used, smear it
with tree-tanglefoot diluted with castor oil to the proportion of
1/4 pint to each pound of tanglefoot. A cheap commercial grade
of castor oil is used and the coating will need to be renewed for
every 5 acres. These hopperdozers are illustrated in Farmers'
Bulletin 737, United States Department of Agriculture, from
which the foregoing recipe was taken.*
*See also page 202, Control of Bean Leaf-hopper.
Florida Agricultural Experiment Station
BEAN LEAF-ROLLER (Eudamus proteus)
Another insect which is very troublesome to the early fall-
planted crop is a caterpillar which rolls up the edges of the
leaves after cutting slits in them. From these shelters the
caterpillars range over the leaves which are often so badly
eaten that no pods can be formed.
The caterpillar (fig. 58), which grows to an inch in length,
is a light greenish-yellow, velvety insect. The brownish-yellow
head is attached by a neck which is much narrower than usual
in caterpillars so that there is a marked constriction between
the head and thorax.
In the summer the larva will complete its growth in 14
days, but in October and November, 30 or more days are re-
quired. The larva then forms the pupa on the plants and in 6
FIG. 58.-Bean leaf-roller: Larva. Much enlarged.
(Original.)
days the bluish butterfly emerges. The insect belongs to the
group of butterflies known as skippers," doubtless because of
their habit of darting quickly from plant to plant in search of
nectar or a place for an egg. The eggs are deposited on beans
and other legumes, especially beggarweed, and hatch in 4 days
in summer. This group of butterflies when at rest, hold their
wings at an angle of about 45 degrees instead of horizontal or
perpendicular as do other butterflies. This specie (fig. 55)
may be distinguished from other skippers by its larger size, 2
inches across the outstretched wings, and by the prolongations
(" tails ") of the hind wings.
The insects are scarce in the spring and early summer so
that early beans are not troubled. But by the first of Septem-
ber the butterflies are abundant and beans become heavily in-
fested.
Control.-The insect can readily be killed by spraying with
lead arsenate. However, beans are easily injured by arsenicals
so not over 12 ounces of the powdered, or a pound and a half
of the paste, form of lead arsenate should be used to 50 gallons
of water, and to this should be added, before using, a pound of
Bulletin 151, Truck and Garden Insects
hydrated lime or the milk obtained from slacking 2 pounds of
quick lime in water. If jassids are also present, add tobacco
to the solution.
BEAN-WEEVIL (Bruchus obtectus)
There are two or three species of weevils that infest beans.
The most common is Bruchus obtectus (fig. 59). The others
are more common on cowpeas and will be treated under that
heading. The ravages of this insect on dried beans are very
conspicuous; in fact, if not checked, it will entirely destroy
seed beans. They also damage snap beans. The infested pods
show wart-like swellings where the female punctures them to
lay eggs in the cavity of the pod. She gnaws out a narrow slit
and then inserts her ovipositor in the hole and lays the egg.
These speckled" pods should not be
confused with those having spots
caused by the fungus, Colletotrichum.
Those spots caused by the fungus are
sunken instead of elevated and attain
a much larger size. The egg hatches
6 W in from 1 to 3 weeks, according to the
FIG. 59.B e Bea wee v 11 prevailing temperature, into a small,
(Br u c h u s obtectus): a, worm-like larva. This requires from
Adult beetle, much en
large; b, infested bean. 11 days to 6 weeks to become full
(From U. S. Bur. of Ent.)
grown and then changes into the pupa.
From 5 to 18 days later the adult emerges. This is an ashy-
black beetle about a tenth'of an inch long with hard wing-cases
and' somewhat flattened body.
Nothing can be done to protect the beans in the field from
the ravages of this insect. The best method of control is to
plant clean seed in a field that has not recently produced a crop
of cowpeas or beans. Breeding in dried beans can be prevented
by keeping the beans in cold storage (32 to 34 degrees F.) for
two months or more, or they may be fumigated as recommended
for stored seeds.
LESSER CORN STALK-BORER (Elasmopalpus lignosellus Zell.)
This insect is injurious to corn in the states farther north;
in Florida it does more damage to cowpeas and beans, altho it
is injurious to corn. Next to the bean-jassid it is the most injuri-
ous insect on fall-planted beans. It often destroys almost the
entire stand if control measures are not adopted. The insect
.is a bluish-green caterpillar (fig. 60, d) which bores into the
Florida Agricultural Experiment Station
stem at the surface of the ground and tunnels up and down in
it, causing the young plant to wilt and die quickly. If the
cowpea-plant gets a good start before it is attacked it is not
easily killed and may produce some pods, so that the damage
is not as noticeable, but a bean is usually killed outright. The
full-grown caterpillar is about a half-inch long. It is quite
smooth; i. e., it is not noticeably hairy. There is a large brown
spot on the back of each segment (joint). The head is brown
and hard and the first joint of the thorax is black. The adult
d -bb
FIG. 60.-Lesser corn stalk-borer (Elasmopalpus lignosellus):
a, Male moth; b, wing of female moth; c, moth, showing the
resting position of the wings; d, caterpillar; f, pupa. About
three times natural size. (From U. S. Bur. of Ent.)
is a small, brownish moth with cream-colored markings (fig.
60, a). It belongs to the same family as Crambus (see root
webworms under corn, page 156) and rolls its wings about its
abdomen in the same manner (fig. 60, c.)
SThe female lays her eggs on the stem near the surface of
the soil and the caterpillar feeds on the surface of the roots
until about half-grown, when it bores into the stem.
Control.-The. caterpillars, working inside of the stems, are
safe from any poison that could be applied to the crop. The
young on the roots are also safe. The only means of prevent-
ing their spread thru a field is to pull up and destroy all in-
fested plants. Rotation of crops should be practiced. Beans
should not be planted on land that has just grown beans, pea-
nuts, cowpeas, turnips or corn, as they are all host plants.
BEAN LEAF-BEETLE (Ceratoma trifurcata, Forst)
This beetle is not as common in Florida as in the other
Gulf states. The eggs are laid in clusters of about a dozen
Bulletin 151, Truck and Garden Insects
just below the surface of the ground. The adult beetle feeds on
the leaves of beans and cowpeas. The larva feeds on the roots
of the same plants, particularly the nodules of the nitrogen-
fixing bacteria. For this reason the insects are a serious pest
when occurring in large numbers.
If these beetles become numerous in a field of beans, the
plants should be sprayed with a solution of bordeaux mixture
containing a pound of lead arsenate to 50 gallons of the bor-
deaux. (See introduction for directions for making bordeaux
mixture.)
OTHER BEAN PESTS
Other insect-pests attacking beans are: Root-knot nema-
tode (see under general garden pests, page 128) ; cutworms (see
under cabbage, page 137) ; corn ear-worm (see under corn, page
151), sometimes mines the pods; cabbage looper (see under
cabbage, page 140), sometimes eats the leaves; cowpea pod-
weevil (see under cowpeas, page 160) ; grasshoppers (see under
general garden pests, page 122) are troublesome in the fall;
pumpkin bug (see under cowpeas, page 161) and other plant-
bugs (see under potatoes, page 177) are among the most trouble-
some enemies of the bean grower; garden aphid (see under
cabbage, page 144); wireworms (see under corn, page 153);
flea-beetles (see under beets, page 136) ; and striped cucumber-
beetle (see under cucumbers, page 166).
LIMA BEANS
GALL-WORM (Monoptiloba sp.)
In addition to the pests of other beans, lima beans are
attacked by a caterpillar that bores into the stems. The plant
thus attacked forms a large swelling or gall about the larva.
In this gall the larva lives, feeding on the tissue until its growth
is complete. The adult insect emerges as a small moth, and
lays eggs on the stems of the plant. These galls are very com-
mon on lima beans in Florida. There seems to be no practical
means of preventing this injury. If the beans are well fertil-
ized and cultivated they will bear well in spite of this insect.
BEETS
BLISTER-BEETLES
These long, slender beetles feed on a variety of truck
plants, including beets, tomatoes and potatoes. In the Northern
States these insects are known as old-fashioned potato bugs "
Bulletin 151, Truck and Garden Insects
just below the surface of the ground. The adult beetle feeds on
the leaves of beans and cowpeas. The larva feeds on the roots
of the same plants, particularly the nodules of the nitrogen-
fixing bacteria. For this reason the insects are a serious pest
when occurring in large numbers.
If these beetles become numerous in a field of beans, the
plants should be sprayed with a solution of bordeaux mixture
containing a pound of lead arsenate to 50 gallons of the bor-
deaux. (See introduction for directions for making bordeaux
mixture.)
OTHER BEAN PESTS
Other insect-pests attacking beans are: Root-knot nema-
tode (see under general garden pests, page 128) ; cutworms (see
under cabbage, page 137) ; corn ear-worm (see under corn, page
151), sometimes mines the pods; cabbage looper (see under
cabbage, page 140), sometimes eats the leaves; cowpea pod-
weevil (see under cowpeas, page 160) ; grasshoppers (see under
general garden pests, page 122) are troublesome in the fall;
pumpkin bug (see under cowpeas, page 161) and other plant-
bugs (see under potatoes, page 177) are among the most trouble-
some enemies of the bean grower; garden aphid (see under
cabbage, page 144); wireworms (see under corn, page 153);
flea-beetles (see under beets, page 136) ; and striped cucumber-
beetle (see under cucumbers, page 166).
LIMA BEANS
GALL-WORM (Monoptiloba sp.)
In addition to the pests of other beans, lima beans are
attacked by a caterpillar that bores into the stems. The plant
thus attacked forms a large swelling or gall about the larva.
In this gall the larva lives, feeding on the tissue until its growth
is complete. The adult insect emerges as a small moth, and
lays eggs on the stems of the plant. These galls are very com-
mon on lima beans in Florida. There seems to be no practical
means of preventing this injury. If the beans are well fertil-
ized and cultivated they will bear well in spite of this insect.
BEETS
BLISTER-BEETLES
These long, slender beetles feed on a variety of truck
plants, including beets, tomatoes and potatoes. In the Northern
States these insects are known as old-fashioned potato bugs "
Florida Agricultural Experiment Station
to distinguish them from the more recently introduced Colo-
rado potato-beetles." They are known in parts of Florida as
"Yankee bugs," perhaps from the bluish color of certain species.
The adult beetle crushed against the skin causes a blister, hence
the name blister-beetle." It is also called Spanish fly," cer-
tain species being the source of the drug of that name.
Eight species of blister-beetles are more or less trouble-
some to vegetation in Florida. The most common one is the
gray blister-beetle (Epicauta heterodera) which has no stripes.
The striped blister-beetle (E. vittata) (fig. 61) is frequently
seen.
The work of all the species is about the same except that
each shows a preference for different plants. They strip all
the softer parts of the leaves, leaving only the mid-
ribs. The beetles usually feed in colonies, some-
times so large that they quickly strip and ruin a
patch or an entire field.
If the colony is small the quickest way to
exterminate it is to collect the beetles in a pan of
\ kerosene. They are quick to take alarm and the
F GG 61.- collector must work rapidly. If the colony is large
blister- the plants should be sprayed with lead arsenate.
Natural The larvae feed on the eggs of grasshoppers and
size. (From
U. s. Bur. are beneficial to agriculture. For this reason it
of Ent.)
is better, wherever possible, to drive the beetles
from the field rather than to poison them. To do this, use
a bundle of twigs with which to whip the plants and work
with the wind, driving the beetles quite a distance from the
field to prevent their quick return. It may be necessary to
repeat this driving frequently.
BEET LEAF-MINER (Pegomyia vicina)
This insect belongs to a large class made up of small pests
which often escape the notice of the trucker because of the
small size of the insect and the wound inflicted, while the un-
thrifty condition of the injured plants is laid to a lack of fer-
tilizer or water. Collectively they inflict severe damage.
This maggot-like larva of a two-winged fly frequently
burrows in the tissue of beet leaves. If they become numerous
they will materially check the growth of the plants.
In its protected position, the grub cannot be reached by
any insecticide, but the grower can check an outbreak by de-
stroying all infested leaves. This at least should be done when
Bulletin 151, Truck and Garden Insects
the beets are gathered, if not before. If the infested leaves are
left in the field the grubs have opportunity to enter the ground,
go into the pupal stage and emerge later as flies.
FLEA-BEETLE
This is a small oval beetle (fig. 62) that gets its name from
the habit of quickly springing several inches when disturbed.
Two species are more or less troublesome in Florida to beets,
cabbage, cucum-
be r s, tomatoes
and related
plants. They eat
the epidermis on
one side of the
leaf and the soft
interior cells but
leave the veins
and other hard
parts.
Bordeaux
mixture is usu- a
all y efficacious
in preventing
injury by these a1 4 I
insects. The
mixture can be e
made more effi- FiG. 62.--Strawberry flea-beetle: a, Adult; b, eggs on
leaf; c, side-view of young larva; e, dorsal view of
cient by the ad- larva; f, pupa. Greatly enlarged. (From U. S. Bur.
edition of from 8
to 16 ounces of powdered lead arsenate (or 1 to 2 pounds of
the paste) to 50 gallons of the bordeaux.
STRIPED MORNING-SPHINX (Celerio lineata)
The larva of this very common hawk-moth feeds occasion-
ally on beets, altho its common host plant in Florida is purslane.
It has the size and general appearance of the tomato-worm and
belongs to the same family. Its life history is similar and the
control measures are the same.
LARGER BEET WEBWORM
There are two species of small moths of the genus Hymenia
(or Zinckenia) whose caterpillars attack the beet. The larger
one is the spotted beet webworm (Hymenia perspectalis). This
Florida Agricultural Experiment Station
larva is a small green caterpillar with purplish dots on its head.
The adult moth is a little over an inch in width across the
wings. It is cinnamon-brown in color with narrow white bands
in the middle of the front wings. The eggs are about 1/50 of
an inch in diameter and are laid on the leaves of the beets and,
particularly, carelessweed (amaranth). The latter is probably
its original host plant.
SMALL BEET WEBWORM (Hymenia fascialis)
This small webworm is much more abundant than Hymenia
perspectalis. During July the moths collect about the blossoms
of catnip and other plants in great numbers. As with the other
species the beet is a minor host plant for this insect, whose
larvae live chiefly on wild plants. The moth is smaller than
the other species and the white bands of the wings are larger.
Either species can easily be controlled with lead arsenate.
CUTWORMS
These greedy pests seem to be especially fond of beets, the
leaves of which they cut off. If this is repeated continuously
the plant is unable to grow. For control see cabbage.
OTHER BEET PESTS
Other insects which attack beets are: Wireworms (see un-
der corn, page 153) ; white grubs (see under potatoes, page 178) ;
bean-jassid (see bean leaf-hopper under beans, page 129);
harlequin cabbage-bug (see under cabbage, page 148); false
chinch-bug (see tarnished plant-bug under celery, page 149);
sweet-potato caterpillar (see under sweet potatoes, page 186);
12-spotted Diabrotica or corn root-worm (see under corn, page
158) ; and cabbage looper (see under cabbage, page 140).
CABBAGE
(Many cabbage insects also attack collards, cauliflower,
brussels sprouts, kohlrabi, and Chinese cabbage.)
CUTWORMS
Cutworms are very fond of any succulent plant, and are
troublesome to most truck and garden crops. Cabbage is one of
the chief sufferers from their attacks. They gnaw off the young
plants just above the ground, making them worthless.
Cutworms are the almost hairless larvae (fig. 63, a, b) of
any of several species of moths of the Noctuid family. The
moths are night-fliers and are commonly seen about lights. They
are grayish or brownish in color and most of them have on their
Bulletin 151, Truck and Garden Insects
fore wings small silvery markings, dots, dashes, or commas (fig.
63, d, e).
In Florida they do not hibernate but are active and breed
thruout the year, altho neither the moths nor the caterpillars
are active during the coldest nights of the winter. The cater-
pillars will remain active at a
lower temperature than the
moths, but the latter are to be
seen about lights during warm
/ evenings even in midwinter.
The worms suspend operations
cB b during the coldest nights only,
when the temperature drops
below 45 degrees.
There are no definite
broods, caterpillars of all sizes,
b eggs, and moths are to be seen
at one and the same time.
Control.- The moths by
preference lay their eggs (fig.
S 64) on grasses
in heavy sod
FIG. 63.-Cutworm moth (Mamestra land. The lar-
chenopodii): a, b, Larva; pupa; d, vae f e e d on
moth; e, wing of moth, enlarged.
Natural size. (From U. S. Bur. of t h e grasses.
Ent.)
Consequently,
on land that has had considerable grass, the cut-
worms are most troublesome. As long as the
grass is available there is so much food in pro-
portion to the number of worms that their
feeding is scarcely noticeable. But when such
land is plowed, the normal food supply of the
caterpillars is cut off and they are concentrated
upon the relatively small amount of vegetation
of the farmer's crop.
When grass land is plowed measures
should be taken to kill the cutworms present
before a crop is planted. To do this, prepare
b'
FIG. 64.-E ggs of
cutworm moth
(Agrotis saucia):
a, Single egg,
greatly enlarged;
b, egg mass on
twig. Natural
size. (From U. S
Bur. of Ent.)
the land ten days or two weeks before the cabbages are to be
set out. During that time many of the cutworms will leave or
die of starvation and the remainder develop a good appetite. A
day or two before the crop is to be set out, cut some green and
Florida Agricultural Experiment Station
succulent plants such as collards, rape, cowpeas, etc., and dip
them into a strong solution of paris green; about an ounce to a
gallon of water. Scatter this about the field after sunset, for
the hungry cutworms to feed upon during the night. Instead
of the green material the following described poisoned bait,
called the Kansas Mixture," may be used.
A Bran ..................................... .... ........- ......20 pounds
Cottonseed m eal...................... ....... ........... 5 pounds
Paris green........................ ...-. ..... ... 1 pound
B. W ater ..................-- .. -....... --...... ...--.. 21/2 gallons
M olasses or syrup. --.................. ..-... ...... 2 quarts
Lem ons ................... ...- .. ......... ....... 3 or 4
The entire lemons should be grated or ground fine. Mix
the bran, cottonseed meal and paris green thoroly while still
dry; then wet "A" with B" until it is decidedly damp, not
sloppy, and of such consistency that it will fall in fine flakes
when sown broadcast over the land. This should be put out
after sunset so that it will be fresh and attractive when the
worms come out to feed in the night. If the following day is
cloudy, the bait will remain attractive for the second night,
otherwise it will need to be renewed if the cutworms have not
been brought under control. If properly sown it will fall in
such small flakes that fowls or other birds will not pick it up.
In a cabbage field, better protection will be given to the plants
at a smaller expenditure for material if, instead of being sown
broadcast, the bait is placed in small piles about the stalks of
the cabbage. For protecting other crops it may be scattered
along the rows. Instead of both cottonseed meal and bran,
either may be used alone, in which case 25 pounds is used.
Bitter molasses, such as New Orleans, stale bran or meal, should
not be used in making this bait. The mixture must be made up
fresh each day from sweet, fresh material.
In a small garden or in a field where there are but few
cutworms, the easiest, quickest and cheapest method of dealing
with them is to walk thru the patch in the early morning and
look for plants which were cut off during the preceding night.
By scratching the earth away from the base of the plant the
culprit will usually be found at a depth of not more than an
inch. They may be collected and fed to chickens.
CABBAGE WORMS'
At least five species of caterpillars feed on cabbages and
related plants in Florida. The most common one during the
cabbage growing season, the winter, is the cabbage looper.
Bulletin 151, Truck and Garden Insects
CABBAGE LOOPER (Autographa brassicae).-This larva (fig.
65, a) of a Noctuid moth is closely related to cutworms, which
it resembles in general shape. It does not have the cutworm
manner of feeding but
works on the surface of
the cabbage leaves both
day and night. It in-
jures the leaves by eat-
ing holes in them and
also damages the ap-
pearance of the heads
by soiling them with its
---- excrement. The cater-
pillar is light green in
color and grows to a
-a. length of more than an
inch.
FIG. 65.-Cabbage looper: t, Larva; b, pupa;
,' adult. Natural size. (From U. S. Bur. The eggs, yellowish-
of Ent.)
green in color and about
a fiftieth of an inch in diameter, are scattered over the surface
of the leaves. The caterpillar requires about 3 weeks for
growth and spends about 2 weeks in the pupa stage.
The adult moth fig. 65, c) also looks much like those of
cutworms, and, in the latitude of Gainesville, may be active all
winter.
THE CABBAGE PLUTELLA* (Plutella maculapennis).- The
cabbage plutella (fig. 66, a), a much smaller caterpillar than
the looper, is common on
cabbages. It is less than
a half-inch long and is
much more hairy in ap-
pearance than the loop- c
er. When disturbed it
drops quickly from the
plant, spinning a silken d
thread which it uses to
remount when the dan- e
ger is over. On the un- FIG. 66.-Cabbage plutella: a, Larva; d, e,
pupa; f, moth: h, moth at rest. Two
der side of the leaf, it and one-half times natural size. (From
U. S. Bur. of Ent.)
makes small round holes,
rarely extending thru. Like the looper, this caterpillar is active
*For life history, see page 202.
Florida Agricultural Experiment Station
all winter in the latitude of Gainesville and south. The cocoon
placed on the leaf is a loosely-woven affair thru which the pupa
(fig. 66, e) may be seen plainly.
The adult (fig. 66, f) is a small moth 5/8 of an inch across
the expanded wings, which are gray with a border of lighter
areas. When the wings are folded in the resting position (fig.
66, h) these areas form diamond-shaped patches along the back.
For this reason the moth is also called the "diamond-back" moth.
CABBAGE BUTTERFLIES
The caterpillars of these white butterflies are injurious to
late cabbage and collards. They do not seriously trouble the
main winter-grown crop of cabbage because they
are not active at that season.
IMPORTED CABBAGE-WORM (Pontia rapae).-
In the northern and western parts of the State
the most common cabbage butterfly is the im-
ported cabbage-worm, a pest which was brought
to this country about 1856. It has since spread
over the entire country, reaching Florida about
1890, but has never become as abundant as in
the Northern States.
The full-grown caterpillar (fig. 67, a) is
about 114 inches long, bright green with a FGor 6e7--mb-
yellowish line down the middle of its back and bage butter-
fly: a, Larva;
a row of spots of the same color along its b, pupa. Nat-
ural size.
sides. Two or three weeks are required for (From U. .n
its growth. It then crawls to some sheltered
place and there transforms into the pupa (fig. 67, b) and 8 or
10 days later, in warm weather, the butterfly (figs. 68, 69)
emerges. But those which enter the pupa stage in the late fall
FIG. 68.-Imported cabbage but FIG. 69.-Imported cabbage butter-
terfly: Female. Natural size. fly: Male. Natural size. (From
(From U. S. Bur. of Ent.) U. S. Bur. of Ent.)
remain there all winter, at least in the northern part of the
State. The eggs are white or yellow in color and are scattered
over the surface of the leaf.
Bulletin 151, Truck and Garden Insects
NATIVE OR SOUTHERN CABBAGE-WORM (Pieris protodice).-
This worm (fig. 72, a) is similar in appearance to the imported
worm but has four longitudinal yellow bands. The butterflies
can be distinguished by comparing the illustration's (figs. 68, 69,
70, 71). The nature of the injury it inflicts is identical with
that of the species last named.
FIG. 70.-Southern cabbage butter- FIG. 71.-Southern cabbage butter-
fly: Male. Natural size. (From fly: Female. Natural size. (From
U. S. Bur. of Ent.) U. S. Bur. of Ent.)
GULF WHITE (Pieris monuste).-This butterfly has a yel-
low caterpillar (fig. 73, a) with four longitudinal stripes of a
purplish hue. It is 1 inches long. The butterfly (fig. 73, c)
is the largest of the group, measuring nearly 3 inches across
the expanded wings. This is by far the most common and
troublesome caterpillar on cabbage and collards grown during
the late spring and sum-
mer in the southern part
of the State.
Control.-Any or all
of these caterpillars are
easily controlled by means a
of arsenicals. One can use
paris green but either lead
arsenate or zinc arsenite
is preferable. One pound of FIG. 72.-Southern cabbage butterfly: a.
paris green or 2 pounds of Larva; b, pupa. Natural size. (From
U. S. Bur. of Ent.)
lead arsenate or zinc arsen-
ite powder is put into 50 gallons of water. This liquid usually
does not stick well to cabbage plants on account of the "bloom,"
a waxy coating. To make it stick, add soap when the mixture
is made, at the rate of 5 or 6 pounds for 50 gallons of water,
according to whether the water is hard or soft. Any alkaline
laundry soap will do. Flour-paste is also a good substance to
make the arsenic compound stick to cabbage leaves. A paste
Florida Agricultural Experiment Station
made by boiling 2 pounds of flour in 2 gallons of water may be
added to 50 gallons of the arsenical solution. (See also page
202).
A new spreader worked out by the U. S. Department of
Agriculture is a solution of cactus. Thirty pounds of cactus is
chopped fine and allowed to soak over night in 50 gallons of
water. This is strained and the arsenic added. In those parts
of the State where some of the wild species of prickly pears"
or spineless cactus grow, this should make a cheap "sticker."
Arsenical poisons may be used dry if applied when the
cabbages are wet with dew or rain. It is well to use a filler of
cheap flour or
air-slacked
li m e, mixing
about sixteen
parts of the
filler to one of
dry poison.
Of the
three com-
pounds, z i n c
arsenite is the
least poisonous
to man or stock.
Paris green is
the least satis-
factory. Its
arsenic content
I is variable and
FIG. 73.-Gulf white butterfly: a, Larva; b, pupa; c, adult, it may burn
Natural size. (From U. S. Bur. of Ent.)
tender plants.
In some quarters there is a prejudice against using arsenicals
on cabbages on account of the supposed danger to the consumer.
The amount adhering to the cabbage is so minute as not to
affect the health of the consumer in any way. A prominent
entomologist has calculated that in order to be poisoned by
eating even unwashed cabbages which had been sprayed with
paris green one would have to eat a dozen heads at a sitting.
Ordinarily a rain will wash off so much of the material that it
will not be noticed.
If the presence of the arsenical is likely to hinder the sale
of cabbages, it is recommended that they be not sprayed within
Bulletin 151, Truck and Garden Insects
ten days of the time of harvest. By using zinc arsenite instead
of lead arsenate, one can still further reduce the likelihood of
danger to the consumer, since zinc arsenite is less poisonous to
man. The common idea that a cabbage "heads up" by the
leaves curling inward is a mistake. The head is formed entirely
by internal growth; in fact, it is but a big bud and is formed
like other buds, never by the folding up of leaves. Conse-
quently, there is no danger of the poison being carried into the
interior of the head and held there on the leaves.
CABBAGE PLANT-LICE
The common aphid on cabbage is the garden aphid or so-
called green peach-aphid (Myzus persicae), altho the cabbage
plant-louse (Aphis brassicae) (fig. 74) and the turnip louse
(Aphis pseudo-brassicae) are also found.
The garden aphid is bright green in color and smooth,
while the -others have a
more mealy look, and the
turnip louse is quite hairy.
The character of the dam-
S.. age, the life history, and
the means of control are
the same for all three
species and practically the
FIG. 74.-Cabbage-aphis: a, Winged fe- same for all aphids.
male; b, wingless female. Greatly en- Aphids suck the juices
large. (From U. S. Bur. of Ent.)
from the plant on which
they live, stunting its growth, causing the leaves to curl,
turn yellow, and finally, the plant to die. They multiply
with great rapidity, often beginning when only a week old
and producing several young each day. During warm weather,
which means the entire year in Florida, the individuals of
most species bring forth young parthenogenically, that is,
without mating between the sexes. Indeed, during that time of
the year males are usually not produced at all. Usually the
young are born alive and active, the eggs hatching before they
are laid. But with the coming of winter, in more northern
states, males and true females are produced and eggs are laid
which do not hatch until spring. Most individuals never acquire
wings, but from time to time winged individuals are produced
and spread the species from plant to plant.
Farther north the green peach-aphid spends the winter in
the egg stage on peaches, plums, etc. The first two or three
Florida Agricultural Ex.periment Station
generations in the spring feed on the tender unfolding buds of
those trees. The first generation is pink in color but their
young are green and never become pink. The second or third
generations usually develop wings and leave the trees for tender
vegetables where they live all summer. This annual migration
is common among aphids, and the last generation returns to
the trees in the fall to lay eggs, enabling the species to get an
earlier start in the spring than would be possible were it neces-
sary to wait for herbs to grow.
Aphids give off a sweet substance called honeydew of which
ants are very fond. For the sake of this honeydew ants care-
fully tend aphids, often protecting them from their enemies
which they drive away. They may carry the aphids or their
eggs from place to place where the pasture is good, carry
the eggs into their nests to winter over, or even build adobe
sheds over them for protection from rain and enemies. For
this reason aphids are often called ants' cows." Hence it
happens that the presence of excited ants on a plant is often
the most evident sign of the presence of aphids.
Remedies.-For the control of aphids on cabbage, the best
remedy is to spray the plants with a solution of tobacco ex-
tract. For directions for making this see melon aphis under
watermelons, page 199. On cabbages a spreader of soap and
flour-paste should be used as recommended in the discussion of
cabbage worms. If the worms and the aphids are both present
on the cabbages, the tobacco can be added to the lead arsenate
spray, killing both pests at one time.
Dusting the plants with tobacco dust is of some benefit, and
will often keep down the number of aphids and prevent an
outbreak, but will not control effectively an outbreak that has
gained headway. These outbreaks often start on plants scat-
tered thru a field and by pulling them up and destroying them,
a general outbreak can be forestalled or at least delayed.
Enemies.-Aphids are a very attractive article of diet to a
large number of enemies which are usually able to hold them in
check. Only the wonderful rate of reproduction of the aphids
enables them to have a surplus with which to start a destructive
outbreak after supplying the market" of their enemies.
The smaller birds such as wrens, fly-catchers, and warblers
destroy great numbers of aphids. A flock of young chickens,
if given the freedom of the garden, will do excellent work in
ridding it of aphids.
Bulletin 151, Truck and Garden Insects
In a colony of aphids, dead ones may be found which are
so greatly swollen as to be nearly spherical in shape. These
have been killed by the larva of a minute wasp-like parasite
which lives in the interior of the aphid, consuming its vitals.
The parasite pupates in the dead aphid and when the adult
parasite is ready to emerge it bites a hole in the top of the
aphid and crawls out. The egg from which the parasitic larva
hatches is laid inside the aphid which the female parasite
pierces with her ovipositor.
Several kinds of soft-bodied larvae move among the aphids
and destroy them. One is a dirty white legless maggot which
impales aphids on its sharp anterior end and sucks the body
fluids. This is the larva of a family of two-winged flies known
as syrphus-flies. There are many species. Another is flat,
pale, wedge-shaped, with well-developed legs and a pair of jaws
with which it pierces the aphids. These are aphid-lions. The
adults are lace-winged flies (Chrysopa), bright green insects
which measure nearly an inch across the four gauzy wings and
have bright golden eyes. The eggs are laid in groups and are
raised on stalks a half-inch above the surface of the leaf. This
arrangement prevents those first born from using for their
food the unhatched eggs in the group. A similar larva (Heme-
robius) makes a case to cover its body out of the remains of
the victims which it has sucked dry. This case is carried about
by the larva, hence it is called a "trash-bug." The adult is
similar to the golden-eyed lace-wing, but is brown.
Aphids are the choice food of many lady-beetles and their
larvae. The species most common in Florida truck patches and
gardens are the convergent lady-beetle and the 9-spotted lady-
beetle, altho the twice-stabbed lady-beetle, so common and bene-
ficial in citrus groves, is occasionally found.
During the rainy season aphids are subject to attack by
fungi, particularly Empusa aphidis. This fungus often destroys
in a few days the aphids from whole fields.
The heavy rains of the Florida summer are directly de-
structive to aphids which are knocked off the plants and beaten
to death on the ground.
CABBAGE ROOT-MAGGOT (Phorbia fuscipes)
These small, soft-bodied legless maggots (fig. 75, a) often
do great damage to the roots of cabbage and related plants
upon which they feed. The first indications of their presence
on the roots are a check to the growth of the plants which wilt
Florida Agricultural Experiment Station
during the heat of the day and show a bluish, sickly color. The
plants finally turn yellow and wilt down completely. If these
plants are pulled up it is found that the roots have been eaten
off, and perhaps the main stem mined, by the maggots which
are about /4 of an inch long when fully grown.
The adult (fig. 75, c) is a two-winged fly, similar in Ap-
pearance to the house- or typhoid-fly but much smaller and with
a proportionally longer abdomen. The female lays her eggs on
the stem of the plant or on the ground near by.
Remedies.-Repellants placed about the roots of the plants
when first set out are of some benefit in discouraging the females
from laying their eggs
Son the plants. Perhaps
tobacco dust is about as
practicable as any. Car-
bolic acid emulsion may
be used. Liberal fertili-
zation will enable the
\ j Jplants to outgrow the
Jc damage done by a few
e maggots. Repeated shal-
l ow cultivation will de-
stroy many of the eggs
Sa laid on the ground about
the bases of the plants.
FIG. 75.-Cabbage root-maggot (Phorbia The grower should de-
brassicae): a, Larva; b, pupa; c, female gr
fly. About four times natural size. (From stroy all heavily-infested
U. S. Bur. of Ent.)
plants and should avoid
planting cabbage on land that has just borne a crop of
infested cruciferous plants whether cabbage, cauliflower, col-
lards, rape, mustard, or turnips. The maggot will breed in
wild plants of this family and all such found near the field
should be destroyed.
Cabbages in an infested seed bed can be treated with car-
bon bisulphide. To do this, make holes with a stick three or
four inches from the infested plant and slanting obliquely under
it. Pour in about a teaspoonful of the carbon bisulphide and
quickly tramp the soil solid to confine the fumes.
In the Northern States it has been found profitable after
setting the plants in the field to protect them from the attacks
of this insect by using tarred paper discs. These are cut open
along one radius and fitted closely about the plant. It is doubt-
Bulletin 151, Truck and Garden Insects
ful if the attacks of the insect in Florida fields are sufficiently
common to make this precaution profitable except in the case
of some particularly valuable plants.
HARLEQUIN CABBAGE-BUG OR CALICO-BACK
(Murgantia histronica)
This strikingly-colored insect, a native of the Mexican re-
gion, has been slowly working its way eastward and northward.
It is not as yet abundant in Cy
Florida but may be seen occa-
sionally on late cabbage and is
quite common and destructive to
collards that are carried thru d "
the summer.
The adult (fig. 76, g) is
black and orange and is 2/5 of
an inch long. Both the adult
and young suck the juices of the FIG. 7.-Harlequin cabge-bug: a,
plants into which they inject a b, Nymphs; d, e, eggs, greatly en-
larged; f, g, adults. Slightly en-
poison. A few bugs are suffi- large. (From U. S. Bur. of Ent.)
cient to cause a plant to turn yellow and die.
The eggs (fig. 76, c, d, e) are deposited on the under side
of the leaves, usually in two rows. They are keg-shaped, white,
with black bands and a small
black spot on each side, increas-
ing the resemblance to a keg
with its hoops and bung-hole.
They hatch in 3 or 4 days. The
young are at first yellow, devel-
oping the orange markings later.
They are usually present in
such number as to make hand
collecting practical, but hand
FIG. 77.-Cabbage hair-worm or cab- collecting of the young is less
bage snake. (From U. S. Bur. of Ent.)
satisfactory because of their
small size. Should these become abundant they can be killed
by kerosene emulsion. Destroy all infested, dying plants. in
the northern part of the State a crop of late cabbage can be
partly protected by planting an early trap crop of mustard,
radishes or turnips. When this trap crop becomes infested
it may be sprayed with kerosene emulsion or pulled up and
burned.
Florida Agricultural Experiment Station
CABBAGE HAIR-WORM OR CABBAGE SNAKE (Mermis albicans)
This whitish, thread-like worm (fig. 77), which sometimes
grows to be 2 to 9 inches long, is frequently found in cabbage
heads. It is an internal parasite of grasshoppers and cater-
pillars and it gets into the cabbage by crawling out of infested
insects. It is therefore a friend of the grower. In spite of its
repulsive looks and the many stories which are told of its pois-
onous nature, it is entirely harmless to mankind.
SOUTHERN SQUASH BUG (Anasa armiger)
This insect sometimes attacks cabbage and collards. It
breeds on these plants, as eggs and nymphs are found there.
OTHER CABBAGE PESTS
The following named insects also infest cabbage in Florida:
Blister-beetles (see under beets, page 134) ; flea-beetles (see un-
der beets, page 136) ; tarnished plant-bug (see under celery,
page 149); onion thrips (see under onions, page 172); wire-
worms (see under corn, page 153) ; nematodes (see root-knot
under general garden pests, page 128) ; and grasshoppers (see
under general garden pests, page 122) ; serpentine leaf-miner
(see under cowpeas, page 162).
CANTALOUPE
The insect pests of this crop are identical with those of
cucumbers. (See cucumbers, page 163).
CARROT
The common insect pests of this crop are: Cutworms (see
under cabbage, page 137) ; garden aphid (see cabbage plant-lice
under cabbage, page 144) ; black blister-beetle (Epicauta penn-
sylvanica) (see blister-beetles under beets, page 134; celery
caterpillars (see under celery, page 150) ; and carrot-beetle
(Ligyrvs gibbosus) (see May-beetles under potatoes, page 178).
CELERY
TARNISHED PLANT-BUG (Lygus pratensis)
This bug (fig. 79) is very common the country over in
gardens where it frequents blossom heads and other very young
and tender herbage and even the tender shoots of trees. The
succulent stalks of the celery plant afford a very acceptable
feeding place. In addition to stunting the growth of the plant,
Florida Agricultural Experiment Station
CABBAGE HAIR-WORM OR CABBAGE SNAKE (Mermis albicans)
This whitish, thread-like worm (fig. 77), which sometimes
grows to be 2 to 9 inches long, is frequently found in cabbage
heads. It is an internal parasite of grasshoppers and cater-
pillars and it gets into the cabbage by crawling out of infested
insects. It is therefore a friend of the grower. In spite of its
repulsive looks and the many stories which are told of its pois-
onous nature, it is entirely harmless to mankind.
SOUTHERN SQUASH BUG (Anasa armiger)
This insect sometimes attacks cabbage and collards. It
breeds on these plants, as eggs and nymphs are found there.
OTHER CABBAGE PESTS
The following named insects also infest cabbage in Florida:
Blister-beetles (see under beets, page 134) ; flea-beetles (see un-
der beets, page 136) ; tarnished plant-bug (see under celery,
page 149); onion thrips (see under onions, page 172); wire-
worms (see under corn, page 153) ; nematodes (see root-knot
under general garden pests, page 128) ; and grasshoppers (see
under general garden pests, page 122) ; serpentine leaf-miner
(see under cowpeas, page 162).
CANTALOUPE
The insect pests of this crop are identical with those of
cucumbers. (See cucumbers, page 163).
CARROT
The common insect pests of this crop are: Cutworms (see
under cabbage, page 137) ; garden aphid (see cabbage plant-lice
under cabbage, page 144) ; black blister-beetle (Epicauta penn-
sylvanica) (see blister-beetles under beets, page 134; celery
caterpillars (see under celery, page 150) ; and carrot-beetle
(Ligyrvs gibbosus) (see May-beetles under potatoes, page 178).
CELERY
TARNISHED PLANT-BUG (Lygus pratensis)
This bug (fig. 79) is very common the country over in
gardens where it frequents blossom heads and other very young
and tender herbage and even the tender shoots of trees. The
succulent stalks of the celery plant afford a very acceptable
feeding place. In addition to stunting the growth of the plant,
Florida Agricultural Experiment Station
CABBAGE HAIR-WORM OR CABBAGE SNAKE (Mermis albicans)
This whitish, thread-like worm (fig. 77), which sometimes
grows to be 2 to 9 inches long, is frequently found in cabbage
heads. It is an internal parasite of grasshoppers and cater-
pillars and it gets into the cabbage by crawling out of infested
insects. It is therefore a friend of the grower. In spite of its
repulsive looks and the many stories which are told of its pois-
onous nature, it is entirely harmless to mankind.
SOUTHERN SQUASH BUG (Anasa armiger)
This insect sometimes attacks cabbage and collards. It
breeds on these plants, as eggs and nymphs are found there.
OTHER CABBAGE PESTS
The following named insects also infest cabbage in Florida:
Blister-beetles (see under beets, page 134) ; flea-beetles (see un-
der beets, page 136) ; tarnished plant-bug (see under celery,
page 149); onion thrips (see under onions, page 172); wire-
worms (see under corn, page 153) ; nematodes (see root-knot
under general garden pests, page 128) ; and grasshoppers (see
under general garden pests, page 122) ; serpentine leaf-miner
(see under cowpeas, page 162).
CANTALOUPE
The insect pests of this crop are identical with those of
cucumbers. (See cucumbers, page 163).
CARROT
The common insect pests of this crop are: Cutworms (see
under cabbage, page 137) ; garden aphid (see cabbage plant-lice
under cabbage, page 144) ; black blister-beetle (Epicauta penn-
sylvanica) (see blister-beetles under beets, page 134; celery
caterpillars (see under celery, page 150) ; and carrot-beetle
(Ligyrvs gibbosus) (see May-beetles under potatoes, page 178).
CELERY
TARNISHED PLANT-BUG (Lygus pratensis)
This bug (fig. 79) is very common the country over in
gardens where it frequents blossom heads and other very young
and tender herbage and even the tender shoots of trees. The
succulent stalks of the celery plant afford a very acceptable
feeding place. In addition to stunting the growth of the plant,
Florida Agricultural Experiment Station
CABBAGE HAIR-WORM OR CABBAGE SNAKE (Mermis albicans)
This whitish, thread-like worm (fig. 77), which sometimes
grows to be 2 to 9 inches long, is frequently found in cabbage
heads. It is an internal parasite of grasshoppers and cater-
pillars and it gets into the cabbage by crawling out of infested
insects. It is therefore a friend of the grower. In spite of its
repulsive looks and the many stories which are told of its pois-
onous nature, it is entirely harmless to mankind.
SOUTHERN SQUASH BUG (Anasa armiger)
This insect sometimes attacks cabbage and collards. It
breeds on these plants, as eggs and nymphs are found there.
OTHER CABBAGE PESTS
The following named insects also infest cabbage in Florida:
Blister-beetles (see under beets, page 134) ; flea-beetles (see un-
der beets, page 136) ; tarnished plant-bug (see under celery,
page 149); onion thrips (see under onions, page 172); wire-
worms (see under corn, page 153) ; nematodes (see root-knot
under general garden pests, page 128) ; and grasshoppers (see
under general garden pests, page 122) ; serpentine leaf-miner
(see under cowpeas, page 162).
CANTALOUPE
The insect pests of this crop are identical with those of
cucumbers. (See cucumbers, page 163).
CARROT
The common insect pests of this crop are: Cutworms (see
under cabbage, page 137) ; garden aphid (see cabbage plant-lice
under cabbage, page 144) ; black blister-beetle (Epicauta penn-
sylvanica) (see blister-beetles under beets, page 134; celery
caterpillars (see under celery, page 150) ; and carrot-beetle
(Ligyrvs gibbosus) (see May-beetles under potatoes, page 178).
CELERY
TARNISHED PLANT-BUG (Lygus pratensis)
This bug (fig. 79) is very common the country over in
gardens where it frequents blossom heads and other very young
and tender herbage and even the tender shoots of trees. The
succulent stalks of the celery plant afford a very acceptable
feeding place. In addition to stunting the growth of the plant,
Bulletin 151, Truck and Garden Insects
due to the insect sucking the sap, brown spots are produced
where the punctures are made. These greatly reduce the at-
tractiveness of the produce on the market.
The adult bug is only about 2/5 of an inch long. The male
is dark reddish-brown and the female light brown with light
yellow markings. They
breed rapidly. The young -
(fig. 78) are greenish in "
color. These bugs are rather
restless and are quick in /
their movements. For this G. 78.-Tarnished plant-bug: Immature
reason they are most easily stages. Four times natural size. (From
U. S. Bur. of Ent.)
captured or killed in the
early morning when they are relatively sluggish. A strong
tobacco extract with plenty of soap will kill the young and most
of the adults but kerosene emulsion is better.
A number of other bugs, such as False Chinch-bug (Nysius
angustatus), frequently attack celery. The character of the
injury is similar to that of the tarnished plant-bug and the
control measures identical.
CELERY CATERPILLAR (Papilio polyxenes)
This caterpillar sometimes strips the leaves from celery
and, as the caterpillar is rather large, a single one can inflict
much damage. It is con-
V V spicuously colored in green
and black. It is a close
1 relative to the common
Si "orange dog" (Papilio
cresphontes) and, like that
species, when disturbed, it
Sthrusts out a yellow horn-
like process from the head
FIG. 79.-Tarnished plant-bug: Adult and
young. About four times natural size. accompanied by a strong
(From U. S. Bur. of Ent.) pungent odor. This seems
to protect the insect from birds and possibly other foes. It
grows to a length of 2 inches. The pupa is fastened to a sup-
port partly by a silken thread about its middle. In from 12 to
15 days, in summer, there issues from it a swallow-tailed but-
terfly. This is smaller than the adult of the orange dog and
much darker in color. It is called the black swallow-tail.
Both the caterpillar and its work are so conspicuous that
hand-picking will usually be the most economical means of
Florida Agricultural Experiment Station
control. As celery is commonly sprayed with bordeaux for fungus
troubles, lead arsenate can be added (1 pound to 50 gallons of
bordeaux) and this, as well as all other biting insects, be killed.
OTHER CATERPILLARS.-Several other caterpillars attack
celery; among them are the celery looper (Plusia simplex), an
insect closely related to the cabbage looper, and the celery leaf-
tyer (Phlyctaenia ferrugalis).
PLANT-LICE
At least two species of aphids commonly attack celery in
Florida. One is the common garden aphid or green peach-
aphid (Myzus persicae). The other, Macrosiphum lactucae is
much larger. The control measures are the same as those given
under cabbage, page 144.
OTHER CELERY PESTS
Other insects injurious to celery are: Flea-beetle (see un-
der beets, page 136) ; cutworms (see under cabbage, page 137);
and cabbage root-maggot (see under cabbage, page 146).
FIELD CORN AND SWEET CORN
Sweet corn is attacked by all the common pests of corn and
there are many of them. Some show a decided preference for
sweet corn. Only the more important insects attacking corn
will be considered here.
CORN EAR-WORM, OR BUD-WORM (Heliothis obsoleta)
This common pest of cotton, corn, tomatoes, beggarweed,
etc., prefers sweet corn to any other of its host plants. Early
in the season the moth lays her eggs on the young corn. The
early generation of larvae which hatches from these eggs works
in the corn as a bud-worm." (At least two other caterpillars
that do very similar damage to corn are known as bud-
worms.") When mature the caterpillars enter the ground,
pupate, and in seven days emerge as moths which in turn lay
their eggs on the silk of the corn which is by this time begin-
ning to appear. The second generation of larvae on the corn
eats the silk and then enters the ear and feeds upon the devel-
oping kernels. Later generations develop on cotton, beans,
beggarweed, etc. The insect also attacks tomatoes. But whether
working in corn as the bud-worm" or ear-worm," in toma-
toes as the fruit-worm," on cotton as the bollworm," or fully
exposed on beggarweed, it is the same insect. So abundant is
this pest in Florida that it is almost impossible to find an ear of
Bulletin 151, Truck and Garden Insects
sweet corn that has not been attacked by at least one of these
caterpillars.
Control.-The work of the first generation in the corn is
usually noticeable when the corn is about knee high. At this
stage it is not difficult to poison the caterpillars by spraying or
dusting some of the arsenic compounds into the infested buds.
The writer has dusted undiluted lead arsenate and zinc arsenite
powder into the buds without producing any harmful effects, but
it is safer and more economical to mix the poison with from 2
to 4 times its bulk of air-slacked or hydrated lime. The dusting
is best done in the early morning when the plants are wet with
dew. The agitation resulting from brushing against the stalks
will usually be sufficient to cause the dew to run down into the
bud, carrying the poison with i
can be applied by means of a
tin can punched full of holes.
On a large scale the well-
known bag-and-pole method
may be used, but the most
even distribution will be se-
cured by the use of a dusting
machine. It is important that
this early generation should
be destroyed, if possible. Not
only will the injury to the
buds be checked, but the
t. In a small garden the poison
\.
FIG. 80.-Corn ear-worm: Adult. One
and a half times natural size. (Or-
iginal.)
number of caterpillars in the following generation, which
works in the ears, will be lessened.
When the silks appear on the young ears of corn they can
be dusted by means of the same apparatus. The caterpillars feed
on the exposed silks for only a few days before entering the ear,
where they are safe from insecticides, so it will be necessary
to repeat the dusting every three or four days. This is too
expensive for a crop of field corn, but on such a high-priced
crop as sweet corn it is worth while.
In a small patch in the garden the worms can often be
removed from the tip of the ear before they have inflicted mate-
rial damage. In removing the worms it is not well, however,
to open the ears to such an extent as to expose the kernels, as
other animals such as birds, Carpophilus and other beetles, and
insects will then attack them. Woodpeckers and bluejays are
occasionally seen feeding on theworms and the ears of sweet corn.
Florida Agricultural Experiment Station
Life History.-The eggs are whitish, oval, prominently
ribbed, and about a twentieth of an inch in diameter. They are
scattered over the corn. Those from which the bud-worm
hatches are laid on the leaves; those of the ear-worm on the
silk. They hatch in 3 or 4 days.
The caterpillars vary from a delicate pink to black. They
are marked with rather narrow longitudinal lines. They require
about 17 days for growth in summer, becoming 11 to 2 inches
long. The caterpillar then bores a hole in the side of the ear
or stalk and enters the ground to a depth of 2 to 5 inches where
it forms the pupa. Here it remains for a week or two in summer
or all winter if it is the last fall brood.
The pupa lies in an earthen cell. It is about /4-inch long.
It is at first green in color but soon turns to a light brown. The
moth (fig. 80) which issues from this cocoon varies in color
from a dusky yellow to grayish and expands from 11/a to 2
inches. Unlike most moths it may fly in broad daylight, but
the eggs are usually laid at sunset.
CARPOPHILUS
If the husk is removed from an ear of corn in the milk by
any cause, such as a woodpecker in his hunt for a corn ear-
worm, it is at once attacked by these scavenger beetles, which
are also common in decaying fruits. The beetles are brown
and about 1/8 of an inch in length. Their wing-covers are so
short that they do not reach the end of the abdomen. The
beetles seem unable to penetrate the husk of an uninjured ear,
but very commonly get into the burrows made by the corn ear-
worm and cause further damage. They often breed among the
kernels which blacken and decay, thus spoiling many ears that
would otherwise be usable. The larvae are small, whitish, and
maggot-like. Control measures are obviously those which con-
trol the corn ear-worm.
WIREWORMS, "DRILLWORMS"
These long, slender, hard, wiry worms" are the larvae
of click-beetles. They feed below the surface of the ground on
the roots and stems of plants into which they often bore. The
infested plant is stunted, turns yellow and may die. The larvae
are particularly destructive to sprouting seed, eating the
inside.
The adults are called click-beetles from their habit of
throwing themselves into the air with an audible click when
Bulletin 151, Truck and Garden Insects
placed on their backs. They are also called skip jacks" and
" snap beetles."
There are dozens of species of wireworms in Florida and
at least a half-dozen injure corn. As their habits, life history,
type of soil infested, and control measures differ for each
species, it will be necessary to take up the more important ones
separately.
SPOTTED CLICK-BEETLE.-The most common wireworm in
Florida corn fields is the young of the spotted click-beetle
(Monocrepidius vespertinus) (fig. 81). This is a thick wire-
worm about 1/2-inch long and is found in both dry and wet land
FIG. 81.-Spotted click-beetle: Adult; pupa; larva; and egg, greatly enlarged.
(From So. Car. Agr. Exp. Sta.)
but is more destructive in the former. It is also found on
cowpeas.
The eggs are laid in the summer. They hatch in about 9
days according to Dr. A. F. Conradi and H. C. Edgerton (So.
Car. Agr. Exp. Sta. Bul. 179), and the larvae feed until the
following spring when they pupate in the ground at a depth of
from 3 to 5 inches, remaining there about 2 weeks. The earliest
adults were taken at Gainesville on June 7 by Mr. Dozier. They
are from 1/5 to 1/3 of an inch long.
Fall plowing and frequent cultivation of the corn will de-
stroy many of these insects, particularly if chickens or other birds
follow the plow. They are seldom found at a greater depth than
4 inches. A few seeds of cotton planted at the same time as the
corn is said to be of benefit. They prefer the cotton to the corn
and while they are feeding on the cotton, the corn has an oppor-
tunity to germinate and get a start.
154
Florida Agricultural Experiment Station
The nighthawk is an important enemy of the beetles which
fly at dusk, the time when these birds are on the wing. Night-
hawks should be protected by the farmer.
MONOCREPIDIUS LIVIDUS.-Associated with the last-named
species in about the same class of soil is Monocrepidius lividus.
This is perhaps the second most common wireworm in Florida.
Control measures are the same as for the above named species.
CORN AND COTTON WIREWORM.-Unlike most wireworms,
this one (Horistonotus uhleri, Horn) works mostly in sandy,
light, dry soils. It differs also from the other species in its
appearance. It is long and white and has a soft skin instead
of the hard, chitinous covering like the others. Control meas-
ures are about the same as those used against the larva of the
spotted click-beetle.
CORN WIREWORMS (Melanotus sp.).-These are not as com-
mon as the other species. Like most species of wireworms they
are found mostly in low, poorly-drained land, especially if it
was in grass the previous year. Draining and liming the land,
with deep and thoro cultivation, are important.
The larvae are about 11/4 inches long, brown in color and
have three small projections on the posterior end. Some species
require several years for growth. The adults are brown and
from a half to 3/4 of an inch in length.
OTHER WIREWORMS sometimes injurious to corn in Florida
are Lacon curtus and Lacon rectangularis. The control meas-
ures are similar to those for the last-named.
FALL ARMY WORM, OR SOUTHERN GRASS WORM
(Laphygma frugiperda)
This well-known pest of grass attacks corn as a second
choice when all of the grass within easy range has been eaten.
Army worms are so named from their habit of assembling in
vast numbers and marching in mass formation to new pastures.
These marches come as a result of excessive numbers, exhaust-
ing the food supply in the place where they hatched. The word
fall" was prefixed by entomologists in the Northern States
and is a misnomer in Florida. The destructive armies usually
form in July and August, but sometimes as early as April. At
other seasons, and during the years when no armies are formed,
a few of these caterpillars are found,feeding apart like cutworms.
Control.-These isolated caterpillars may get into the tips
of growing corn and become bud-worms" where they may be
Bulletin 151, Truck and Garden Insects
controlled by the same measures as given for the corn ear-
worms when working as bud worms. (See page 151.) The
armies may be repelled with fair success by the Kansas bait,"
or the food-plants may be sprayed or dusted with lead arsenate,
paris green or any other arsenical. This is applied best while
the caterpillars are working ongrass, before enteringthecornfield.
The eggs are laid mostly on grasses in masses of fifty or
more and hatch in about ten days. The caterpillars require
about two weeks in which to become full-size, which is about
11/4 inches long. They are rather slender. Their color is brown
with a narrow yellowish-gray stripe along the middle of the
back and a brownish-black one along the side. On the head the
central line branches, making a conspicuous V-shaped white
mark, which helps to identify the caterpillar. The body is
covered with small black prominences from each of which a
short, stiff, black hair arises. The adult is a moth resembling
those of cutworms, to which it is closely related.
ROOT WEBWORMS (Crambus sp.)
These also are caterpillars that often do severe damage to
young corn in the spring. In April, 1914, they destroyed many
FIG. 82.-Bill-bug (Sphenophorus callosus): a, Larva; d, adult. Greatly en-
larged. (From U. S. Bur. of Ent.)
acres about Gainesville and other places. They always do more
damage than they are charged with, much of their work being
attributed to cutworms. There are several species of these
insects, but all of the caterpillars are reddish, pinkish or brown,
with conspicuous dark spots on their backs. Like cutworms,
Florida Agricultural Experiment Station
they feed at night, but do not cut the plant off. Instead, they
strip it of its leaves, make channels on the surface of the stalk,
or mine the center. They construct a tube of silk just below
the surface of the ground and hide in this
during the day. This will distinguish them
from cutworms. Furthermore, they try to
escape when disturbed instead of curling up
and playing possum" like cutworms. The
adult insects are small, light-colored moths
which are always plentiful in sod land. When
at rest they roll their wings around their
bodies instead of laying them back more or
less flat like most
moths.
Cont rol.-Se-
vere injury by these
caterpillars is con-
fined to land which
had considerable
grass during the iih
p r e c e di ng year.
Such land if intend-
ed for corn should
be broken as early
in the fall as prac-
ticable. Aside from
the matter of insect
control this is also 1
the best procedure s
from the cultural a ,
standpoint, a s i t
conserves the mois- FG. 83.-Injury to corn by bill-bugs. (From
U. S. Bur. of Ent.)
ture during the dry
winter. Some relief can be obtained by dusting or spraying the
young plants with lead arsenate.
BILL-BUGS (Sphenophorus spp.)
Other insects that injure young corn are species of snout
beetles called "bill-bugs" (fig. 82). They feed on the young,
tender leaves, making parallel rows of holes, after the pattern
of sap-suckers on trees (fig. 83). This is done when the leaf
is rolled up in the bud and each row of holes is produced by a
single puncture.
158 Bulletin 151, Truck and Garden Insects
Like the last-named insect, this one is injurious only on
land that grew much grass during the preceding year. Eggs
are laid on grasses in low wet land, where alone bill-bug injury
is ever severe. The young feed chiefly on the roots of grasses, but
one species (S. robustus) may live in the pith of the corn stalk.
The measures recommended for use against root webworms
(page 156) are also the ones to be used against bill-bugs.
CORN-LEAF BLOTCH-MINER (Agromyza parvicornis)
This larva of a minute black fly makes irregular shaped
blotches in the leaves of corn and some grasses by eating the
tissue from between the lower and the upper epidermis. Its
injuries are most noticeable and serious on young corn. The egg
is laid in the corn leaf and hatches in 3 or 4 days in summer.
The larva feeds from 3 to 12 days in summer. It breeds during the
winter in southern Florida (J1. Agr. Research, April 12, 1916).
The insect cannot be reached by any insecticide. The only
course is to pull up and destroy badly infested plants, and by
good care, keep the others in such a vigorously growing condi-
tion as to overcome the injury. An excess of corn should be
planted so that a good stand will remain after the requirements
of the flies have been met and the infested plants pulled up.
SOUTHERN CORN ROOT-WORM (Diabrotica 12-punctata)
This insect spends both its larval and adult stages on corn.
^ .-^ ^
z pi ] ; i'
. C ,, ,-i
I 1-: I^ I '.
I' '
"- s
f^ '-< -
1, ,
/1 4
r7
The adult (fig. 84, a)
feeds on the leaves in
which it makes small
holes, but it is more
common on the silk of
the young ears which
it cuts off. It may at-
tack also the tassel or
the exposed kernels of
the ears. The white,
grub-like larvae (fig.
84, c) mine the roots
of the corn. The adult
beetles are oblong and
about 11/4 inches long,
red in color, with 12
black spots on the wing covers. The insects are more abundant on
late corn than on early varieties and apparently are more common
in the western part of the State than on the peninsula.
FIG. 84.-Southern corn root-worm: a, Adult beetle,
about six times natural size; b, egg; c, larva; d,
anal segment of larva; e, work of larva at base
of corn stalk; f, pupa. (From U. S. Bur. of Ent.)
Florida Agricultural Experiment Station
CORN WEEVILS (Calandra oryzae and C. granaria)
Sweet, or field corn, which is stored, is subject to attack by
these small beetles (fig. 85) which eat the interior of the ker-
nels. As soon as weevils are noticed, the corn should be fumi-
gated with carbon bisul-
phide, using 2 or 3 pounds
to 1000 cubic feet of
space in the bin or crib.
The material is placed in
an open dish on top of
the corn and allowed to
evaporate. The fumes b
are heavier than air and
will sink, and penetrated
the corn. The bin should
be made perfectly tight
before the sulphide is in-
troduced, and kept closed
afterward for at least 24
hours. All fire and lights, FIG. 85.-Calandra granaria: a, Adult; b,
including lighted pipes, larva; c, pupa; d, Calandra oryzae. About
seven times natural size. (From U. S.
should be kept away for Bur. of Ent.)
the fumes are inflam-
mable. A safer fumigant is paradichlorobenzene. It is not inflam-
mable and is not as dangerous to human beings who breathe its
fumes. It is a new material on the market and some difficulty
may be met in obtaining it. To use, dissolve in water 12
ounces for each 100 cubic feet of space. The liquid is then
soaked up in a rag which is placed in the seed box. There is
less danger of injuring the germinating ability of the corn by
an overdose with this fumigant than with carbon bisulphide.
Even live animals, such as dogs, cats, and chickens, can be thus
fumigated safely in a box for an hour. Either of these insecti-
cides is more effective when the temperature is above 60 degrees.
OTHER CORN PESTS
Other insects attacking corn are: Sweet-potato caterpillar
(see under sweet potatoes, page 186), and serpentine leaf-miner
(see under cowpeas, page 162). The bean-jassid (see bean leaf-
hopper, page 129), lantern-fly, (see page 203), and the lesser
corn stalk-borer (see under beans, page 132) are particularly
injurious to very late-planted corn and, when the bud worm (see
Bulletin 151, Truck and Garden Insects
page 151), are the chief cause of the difficulty of growing a crop
of late-fall roasting ears in central Florida.
COWPEAS
COWPEA POD-WEEVIL, OR COWPEA CURCULIO
(Chalcodermus aeneus)
This black beetle (fig. 86, a), except in color, resembles the
cotton boll weevil and, as it often feeds on young cotton in the
early spring, it is frequently mistaken for that species. It is
an exceedingly severe pest on cowpeas. Early in the season it
feeds on the leaves of the plant, but as soon as the pods begin
to set it turns its attention to them. The females lay their eggs
in the developing seeds, making a puncture thru the pods. They
bT
,- d,
FIG. 86.-Cowpea pod-weevil: a, Adult; five times natural
size; b, larva; d, pupa. (From U. S. Bur. of Ent.)
also feed on the pods, making a feeding puncture similar to the
egg puncture. These punctures make unsightly brown spots on
pods and seeds, but the greater injury is done by the grubs
that hatch from the eggs in from 4 to 6 days. This pale yellow
larva (fig. 86, b) eats the seed. It requires a week or two to
reach full size. It then bores a hole in the side of the pod and
escapes to the ground. The adult is about 1/ inch long and has
deeply-pitted wing-covers.
Control.-Rotation of crops should be practiced. Land that
has grown a crop of heavily-infested cowpeas should not be
planted at once to a late crop of cowpeas. Neither should such
land be planted to beans. When the insects are feeding on the
leaves early in the season, they can be poisoned with lead arsen-
ate. Use 1 pound of the powder or 2 pounds of the paste to
50 gallons of water. The destruction of the early brood will
materially reduce the number attacking the pods later. On a small
garden patch or on other particularly valuable fields the insects
Florida Agricultural Experiment Station
can be collected by hand as recommended for the pumpkin bug.
PUMPKIN BUG (Nezara viridula)
This pest attacks nearly all garden plants and especially
legumes, but is particularly at home on cowpeas. The adult
insects are little more than 1/2 inch long and nearly as broad
and are usually light green in color. The young (fig. 87) are
bluish with some reddish markings. They are quite unlike the
adults in appearance. There are several generations in a year.
The adults of the last generation hibernate but not until late in
FIG. 87.-Pumpkin bug (Nezara viridula): Young. Six
times natural size. (From U. S. Bur. of Ent.)
the fall and are out early in the spring. These insects do con-
siderable damage to young plants but the most severe injury is
inflicted on the pods. Their numerous feeding punctures make
unsightly brown tough dots. They will also dwarf the pods
and if sufficiently numerous cause them to drop.
Control.-This is a difficult pest to control. Being a suck-
ing insect, arsenicals or other stomach poisons are of no avail.
The young can be killed by kerosene emulsion or a strong soap
solution, but the adults are too robust to be killed by these com-
pounds except at strengths that would be dangerous to the
plants. The only means of combating them seems to be hand-
collecting. On an ordinary field crop of cowpeas, it is ques-
tionable whether the operation would pay. It is perhaps best
Bulletin 151, Truck and Garden Insects
to plant enough for both bugs and planter and, by good cultural
methods, to keep the vines in such vigorous growing condition
that they will bear peas in spite of the bugs. In a garden, on a
particularly valuable patch of cowpeas, or on such valuable
crops as beans, tomatoes, potatoes, etc., hand-picking will pay
well. For this purpose take a pan or other wide-mouthed dish,
pour into it an inch or less of water and on this a film of
kerosene. In the early morning or on a cold rainy day when
the bugs are sluggish, walk along the rows and knock the bugs
into the pan. This is not as slow a process as it may seem at
first. An active boy can collect most of the bugs from an acre
of beans or several acres of potatoes in an hour.
The smaller but closely related Nezara hilaris does about the
same character of damage, but is comparatively rare in Florida.
SERPENTINE LEAF-MINER (Agromyza pusilla)
This is a near relative of the corn-leaf blotch-miner. (See
under corn, page 158.) Like that species, the larva works in
the central tissue of the leaf, but its burrow .- long and nar-
row, with many bends, hence the name serpentine. It is plenti-
ful in many wild plants, especially such legumes as beggarweed
and coffeeweed, and it is common in cowpeas. Its life history
is similar to that of the corn-leaf blotch-miner and may like-
wise work all winter in the southern part of the State. The
greatest damage is done to the first two leaves cotyledonss) of
very young seedlings before the true leaves are put out. Both
of these leaf-miners have numerous parasitic enemies which
generally keep them under fair control.
GARDEN FLEA-HOPPER (Halticus uhleri)
This is a minute black plant-bug (fig. 88) that attacks the
leaves of cowpeas, beggarweed, peppers, and a great variety of
d
FIG. 88.-Garden flea-hopper: a, ShoIt-winged female; b, full-winged female;
c, male; d, head of male in outline. Eight times natural size. (From U. S.
Bur. of Ent.)
Florida Agricultural Experiment Station
weeds. The attacked
spotted, "peppered"
\
FIG. 89.- (Pachymerus 4 -
maculatus): a, Adult; b,
c, egg from above and
below; d, head of ma-
ture larva. Greatly en-
larged. (From U. S. Bur.
of Ent.)
spots turn yellow, giving the plant a
appearance. The insect may be con-
trolled readily by tobacco extracts.
COWPEA SEED-WEEVILS
Two species of weevils, the four-
spotted, weevil (Pachymerus 4-macula-
ta) (fig. 89) and the Chinese weevil
(Pachymerus chinensis) (fig. 90), both
closely related to the bean-weevil
(see under beans, page 132), do about
the same character of damage to cow-
peas as their relative does to beans.
The bean-weevil also occasionally at-
tacks cowpeas and either or both of
the cowpea weevils often attack beas.
They begin their work in the field but
I I
FIG. 90.-Pachymerus chinensis: a, Adult;
b, egg; c, larva. About seven times
natural size. (From U. S. Bur. of Ent.)
it is in stored peas that they are especially injurious. These should
be fumigated or heated following directions for stored seeds. If
cowpeas are kept in cold storage at a temperature below 34 de-
grees for 2 or 3 months, the eggs, as well as weevils, are destroyed.
OTHER COWPEA PESTS
Other insects attacking cowpeas are: Wireworms (see
page 153); cutworms (see page 137); leaf-footed plant-bugs
(see page 178) ; and lesser corn stalk-borer (see page 132. The
harlequin cabbage bug (see page 148) attacks the pods.
CUCUMBERS
PICKLE WORM (Diaphania nitidalis)
Cucumbers and cantaloupes with holes bored into them
(fig. 91) are common to Florida growers, more common some
years than others. Two species of insects are responsible for
Bulletin 151, Truck and Garden Insects
this damage, the pickle worm and the melon worm. They are
closely related, very similar in appearance, and usually not dis-
tinguished by the trucker. Either or both species may be found
FIG. 91.-Injury by pickle worm to ripening cantaloupes. (From No. Car.
Agr. Exp. Sta.)
on cucumbers, melons, squashes and gourds. They differ in
their habits and consequently in methods of control.
The more common of the two is the pickle worm. This is
a whitish caterpillar with conspicuous black dots on each seg-
ment. In the early part of the season it bores into the buds,
blossoms, stems, and leaf-stalks, but as the fruits form, it con-
fines its attentions to them, always entering from the side near
the ground. In addition to the injury caused by the worm feed-
ing on the tissue of the cucumber, the entrance hole affords an
entry for various molds and other organisms of decay which
quickly spoil the cucumber.
The eggs are laid on the parts of the plant used for food
by the caterpillars. After the fruits are formed most of the
eggs are laid on the under side of them, hatching in 3 or 4 days.
The larva feeds and grows for about 2 weeks, after which time
it turns a coppery color and the black dots become less con-
spicuous. It soon pupates in a dried leaf and in about another
week the moth comes forth. This moth (fig. 92) has wings
which are clear white in the middle with a broad black border
around the margins. It measures from 1 to 11/4 inches across
the outstretched wings. This insect is commonly seen about
lights, and it may fly in the daytime.
Florida Agricultural Experiment Station
Control.-The pickle worm, because it feeds in the interior
of the buds, blossoms and fruits, cannot be reached by arsenical
sprays. The grower should carefully collect and destroy all
wormy fruit. If these wormy cucum-
bers and melons are left in the field the
caterpillars will enter fresh ones, or
complete their growth and enter the
ground to emerge as moths in a week
or two. The moth lays enough eggs
to hatch into about 300 more worms. 0 .
The best preventivemeasure against FvM2. A .-P i c k r
both of these worms is a trap crop. For size. (Original.)
this purpose plant from 4 to 8 rows of early summer crook-
necked squash for each acre of cucumbers or cantaloupes. (Fig.
93.) The large blossoms and leaves and the tender fruits of
the squash are preferred by the moths to either cucumbers or
melons, and most of the eggs will be laid on the squash. It is
better to make several plantings of the squash to provide a
FIG. 93.--Trap crop of squash for pickle and melon worms in cantaloupe
field. (From No. Car. Agr. Exp. Sta.)
succession of blossoms and fruits attractive to the moths. The
first planting should be made at the same time as that of the
cucumbers or melons, and other plantings at intervals of a week.
Bulletin 151, Truck and Garden Insects
The last planting may be placed in the hills from which the
cucumbers are missing.
The infested squash blossoms and fruit may be picked and
destroyed and if the melon worm is abundant, the vines should
be sprayed with one of the arsenicals. The quickest way to
destroy the pests on the trap crop is to pull up and burn each
lot of trap plants as soon as it has become thoroly infested and
before the worms have reached their full size. If this is neg-
lected, the trap crop is worse than useless.
Clean culture should be practiced, not only on account of
these insects, but also to keep down fungus diseases. As soon
as the grower is thru picking, the vines, fallen leaves, and other
refuse should be raked up and burned. Cucumbers or melons
should not be planted on the same land two years in succession.
MELON-WORM (Diaphania hyalinata)
In addition to boring into the cucumbers, this caterpillar
feeds extensively on the leaves of the plants attacked, which is
a habit not possessed by the pickle worm. But the melon worm
does not often bore into the vines or leaf stalks. This worm
has longitudinal stripes instead of the black dots of the pickle
worm. It never becomes coppery-colored. The moth is larger
than the other, about 13/ inches in expanse and the white area
on the wings is proportionately much larger covering all but
a narrow margin. The eggs are laid chiefly on the young leaves.
Control.-This species can be reached by arsenical sprays
because it feeds partly on the foliage. Three pounds of lead
arsenate paste should be used to 50 gallons of water; or 11/2
pounds of lead arsenate powder or of zinc arsenite powder to 50
gallons of water. Paris green may be used at the rate of 1/2
pound to 50 gallons of water, but it does not stick as well as the
others and is more likely to burn the foliage. To the 50 gallons
of insecticide should be added 3 pounds of hydrated lime, or the
milk obtained by slaking 3 pounds of fresh quick lime in warm
water. The lime is to prevent burning the foliage. If the vines
are sprayed regularly with bordeaux mixture for blight or
other fungus diseases, as they should be, the arsenical may be
placed in the bordeaux, in which case the lime is omitted.
STRIPED CUCUMBER-BEETLE (Diabrotica vittata)
This very troublesome enemy of the northern grower of
curcubits is usually entirely absent from these plants in the
peninsular part of Florida, altho it is present in the western
Florida Agricultural Experiment Station
part of the State. During the fall of 1915, however, there was
a serious outbreak in South Florida which has continued to the
present time (see An. Rep. Fla. Agr. Sta., 1915).
The adult (fig. 94, a), a yellow beetle striped with black,
measuring about 2/5 of an inch long, eats the leaves of cucum-
bers, squashes, melons, beans, watermelons, okra, and even those
of citrus trees. The slender white larvae (fig. 94, b) feed on
the roots of these plants into which they tunnel, sometimes
reaching the base of the stems. In the North the adults are
troublesome to young
attack and kill quickly
the northern practice
of covering the young
plants with cheese
cloth for a fewweeks is
not effective in Florida.
The female lays
about a hundred eggs
during her lifetime of
one month. They are
laid on the surface of
the ground where they
hatch in about a week.
In Kentucky, the larva
requires about a month
for growth and the
insect lies in the pupa,
plants only, but in South Florida they
full-grown, bearing vines. Consequently
'IX
b
d' C
d
FIG. 94.-Striped cucumber-beetle: a, Adult, six
times natural size; b, larva; c, pupa. (From
U. S. Bur. of Ent.)
which is placed just below the surface
of the ground, for a week or two. The entire life history occu-
pies but 39 days. The life history of the insect in Florida has
not been worked out, but it is probable that the life cycle is
shorter in the summer.
Control.-Probably the best method of combating the cu-
cumber-beetle in Florida is to spray the plants with lead arsen-
ate, using a pound of powder and two of lime to 50 gallons of
water. The spraying must be thoroly done so that every ex-
posed part of the plant is covered, otherwise the beetles will
collect on the unsprayed portions. (See page 203 for trap crop).
OTHER CUCUMBER PESTS
Other insects attacking cucumbers are: Melon-aphis, a
serious enemy of all curcubits (see page 199) ; cutworms (see
Bulletin 151, Truck and Garden Insects
page 137) ; thrips (see page 172) ; tarnished plant-bug (see page
149) ; and red spiders (see page 175) ; and wireworms (see page
153).
DASHEEN
This plant seems to be almost immune to insect attacks.
The writer has seen the tubers of plants growing in a very
damp place attacked by the larvae of a crane-fly (Tipula sp.)
Some of the tubers were half-eaten and in the hollows were
found empty pupa cases of the crane-flies. This damage would
not occur on well-drained soils. The larvae are legless, dirty-
white, soft-bodied, worm-like grubs. The adults are large, long-
winged, slender-bodied flies having exceedingly long and slender
legs. They are commonly seen hovering over springs or hang-
ing by their hind legs from limbs of trees or the walls of houses.
They are commonly confused with mosquitoes, especially with
the large gallinipers," but incapable of injuring man.
Dasheens are also attacked by the rotten-log caterpillar, and
quite seriously by the root-knot nematodes (see under general
garden pests, page 128).
EGGPLANT
The most destructive pests of eggplant in Florida are plant-
lice, especially the garden plant-louse (Myzus persicae). Con-
trol measures are the same as those given under cabbage, page
144.
Plant-bugs are as common on eggplant as they are on most
succulent truck crops. Their ravages are most severe in the
late fall just before the first cold weather drives them into
hibernation and when native vegetation is becoming dry and
unattractive; and also in the early spring when they first
emerge from their winter quarters. The most common of these
bugs are: Pumpkin bug (see under cowpeas, page 161); big-
footed plant-bug (see under potatoes, page 177) ; and leaf-footed
plant-bug (see under potatoes, page 178). A fourth one, the
Cotton-Stainer, may be treated here. Its name is derived from
the nature of the damage done to cotton. As a result of the
feeding of the bugs, the lint is stained yellow.
COTTON-STAINER (Dysdercus suturellus)
Like the leaf-footed plant-bug this insect is occasionally
injurious to citrus fruits, but neither is as common in groves
as the pumpkin bug. The cotton-stainer has a marked tendency
Bulletin 151, Truck and Garden Insects
page 137) ; thrips (see page 172) ; tarnished plant-bug (see page
149) ; and red spiders (see page 175) ; and wireworms (see page
153).
DASHEEN
This plant seems to be almost immune to insect attacks.
The writer has seen the tubers of plants growing in a very
damp place attacked by the larvae of a crane-fly (Tipula sp.)
Some of the tubers were half-eaten and in the hollows were
found empty pupa cases of the crane-flies. This damage would
not occur on well-drained soils. The larvae are legless, dirty-
white, soft-bodied, worm-like grubs. The adults are large, long-
winged, slender-bodied flies having exceedingly long and slender
legs. They are commonly seen hovering over springs or hang-
ing by their hind legs from limbs of trees or the walls of houses.
They are commonly confused with mosquitoes, especially with
the large gallinipers," but incapable of injuring man.
Dasheens are also attacked by the rotten-log caterpillar, and
quite seriously by the root-knot nematodes (see under general
garden pests, page 128).
EGGPLANT
The most destructive pests of eggplant in Florida are plant-
lice, especially the garden plant-louse (Myzus persicae). Con-
trol measures are the same as those given under cabbage, page
144.
Plant-bugs are as common on eggplant as they are on most
succulent truck crops. Their ravages are most severe in the
late fall just before the first cold weather drives them into
hibernation and when native vegetation is becoming dry and
unattractive; and also in the early spring when they first
emerge from their winter quarters. The most common of these
bugs are: Pumpkin bug (see under cowpeas, page 161); big-
footed plant-bug (see under potatoes, page 177) ; and leaf-footed
plant-bug (see under potatoes, page 178). A fourth one, the
Cotton-Stainer, may be treated here. Its name is derived from
the nature of the damage done to cotton. As a result of the
feeding of the bugs, the lint is stained yellow.
COTTON-STAINER (Dysdercus suturellus)
Like the leaf-footed plant-bug this insect is occasionally
injurious to citrus fruits, but neither is as common in groves
as the pumpkin bug. The cotton-stainer has a marked tendency
Florida Agricultural Experiment Station
to be gregarious. Altho it is usually entirely absent from groves,
truck, and cotton fields, it sometimes occurs in large numbers
and does much damage.
The cotton-stainer, like the other plant bugs, injures
plants with its sucking beak. When a puncture is made in
the fruit of an eggplant, a hard, brown spot develops and if
the fruit is young it will probably be deformed. If punc-
tures are numerous the fruit turns yellow and falls off. But
the chief damage is done to the stem of the young plant.
The adult is a dull red bug about a half inch long and
oblong ovate in shape. The young is similar in color and
shape, but is smaller and lacks wings.
Like the other large plant-bugs, the young of the cotton-
stainer can be killed by strong contact insecticides (see pump-
kin bug under cowpeas, page 161), but in the adult stage it
is better to collect them. The cotton-stainers are very fond
of cottonseed meal and advantage may be taken of this to
trap them. Small piles of the meal are placed about in the
field. As the bugs gather, the piles are from time to time
sprayed with pure kerosene or a strong emulsion of kerosene
and water. The Spanish cocklebur (Urena lobata) is one of
the favorite host plants of this insect and should be destroyed
when growing about the edges of truck patches.
GRAY STINKBUG (Pentatonma punctipes)
This bug is commonly associated with the other large
plant-bugs on eggplant and other plants. It has the general
shape of the pumpkin bug but is only half as large and is
grayish-brown instead of green in color. The nature of the
damage and the control measures are identical with those of
the pumpkin bug (see under cowpeas, page 161).
OTHER EGGPLANT PESTS
Other insects attacking eggplant are: Flea-beetles (see
under beets, page 136) ; harlequin cabbage-bug (see under cab-
bage, page 148) ; serpentine leaf-miner (see under cowpeas, page
162); and red spiders (see under peas, page 175). For still
other eggplant pests, see page 203.
LETTUCE
The cabbage looper (see under cabbage, page 140) is the
most troublesome insect enemy of winter-grown lettuce. A sin-
gle larva may eat out the bud and destroy the value of a plant
altho not killing it outright.
Bulletin 151, Truck and Garden Insects
Aphids are very commonly present on lettuce. The most
common species is the garden aphid but occasionally a large
red aphid (Macrosiphon rudbeckiae) is found. For remedies
see cabbage plant-lice, page 144.
LEAF-HOPPERS
The bean Empoasca mali and other leaf-hoppers are quite
common on lettuce even during the coldest months. In addi-
tion to sucking the sap of the plants these insects, and also
flies which breed in the decaying heads of lettuce, spread sev-
eral destructive fungus diseases of lettuce. These diseases are
usually much more serious to winter-grown lettuce than the
direct attacks of insects. Whether the hopperdozer (see bean
leaf-hopper, page 129) could be used successfully on lettuce is a
question. When spraying lettuce with bordeaux for fungus dis-
eases it would be well to add tobacco to kill the leaf-hoppers.
During the winter the field will not be as quickly reinfested
from surrounding fields as would a field of beans in the fall.
All dead and diseased lettuce should be removed from the field
at once. This will not only lessen the amount of spores to
spread contagion, but will also stop the breeding of the flies.
OTHER LETTUCE PESTS
Other insects attacking lettuce are: Tarnished plant-bug
(see under celery, page 149) ; cutworms (see under cabbage,
page 137) ; and the pitted lygaeid (see page 204).
MELONS
The insects attacking this crop are the same as those dis-
cussed under cucumbers (see page 163), and watermelons (see
page 199).
MUSTARD
The insects attacking this crop are the same as those dis-
cussed under cabbage (see page 137).
OKRA
The chief insect enemies of okra are: Flea-beetles (see
under beets, page 136); the garden aphid (see plant-lice under
cabbage, page 144); red spiders (see under peas, page 175);
cutworms (see under cabbage, page 137); pumpkin bugs (see
under cowpeas, page 161) ; striped cucumber-beetle (see under
cucumbers, page 166) ; and whitefly (see under sweet potatoes,
page 187). Others are discussed here.
Bulletin 151, Truck and Garden Insects
Aphids are very commonly present on lettuce. The most
common species is the garden aphid but occasionally a large
red aphid (Macrosiphon rudbeckiae) is found. For remedies
see cabbage plant-lice, page 144.
LEAF-HOPPERS
The bean Empoasca mali and other leaf-hoppers are quite
common on lettuce even during the coldest months. In addi-
tion to sucking the sap of the plants these insects, and also
flies which breed in the decaying heads of lettuce, spread sev-
eral destructive fungus diseases of lettuce. These diseases are
usually much more serious to winter-grown lettuce than the
direct attacks of insects. Whether the hopperdozer (see bean
leaf-hopper, page 129) could be used successfully on lettuce is a
question. When spraying lettuce with bordeaux for fungus dis-
eases it would be well to add tobacco to kill the leaf-hoppers.
During the winter the field will not be as quickly reinfested
from surrounding fields as would a field of beans in the fall.
All dead and diseased lettuce should be removed from the field
at once. This will not only lessen the amount of spores to
spread contagion, but will also stop the breeding of the flies.
OTHER LETTUCE PESTS
Other insects attacking lettuce are: Tarnished plant-bug
(see under celery, page 149) ; cutworms (see under cabbage,
page 137) ; and the pitted lygaeid (see page 204).
MELONS
The insects attacking this crop are the same as those dis-
cussed under cucumbers (see page 163), and watermelons (see
page 199).
MUSTARD
The insects attacking this crop are the same as those dis-
cussed under cabbage (see page 137).
OKRA
The chief insect enemies of okra are: Flea-beetles (see
under beets, page 136); the garden aphid (see plant-lice under
cabbage, page 144); red spiders (see under peas, page 175);
cutworms (see under cabbage, page 137); pumpkin bugs (see
under cowpeas, page 161) ; striped cucumber-beetle (see under
cucumbers, page 166) ; and whitefly (see under sweet potatoes,
page 187). Others are discussed here.
Bulletin 151, Truck and Garden Insects
Aphids are very commonly present on lettuce. The most
common species is the garden aphid but occasionally a large
red aphid (Macrosiphon rudbeckiae) is found. For remedies
see cabbage plant-lice, page 144.
LEAF-HOPPERS
The bean Empoasca mali and other leaf-hoppers are quite
common on lettuce even during the coldest months. In addi-
tion to sucking the sap of the plants these insects, and also
flies which breed in the decaying heads of lettuce, spread sev-
eral destructive fungus diseases of lettuce. These diseases are
usually much more serious to winter-grown lettuce than the
direct attacks of insects. Whether the hopperdozer (see bean
leaf-hopper, page 129) could be used successfully on lettuce is a
question. When spraying lettuce with bordeaux for fungus dis-
eases it would be well to add tobacco to kill the leaf-hoppers.
During the winter the field will not be as quickly reinfested
from surrounding fields as would a field of beans in the fall.
All dead and diseased lettuce should be removed from the field
at once. This will not only lessen the amount of spores to
spread contagion, but will also stop the breeding of the flies.
OTHER LETTUCE PESTS
Other insects attacking lettuce are: Tarnished plant-bug
(see under celery, page 149) ; cutworms (see under cabbage,
page 137) ; and the pitted lygaeid (see page 204).
MELONS
The insects attacking this crop are the same as those dis-
cussed under cucumbers (see page 163), and watermelons (see
page 199).
MUSTARD
The insects attacking this crop are the same as those dis-
cussed under cabbage (see page 137).
OKRA
The chief insect enemies of okra are: Flea-beetles (see
under beets, page 136); the garden aphid (see plant-lice under
cabbage, page 144); red spiders (see under peas, page 175);
cutworms (see under cabbage, page 137); pumpkin bugs (see
under cowpeas, page 161) ; striped cucumber-beetle (see under
cucumbers, page 166) ; and whitefly (see under sweet potatoes,
page 187). Others are discussed here.
Florida Agricultural Experiment Station.
OKRA CATERPILLAR, OR ABUTILON MOTH (Cosmophila erosa)
Okra leaves are often eaten by a light-green caterpillar
(fig. 95) which has no conspicuous markings. (The moth, fig.
96.) Like the cabbage looper, this insect is a semi-looper. It
grows to a length of 1%8 inches
and then rolls up the edge of the
leaf and pupates in the fold.
According to H. L. Dozier of the
department of entomology, Flor-
ida Agricultural Experiment Sta-
tion, who has worked out the life
history, it spends from 5 to 6
days in the pupa. The egg hatches
in from 3 to 4 days and the
larva requires about 24 days for
growth, making a generation re-
FIG. 95.-Okra caterpillar: Larva. quire about 34 days.
Natural size. (Original.) The caterpillar is attacked
by a little wasp-like parasitic insect (Chalcis ovata) which pre-
vents it from becoming a greater pest. The caterpillar is easily
FIG. 96.-Okra caterpil-
lar: a, Adult male; b,
adult female. Natural
size. (Original.)
controlled by lead arsen-
ate. The sprayed pods
should be thoroly washed
before they are cooked.
CORN EAR-WORM
The corn ear-worm
.., attacks the pods of okra
much as it does cotton
FIG. 97.-Corn ear-worm on tobacco buds. bolls, or seed-pods of to-
About natural size. (Fla. Agr. Exp. Sta. bacco (fig. 97), that is, it
Bul. 48.)
Bulletin 151, Truck and Garden Insects
bores into the pods and feeds on the interior. Control meas-
ures are the same as those used against this insect on toma-
toes, page 189.
COTTON SQUARE-BORER (Uranotes mellinus)
This butterfly, called the gray hair-streak," deposits eggs
on okra. The larvae, a green caterpillar, eats the leaves and
bores into the buds. The purplish butterfly has a small narrow
tail-like appendage projecting from its hind wings. It is this
appendage that suggests the name of "hair-streak." The but-
terfly measures about 21/ inches across the wings. Besides
attacking cotton, where it mines into the squares, the caterpil-
lar attacks loquats, where it mines into the blossom buds. (See
An. Rep. Fla. Agr. Exp. Sta., 1913, page ixx.)
ONIONS
ONION THRIPS (Thrips tabaci, Lind)
These thrips (fig. 98) are responsible for the blanching
and withering of the tips of onion leaves. They are always
present in onion fields in Florida, working thruout the year,
except during the cold-
est days of winter.
Like other thrips, they
are always more abun-
dant in continued dry
weather, and compar-
atively scarce after a
prolonged rainy pe-
riod. They are deli-
cate insects, about
1/25 of an inch long,
and are knocked off
the plants and killed
by heavy rains.
Thrips belong to the
sucking class of in-
i sects. Their punctures
FIG. 98.-Onion thrips (Thrips tabaci). Greatly are not deep but are
magnified. (Fla. Agr. Exp. Sta. Bul. 46.)
very numerous so
that the plant tissue, when the fresh wound is examined, has
the appearance of having been rasped. Later, the tip of the
leaf whitens and shrivels. This continuous killing of leaves
greatly interferes with the growth of the onions, and control
Florida Agricultural Experiment Station
measures used will repay their cost many times over. This in-
sect attacks cabbage, cauliflower, tobacco and many other plants
(see Fla. Agr. Exp. Sta. Bul. 26, p. 105) but is most serious
on onions.
Eggs are placed singly in the leaf tissue just below its sur-
face. They hatch in about 4 days. The larval stages last from
7 to 9 days, the insect molting twice. Then follows the nymphal
stage during which the insect is dormant and takes no food.
The wings show for the first time during this stage which lasts
4 days.
The insects are easily killed by whale-oil soap, 1 pound to
4 gallons of water, or by any of the tobacco extracts recom-
mended for the flower thrips. A half-pint of black leaf 40 and
3 or 4 pounds of soap to 50 gallons of water is a sufficient and
economical spray. It may be necessary to spray twice in order
to get the nymphs that are hidden in the bases of the leaves or
elsewhere at the time of the first spraying.
ONION ROOT-MAGGOT (Phorbia fusciceps)
The onion root-maggot (see fig. 75) begins its depreda-
tions early in the season on the young and tender onion plants.
" The eggs are deposited loosely above the surface of the ground
on the stem and basal leaves. Usually 5 or 6 eggs are deposited
on the plant. In about a week these eggs hatch and the young
maggots burrow downward within the leaf sheath, leaving dis-
colored streaks to mark their passage; penetrating the soft cylin-
drical root, they greedily devour the interior, leaving the outer
skin. Having consumed one plant, it is abandoned and another
is attacked. About 2 weeks is required for the maggot to com-
plete its growth, when it usually leaves the onion and, retiring
into the neighboring soil, forms the pupa, from which it
emerges as an adult fly in about a fortnight. The winter is
probably passed in the pupa state in the ground." (Fla. Agr.
Exp. Sta. Bul. 34, p. 306.) Pegomya cepetorum, the Northern
imported onion maggot, is not known to occur in Florida.
Control.-The maggots in the bulbs are out of reach of any
insecticides and all efforts must be aimed at preventing them
from reaching the plants. As many of the eggs are deposited
on the ground near the plants, or are loosely attached, frequent
cultivation will break many of them and remove others to such
a distance that the newly-hatched maggots will fail to reach
the plants.
Onions should not be planted on land that has had a crop
Bulletin 151, Truck and Garden Insects
of cabbage, cauliflower, collards, turnips, mustard, and other
plants of this family during the summer or early fall. All
wild crucifers in or near the field should be destroyed. In an
infested field of onions or cabbages all refuse of the crop should
be pulled and burned as soon as the crop is harvested.
Several of the Northern stations report success in poison-
ing the flies of the onion root-maggot before they have had op-
portunity to lay many eggs. The following poisoned bait was
prescribed by the Wisconsin Station. Five grams of sodium
arsenite are dissolved in a gallon of boiling water and a pint of
cheap molasses added. This solution is sprayed on the plants
with a coarse nozzle so that it will fall in large drops. It must
be renewed after every heavy rain or once a week in dry
weather. Another method is to distribute the poison in from
15 to 20 small pans for each acre of onions. These need to be
renewed only after heavy rains or when dried out. During the
dry weather of the average spring this method would probably
be more economical than spraying.
OTHER ONION PESTS
Other insects attacking onions are: Fall army worm (see
under corn, page 155) ; wireworms (see under corn, page 153);
and cutworms (see under cabbage, page 137).
PARSLEY
Two insects attack this crop quite commonly in Florida.
They are: Celery worm (see celery caterpillar, page 150), and
cutworms (see under cabbage, page 137).
PEAS
Peas, or English peas, also sometimes called garden peas,
are attacked by about the same pests as the sweet, or flowering,
peas. Their pests are discussed here. Cowpeas, or field peas,
are sometimes called peas. Their pests are discussed under the
heading of cowpeas in an earlier part of this bulletin.
PEA-APHID (Macrosiphum pisi)
This green plant-louse is much larger than the garden
aphid, measuring 3/16 of an inch long. They collect on the
young and tender portions of the vines near the growing tip
which they may cover completely. They commonly collect also
in the bud where they are concealed by the bracts.
Bulletin 151, Truck and Garden Insects
of cabbage, cauliflower, collards, turnips, mustard, and other
plants of this family during the summer or early fall. All
wild crucifers in or near the field should be destroyed. In an
infested field of onions or cabbages all refuse of the crop should
be pulled and burned as soon as the crop is harvested.
Several of the Northern stations report success in poison-
ing the flies of the onion root-maggot before they have had op-
portunity to lay many eggs. The following poisoned bait was
prescribed by the Wisconsin Station. Five grams of sodium
arsenite are dissolved in a gallon of boiling water and a pint of
cheap molasses added. This solution is sprayed on the plants
with a coarse nozzle so that it will fall in large drops. It must
be renewed after every heavy rain or once a week in dry
weather. Another method is to distribute the poison in from
15 to 20 small pans for each acre of onions. These need to be
renewed only after heavy rains or when dried out. During the
dry weather of the average spring this method would probably
be more economical than spraying.
OTHER ONION PESTS
Other insects attacking onions are: Fall army worm (see
under corn, page 155) ; wireworms (see under corn, page 153);
and cutworms (see under cabbage, page 137).
PARSLEY
Two insects attack this crop quite commonly in Florida.
They are: Celery worm (see celery caterpillar, page 150), and
cutworms (see under cabbage, page 137).
PEAS
Peas, or English peas, also sometimes called garden peas,
are attacked by about the same pests as the sweet, or flowering,
peas. Their pests are discussed here. Cowpeas, or field peas,
are sometimes called peas. Their pests are discussed under the
heading of cowpeas in an earlier part of this bulletin.
PEA-APHID (Macrosiphum pisi)
This green plant-louse is much larger than the garden
aphid, measuring 3/16 of an inch long. They collect on the
young and tender portions of the vines near the growing tip
which they may cover completely. They commonly collect also
in the bud where they are concealed by the bracts.
Florida Agricultural Experiment Station
There are usually a few of these insects on peas and as the
hot dry weather of spring comes on they multiply so rapidly
that they kill the vines in a few days.
The life history and remedies are so similar to those of
the garden aphid (see cabbage plant-lice, page 144), which also
is common on peas, as to need no restatement. The lice in the
bud have better protection than those on cabbages and it is
necessary to use strong pressure in order to force the buds open
so that the liquids can reach the aphids.
RED SPIDERS
Another pest that becomes a serious menace to peas in dry
spring weather is the mite Tetranychus telerius. Either the
spider or the aphid or both usually destroy the late winter-
planted crop of peas.
Peas when attacked become dry, mealy or cobwebby" in
appearance, cease to grow, wilt down and soon die. So rapidly
does an infestation develop that in a few days from the time
damage is first noticed the vines are dead.
This pest is not a true insect but belongs to the spider
class of animals and to a subdivision distinct from the large
garden spiders, being more closely related to red bugs."
Members of this group are often called spider mites" and
also spinning mites from the habit many of them have of
spinning a silken web over the host plant or a part of it.
" Spinning mites" would be the most nearly correct popular
name. The name red spider is misapplied as these pests are not
true spiders and are not usually red; they are often yellow and
sometimes green.
The red spiders are usually round in outline, small, and
have eight legs when full grown. This characteristic at once
serves to distinguish spiders from insects, which never have
more than six legs.
Altho they are troublesome out of doors only in dry
weather, they may be troublesome thruout the year in green-
houses, on house plants and in other places sheltered from rain.
Life History.-The egg hatches in from 3 to 5 days. The
young mites require about 10 days during warm weather for
growth and the adults are about 4 days old before they begin
to lay eggs. Between 2 and 3 weeks is the time usually re-
quired for a generation but it has been found to be as few as
10 days and as many as 35.
These mites spin irregular strands of silk all over the host
Bulletin 151, Truck and Garden Insects
plant so that a severely-infested plant is well-webbed. They
use this web as a road over which to travel, but it also serves
to hold the eggs to the leaves and perhaps tends to lessen the
danger of the mites being washed off by heavy rains. They
spread by crawling from place to place, altho they may be
carried by the wind.
They damage the plant by sucking the sap from the leaves.
Each puncture is extremely minute but in the case of a severe
infestation the plant becomes white, the chlorophyll or green
coloring matter being removed with the sap.
Control.-As these mites are dry weather creatures, one of
the most effective means of control is frequent and heavy
sprinkling, especially if strong pressure can be had. A field
supplied with the common system of overhead irrigation also
supplies a fairly satisfactory means of control. A stream of
water not only knocks off many of the mites, but the moisture
aids their numerous enemies.
If sprinkling systems are not available recourse must be
had to insecticides. The best are those containing sulphur in
some form. Free sulphur or some of its compounds may be
used, applying it either dry, or in the form of a spray. Free
sulphur is one of the best remedies for red spiders or mites. It
is somewhat slower in its action than some compounds of sul-
phur, taking often 2 or 3 days or more to do its work, but it
remains active for a long time, frequently 2 or 3 weeks, and
usually kills the mites. Sulphur can be applied dry, and driven
into the vines by hand, or shaken into the vines thru a closely
woven cloth or a perforated can.
It is better to mix 3 parts of dry sulphur with 1 pound of
hydrated lime. The lime can be bought or made by adding 32
pounds (4 gallons) of water to each 100 pounds of quicklime.
Mix hydrated lime and sulphur thoroly. The best results will
be obtained by applying the dust at night or in the early morn-
ing when the air is quiet and the plants are wet with dew, as
the dust sticks better then. It works better when the nights
are moist and the days bright and sunny, for under these con-
ditions the oxidation of the sulphur takes place more rapidly.
As a spray from 1 to 5 pounds of sulphur to 50 gallons of
water can be used.
Whether the grower can use the dust or the spray most
economically will depend on a number of things, such as the
outfit that he can obtain, the distance the water must be hauled,
Florida Agricultural Experiment Station
and the severity of the infestation, the spray being a little
quicker in its action, particularly in unfavorable weather, than
the dust.
Of the compounds of sulphur, lime-sulphur is one of the
best. Use about 1 gallon to 70 gallons of water. Use either
the commercial product, or mix 8 pounds of lime and 8 pounds
of sulphur. Cover the lime with about 6 quarts of water, and
as the mixture becomes heated, add the sulphur slowly. When
the slaking is over, quickly cool the mass by pouring cold water
into it.
A compound that will act quickly and can usually be bought
at drug stores is potassium sulphide (liver of sulphur). One
pound of this to 50 gal-
B lons of water will prove
Satisfactory, especially if
from 2 to 5 pounds of
Y fflour are added.
PEA-WEEVIL
(Laria pisorum)
This weevil (fig. 132)
t works in dried peas in
FId. 99.-Pea-weevil (Laria pisorum): b, the same manner that
Adult; c, full-grown larva; d, pupa; g, pea
showing exit hole, natural size. Much en- the bean-weevil works in
large. (From U. S. Bur. of Ent.)
beans. It is closely re-
lated to that species and the treatment of infested seeds is the
same. (See bean-weevil, page 132.)
Other pests of peas are: Onion root-maggot (see under
onions, page 173) ; and plant-bugs (see under potatoes, page 177,
and pumpkin bug under cowpeas, page 161). The bugs attack
chiefly the young pods.
PEPPER
The insect pests common to the pepper are: Garden aphid
(see plant-lice, page 144) ; flea-beetles (see page 136) ; pumpkin-
bug (see page 161); leaf-footed plant-bug (see page 178); flea-
hopper (see page 162) ; and blister beetles (see page 134).
POTATOES
BIG-FOOTED PLANT-BUG (Acanthocephala femorata)
This big brown bug (fig. 100) with club-shaped leg-joints is
quite common on early potatoes especially when planted near
hammocks, in which they hibernate. It is by far the -largest
Florida Agricultural Experiment Station
and the severity of the infestation, the spray being a little
quicker in its action, particularly in unfavorable weather, than
the dust.
Of the compounds of sulphur, lime-sulphur is one of the
best. Use about 1 gallon to 70 gallons of water. Use either
the commercial product, or mix 8 pounds of lime and 8 pounds
of sulphur. Cover the lime with about 6 quarts of water, and
as the mixture becomes heated, add the sulphur slowly. When
the slaking is over, quickly cool the mass by pouring cold water
into it.
A compound that will act quickly and can usually be bought
at drug stores is potassium sulphide (liver of sulphur). One
pound of this to 50 gal-
B lons of water will prove
Satisfactory, especially if
from 2 to 5 pounds of
Y fflour are added.
PEA-WEEVIL
(Laria pisorum)
This weevil (fig. 132)
t works in dried peas in
FId. 99.-Pea-weevil (Laria pisorum): b, the same manner that
Adult; c, full-grown larva; d, pupa; g, pea
showing exit hole, natural size. Much en- the bean-weevil works in
large. (From U. S. Bur. of Ent.)
beans. It is closely re-
lated to that species and the treatment of infested seeds is the
same. (See bean-weevil, page 132.)
Other pests of peas are: Onion root-maggot (see under
onions, page 173) ; and plant-bugs (see under potatoes, page 177,
and pumpkin bug under cowpeas, page 161). The bugs attack
chiefly the young pods.
PEPPER
The insect pests common to the pepper are: Garden aphid
(see plant-lice, page 144) ; flea-beetles (see page 136) ; pumpkin-
bug (see page 161); leaf-footed plant-bug (see page 178); flea-
hopper (see page 162) ; and blister beetles (see page 134).
POTATOES
BIG-FOOTED PLANT-BUG (Acanthocephala femorata)
This big brown bug (fig. 100) with club-shaped leg-joints is
quite common on early potatoes especially when planted near
hammocks, in which they hibernate. It is by far the -largest
Bulletin 151, Truck and Garden Insects
plant-bug in Florida, being more than an inch long. Like the
other plant-bugs, these use for food the juices of succulent,
quickly-growing plants. The potato is a
favorite. It is not only very succulent, but
its large stems furnish sufficient support
for these heavy bugs. The insects usually
settle 3 or 4 inches below the top and the
withdrawal of sap causes the tip of the
plant to wilt, markedly. If the attack is
persistent the top will die. It is probable
that the damage this bug, as well as the
other plant-bugs, inflicts is not due entirely
Fia. 100.-Big-footed to the loss of sap. They may inject a
plant-bug. Natural poison into the puncture.
size. (Original.)
Control.-These insects are so large
and their effects on the plant so conspicuous that collecting by
hand is an easy matter. The wilted tops show the location of
thebugs. Twoor three collections during the season usuallysuffice.
This bug is particularly abundant in the early spring on
thistles. These weeds should be cut down when around the
margin of truck fields. For a trap crop see page 205.
LEAF-FOOTED PLANT-BUG (Leptoglossus phyllopus)
This bug attacks the great majority of truck and garden
crops, but potatoes, beans, cowpeas, and tomatoes are favorites.
It is not as large as the big-footed
plant-bug, but makes up in numbers
what it lacks in size. Next to the
pumpkin bug it is the most common of
the larger plant-bugs. It also attacks
citrus. It is readily recognized bythe yel-
low line running across the wing covers
and the peculiar expansion of its hind
tibiae which suggest its name (fig. 101).
Control measures are the same as
those for the pumpkin bug (see under
cowpeas, page 161).
MAY-BEETLES, OR WHITE GRUBS
(Lachnosterna sp.) FIG. 101.-Leaf-footed plant-
These large fleshy-white grubs (fig. br Epar. gd. rBlom F1a.
102) which are so injurious to grass
lands do some damage to potatoes when planted on land that
was previously in grass by eating the tubers. They do not
Florida Agricultural Experiment Station
usually eat more than half of the potato, hollowing it out on
one side. They seldom eat the main stem of the plant. These
grubs are a fa-
vorite food of
moles which in
tunneling the
ground for the
grubs, do more
damage to the
potato t han do e a b
t e grubs. By FG. 102.-May-beetle or June-bug (Lachnosterna arou-
grubs. y ata): a, Adult; b, pupa; c, egg; d, young grub; 6,
ridding his fields full-grown grub. Natural size. (From U. S. Bur.
of white grubs
the farmer will greatly lessen the number of moles. Moles do
not, as is commonly supposed, feed on vegetable matter but
break off the roots and subterranean stems of plants in their
search for insects.
White grubs are slow-growing and very long-lived. All
spend many months in the larval stage, some spending 3 years.
When full-grown the grubs form pupae (fig. 102, b) in
earthen cells in the ground. The adults (fig. 102, a) are the
well-known "June-bugs" or "May-beetles" which are so
abundant about lights. Like the cutworms, the white grubs
are active thruout the year in Florida.
Control.-The only practical control measure is to rid the
ground of the grubs as thoroly as possible before the crop is
planted. This is best done when the ground is plowed. En-
courage chickens and turkeys and such wild birds as crows and
grackles to follow the plow, or turn pigs into the field. It is
particularly important to take these precautions if there has
been much grass on the land. Skunks are persistent enemies
of white grubs as well as other insects and should be protected
by the farmers.
The large Carrot-beetle (Ligyrus gibbosus) does about the
same damage as white grubs, has a similar life history and
calls for identical control measures.
COLORADO POTATO-BEETLE (Leptinotarsa decemlineata)
This notorious pest of the Northern potato grower fortun-
ately has not yet made its appearance in the main potato-grow-
ing sections of our State. This beetle is present in the northern
counties of Florida. The infected area is spreading slowly but
Bulletin 151, Truck and Garden Insects
the beetle probably never will be as severe a pest to the main
crop in Florida as it is to the Northern crop, because the insect
is in hibernation during most of the period when the winter
potatoes are growing. In the northern and western parts of
the State, during the summer when there are no potatoes, it
feeds on tomatoes and wild species of Solanum. The latter
should be destroyed if found near potato fields in those parts of
the State.
The insect is easily controlled by lead arsenate. When po-
tatoes are regularly sprayed with bordeaux, as they should be
as a precaution against blight, the lead arsenate can be added
to that solution.
OTHER POTATO PESTS
Other insects attacking potatoes are: Flea-beetles (see
under beets, page 136) ; plant-lice (see under cabbage, page 144) ;
pumpkin bugs (see under cowpeas, page 161) ; blister-beetles
(see under beets, page 134) ; and mealy bugs (see page 205).
RADISHES
The insects commonly attacking radishes are: Garden aphid
(see plant-lice under cabbage, page 144) ; cabbage root-maggot
(see under cabbage, page 146) ; and flea-beetles (see under beets,
page 136).
ROSELLE
The chief insect pest of this crop are the okra caterpillar
(see page 171), and the corn earworms (see page 151).
SQUASH
VINE BORER (Melittia satyriniformis)
The larva of this moth mines into the interior of the vine
and causes it to wilt and finally to die. The grub (fig. 103, d) is
whitish in color, somewhat flattened, and is about an inch long.
After completing its growth, the larva leaves the plant and en-
ters the ground to pupate. The adult, a moth (fig. 103, a),
measures 11/4 inches across the wings. It is an attractive in-
sect with its hind-wings transparent in the centers and mar-
gined with brown; fore-wings olive-brown, olive-green thorax,
and orange abdomen. The eggs are laid on the vines near the
ground, hatch in 7 days and the grub at once bores into the
stem of the plant.
Bulletin 151, Truck and Garden Insects
the beetle probably never will be as severe a pest to the main
crop in Florida as it is to the Northern crop, because the insect
is in hibernation during most of the period when the winter
potatoes are growing. In the northern and western parts of
the State, during the summer when there are no potatoes, it
feeds on tomatoes and wild species of Solanum. The latter
should be destroyed if found near potato fields in those parts of
the State.
The insect is easily controlled by lead arsenate. When po-
tatoes are regularly sprayed with bordeaux, as they should be
as a precaution against blight, the lead arsenate can be added
to that solution.
OTHER POTATO PESTS
Other insects attacking potatoes are: Flea-beetles (see
under beets, page 136) ; plant-lice (see under cabbage, page 144) ;
pumpkin bugs (see under cowpeas, page 161) ; blister-beetles
(see under beets, page 134) ; and mealy bugs (see page 205).
RADISHES
The insects commonly attacking radishes are: Garden aphid
(see plant-lice under cabbage, page 144) ; cabbage root-maggot
(see under cabbage, page 146) ; and flea-beetles (see under beets,
page 136).
ROSELLE
The chief insect pest of this crop are the okra caterpillar
(see page 171), and the corn earworms (see page 151).
SQUASH
VINE BORER (Melittia satyriniformis)
The larva of this moth mines into the interior of the vine
and causes it to wilt and finally to die. The grub (fig. 103, d) is
whitish in color, somewhat flattened, and is about an inch long.
After completing its growth, the larva leaves the plant and en-
ters the ground to pupate. The adult, a moth (fig. 103, a),
measures 11/4 inches across the wings. It is an attractive in-
sect with its hind-wings transparent in the centers and mar-
gined with brown; fore-wings olive-brown, olive-green thorax,
and orange abdomen. The eggs are laid on the vines near the
ground, hatch in 7 days and the grub at once bores into the
stem of the plant.
Bulletin 151, Truck and Garden Insects
the beetle probably never will be as severe a pest to the main
crop in Florida as it is to the Northern crop, because the insect
is in hibernation during most of the period when the winter
potatoes are growing. In the northern and western parts of
the State, during the summer when there are no potatoes, it
feeds on tomatoes and wild species of Solanum. The latter
should be destroyed if found near potato fields in those parts of
the State.
The insect is easily controlled by lead arsenate. When po-
tatoes are regularly sprayed with bordeaux, as they should be
as a precaution against blight, the lead arsenate can be added
to that solution.
OTHER POTATO PESTS
Other insects attacking potatoes are: Flea-beetles (see
under beets, page 136) ; plant-lice (see under cabbage, page 144) ;
pumpkin bugs (see under cowpeas, page 161) ; blister-beetles
(see under beets, page 134) ; and mealy bugs (see page 205).
RADISHES
The insects commonly attacking radishes are: Garden aphid
(see plant-lice under cabbage, page 144) ; cabbage root-maggot
(see under cabbage, page 146) ; and flea-beetles (see under beets,
page 136).
ROSELLE
The chief insect pest of this crop are the okra caterpillar
(see page 171), and the corn earworms (see page 151).
SQUASH
VINE BORER (Melittia satyriniformis)
The larva of this moth mines into the interior of the vine
and causes it to wilt and finally to die. The grub (fig. 103, d) is
whitish in color, somewhat flattened, and is about an inch long.
After completing its growth, the larva leaves the plant and en-
ters the ground to pupate. The adult, a moth (fig. 103, a),
measures 11/4 inches across the wings. It is an attractive in-
sect with its hind-wings transparent in the centers and mar-
gined with brown; fore-wings olive-brown, olive-green thorax,
and orange abdomen. The eggs are laid on the vines near the
ground, hatch in 7 days and the grub at once bores into the
stem of the plant.
Florida Agricultural Experiment Station
A wilted vine
S should be inves-
tigated and if the
entrance hole
made by the
worm, about
which there is
b usually alitt 1 e
u fras, is found the
e vine should be
= cut open and the
d I worm removed.
FIG. 103.-Squash-vine borer: a, Adult: b, adult with Be ure cut the
wings folded; c, eggs on stalk; d, larva at work; e,t t
pupa; f, cocoon. One-third larger than natural size. stem only length-
(From U. S. Bur. of Ent.)
wise and never
across the fibers and the vine probably will recover. To induce
i to take root beyond the injury, cover the vine with dirt.
SQUASH-BUG (Anasa tristis)
These squash-bugs (fig. 104) are large brownish-black, ob-
long bugs, somewhat over a half inch long, which frequent in
groups the under sides of the stems of squashes, suck the sap,
cause the plants to wilt and perhaps die. They are shy crea-
tures and when approached move to the other side of the stem
out of sight. They are not nearly so destructive to squashes in
Florida as in more northern states, perhaps because they do
riot become active in the spring until the main crop of squashes
is too nearly mature to be seriously damaged. The adults are
common in summer, feeding on various wild plants.
The eggs are laid in bunches on the under side of the
leaves and commonly in the angles formed by the larger veins.
They are brownish in color and quite conspicuous. The newly-
hatched nymph (fig. 104) is oval with yellow abdomen, black
thorax, and pink feelers (antennae). After the first molting
the nymphs become black with gray thorax.
Hand picking is about the only practical
method of control, altho the young may be
killed by tobacco sprays. The egg masses
should -also be picked off or crushed.
OTHER SQUASH PESTS
FIa. 104.-Squash-bug:
Other insects attacking the squash are: Young nymphs and
om adult. Natural size.
Pickle worm and melon worm (see under (From U. S. Bur. of
Ent.) 7
Bulletin 151, Truck and Garden Insects
cucumbers, pages 163 and 166. The grower can use no trap
crop to attract these insects away from squashes. He must
plant enough for both himself and the moths. All infested
fruits should be destroyed) ; and the melon-aphis (see under
watermelons, page 199).
STRAWBERRIES
STRAWBERRY PAMERA (Pamera vincta, Say)
This insect and the red spiders are the most common and
persistent pests of strawberries in Florida. Fortunately they
do not make their appearance in destructive numbers until the
bearing season is nearly over. But if the grower attempts to
carry his vines thru the summer he most invariably has trouble
with the pamera. The insects breed so rapidly and are so incon-
spicuous in color, size and habits, that they usually become very
numerous before they are noticed. The young are often mis-
taken for yellow ants which they closely resemble in size and
color but the presence of the darker, winged adults will readily
distinguish them. When disturbed they run over the ground
much more rapidly than ants.
This insect is one of the common causes of "buttons,"
which are berries that in some early stage of development cease
growing and become hard, dry and brown. If attacked when
very young the berry turns brown and dries up. Later, the in-
sects attack the crown of the plant which is quickly killed if the
bugs are numerous. They will often kill the plants in a bed
which the owner was keeping for propagating purposes.
The adult insect is oblong in shape, resembling the chinch-
bug, the most destructive enemy of St. Augustine grass in
Florida. Indeed, it belongs to the same family. It is black
with yellow markings and is about 1/5 of an inch long.
According to Prof. A. L. Quaintance, who described this
insect in Bul. 42 of the Fla. Agr. Exp. Sta., the eggs when first
laid are white, but by the third day turn yellow, and by the
fifth day are bright red. They hatch on the eighth day. The
newly-hatched larva, like the egg, is bright red. It soon turns
brownish, but the red persists on the end of the antennae, base
of the beak, legs and abdomen. Larvae become adults in 16
days. The females begin to lay eggs about 3 days after becom-
ing adults. The time required for a life-cycle is 27 days.
This insect is very abundant upon a wild spurge (Euphor-
bia sp.), which may be its native host plant. At least this not
Florida Agricultural Experiment Station
uncommon weed should be eradicated if found near the straw-
berry beds. It is a small light-colored plant that lies very flat
on the ground and has a milky juice.
Control.-The writer has found a brood of young chickens
efficacious in ridding a small patch of strawberries of these
insects. Frequent watering with a heavy pressure from the
garden hose is also very effective. Like its relative, the chinch-
bug in St. Augustine grass, a great many are killed by heavy
dashing rains, consequently their numbers rapidly decrease with
the advent of the rainy season.
On commercial beds insecticides must be used. Tobacco
extracts as applied to thrips are very effective. Kerosene emul-
sion will kill them but is likely to taint the fruit. Whatever is
used, strong pressure is necessary to drive the spray into the
crown of the vines where the insects are hidden.
The larger Pamera bilobata and Paromius longulus also at-
tack strawberries. Control measures are the same.
TARNISHED PLANT-BUG
The tarnished plant-bug (fig. 79) causes much the same
type of injury as the Pamera. For control measures and de-
scription consult the section on celery insects, page 149.
RED SPIDERS
Red spiders are very injurious to strawberries and a severe
infestation will quickly put an end to bearing. The pests col-
lect chiefly on the under side of the leaves and on the young
fruit which they cause to turn brown and hard. For remedies
see under peas, page 175.
THRIPS
There are two species of thrips attacking strawberries in
Florida. The more common one is the orange-yellow Florida
flower-thrips (Frankliniella bispinosus projectss. The injury
it inflicts is very similar to that described under tomatoes (see
thrips, page 192) and the remedy is identical. In applying the
tobacco and soap solution it is best, in order to avoid tainting
the fruit, to spray the plants immediately after picking. The
odor and taste of the insecticide will disappear by the second
day which is the usual interval between pickings.
The other species, the black garden-thrips (Leptothrips
mali) is not nearly as abundant. The method of control is the
same.
Bulletin 151, Truck and Garden Insects
NEGRO BUGS (Corimelaena pulicaria and Pangaeus bilineatus)
These are small, roundish, shining, black bugs which are
very common on blackberries and dewberries and are found on
strawberries. They damage the berries by sucking the juices,
but more by the odor they leave on them. This is very nauseous,
similar to that of bed bugs.
The adult bugs are about 1/ of an inch long and black with a
white stripe on each side. The middle piece of the back (scutel-
lum) is enlarged to cover the entire abdomen, making the in-
sects look more like beetles than bugs. The sucking mouth-
parts, however, readily distinguish them. The young are brown
with yellow legs.
In Michigan, where the insects are sometimes very injurious
to celery, it has been found that a spray of crude carbolic acid
is very effective in driving them away. A tablespoonful is used to
2 gallons of water. A dust made by adding a half pint of the
acid to a bushel of lime or plaster was also found effective.
Like the tobacco extracts, they should be used just after the
Vd
I~P~.
'
FiG. 105.-Field cricket (
lus assimilis). Slightl
large. (From Fla.
Exp. Sta. Bul. 42.)
Another remedy is
berries are picked so that the odor may
leave before the next picking.
CUTWORMS
Following their usual habit of sev-
ering succulent stems, these caterpil-
lars often sever the petioles of the
/ leaves of strawberries and the stems of
the green fruit. They inflict another
type of injury, hitherto undescribed,
L' which is a variation in their usual
habits of feeding. They attack the
berries from below and hollow them
out, eating perhaps half of the berry
without severing it from the vine. The
writer had often noticed this type of
injury before the cause of it was de-
S termined by the capture of the culprit
red-handed." Since the first capture
many others have been made.
Gryl-
yen- A little digging about an injured
Agr.
berry will usually unearth the cutworm.
the poisoned bait described for cutworms
under cabbage insects, page 137.
Florida Agricultural Experiment Station
STRAWBERRY FLEA-BEETLE (Haltica ignita)
This insect eats holes in the leaves of strawberry plants.
It is sometimes quite destructive in a bed of them, even to the
point of defoliating the vines. This flea-beetle (fig. 62) is
about 1/5 of an inch long and of a yellow-bronze color. Control
measures are the same as for the species attacking the beet
(see page 136). If the attack occurs during the picking season
the use of arsenic in any form should be avoided. Bordeaux will
repel it altho it is not as effective as lead arsenate.*
FIELD CRICKET (Gryllus assimilis)
The field cricket (fig. 105) is commonly found under the
mulch in strawberry beds. Prof. A. L. Quaintance, who made a
study of them in Lake City, found them very injurious. The
following is quoted from his Bulletin No. 42 of this Station, p.
596.
From the slyness and alertness of these insects, they can rarely be
approached unawares, and studied in their normal mode of living. Exami-
nations of many different plants from which crickets have been frightened
led me to believe that the cricket must undoubtedly be classed as an enemy
to the strawberry grower. In the majority of cases where crickets were
frightened from plants, much of the ripe fruit has been eaten into in such
a way that decay would soon result. A hole an eighth of an inch thick
or more is sometimes eaten into the fruit, but more usually several smaller
pits are eaten out. If an individual cricket were to confine its attention
to one berry, the damage would not be so great, but it does not seem to
do this, but attacks several different berries. In this way a single insect
is able to occasion the destruction of a considerable number of ripe fruit
in a short while."
Young chickens in a patch will quickly destroy these in-
sects. Quaintance recommends the poisoned bait.
OTHER STRAWBERRY PESTS
Other insects more or less destructive to strawberries are:
Greenhouse whitefly (see under sweet potatoes, page 187) ; white
grubs (see under potatoes, page 178) ; leaf-footed plant-bug
(see under potatoes, page 178) ; and grasshoppers (see under
general garden pests; page 122).
SUNFLOWER
This common garden annual is severely attacked by plant-
bugs. They first attack the stem of the young plant and when
the head is formed shift their attention to that. They suck the
juices from the forming seeds and continue their attacks until
the seeds are quite mature. By harvest time many seeds are
empty shells, valueless as poultry food. The most common of
these bugs is the leaf-footed plant-bug (see under potatoes, page
*See page 205, Strawberry Flea-Beetle and Crape Myrtle.
Bulletin 151, Truck and Garden Insects
178), the pumpkin bug (see under cowpeas, page 161), and the
big-footed plant-bug (see under potatoes, page 177).
Hand-collecting is a comparatively simple matter as the
bugs are massed on the heads of the plants. One should use a
net, or a pan of kerosene. If the pan is held under the head
which is then given a sharp jar, most of the bugs will fall into
the kerosene and be killed.
Other insects attacking sunflowers are: Red spiders (see
under peas, page 175; and cutworms (see under cabbage, page
137.)
SWEET POTATOES
SWEET-POTATO CATERPILLARS (Prodenia spp.)
Several species of caterpillars are likely to attack this
plant, particularly during August and July. If not combated
they often defoliate an entire field. They are velvety-looking
caterpillars which belong to the cutworm family but have more
of the habits of army worms as they feed during the day, and
have a strong tendency to collect in colonies so that defoliation
commonly begins in one or two places in a field. Indeed, one
species, P. commelinae (fig. 106, A), is called "the semi-tropical
army worm." The most common
S:species, P. ornithogalli, is about
2 inches long before it enters the
ground to pupate. (Fig. 106, B.)
In color it is a dark; rich, vel-
vety brown, almost black. The
life history of these caterpillars
SA is similar to that of cutworms.
SControl.-The quickest and
: most thoro method of killing
these worms is to spray with
B lead arsenate, using 1 pound of
the powder to 50 gallons of
water. Two pounds of quick lime
FIG. 106.-Sweet-potato caterpillar added will prevent any burning
moths: oaa na added will prevent any burning
moths: a, Prodenia commelinae;
Srod rnithogalli. Natural effects. The spraying should be
done in the early morning so that
the spray will evaporate quickly. A cheaper method is to dust
the plants in the early morning when the dew is on them. For
this purpose use a mixture of 1 part of the arsenate to from 1
to 3 of air-slacked or hydrated lime. This can be applied by
Florida Agricultural Experiment Station
means of a coarse burlap bag shaken over the vines, but a
better method is to use a dusting machine.
The cheapest method of dealing with the caterpillars and
one that has been entirely successful in many cases, is to poison
them with the Kansas bait; directions for making it are given
under cutworms. (See under cabbage, page 137.) The bait
should be put out about sunset or on cloudy days so that it will
not dry out quickly.
Birds, including chickens and turkeys, are very fond of
these caterpillars. They are also attacked by parasitic flies and
wasp-like enemies and preyed upon by true wasps.
FALL ARMY WORM
The fall army worm often attacks sweet potatoes. It is a
smaller, slimmer caterpillar than the sweet-potato caterpillar
and control measures are the same. Its description and life
history will be found under corn. (See page 155.)
HORNWORMS
The larvae of several hawk-moths or sphinx-moths, also
called "humming-bird moths" from their habit of hovering
over flowers, often attack sweet potatoes. These do not work
in armies" but they are so large that a few scattered in-
dividuals can do considerable damage and should be collected
by hand. For the life history and enemies of these insects see
under tomatoes, page 194.
GOLDBUGS, OR TORTOISE-BEETLES
These are pretty little beetles which eat holes in the leaves
of sweet potatoes. They are usually common but are seldom
present in sufficient number to be considered a troublesome pest.
Nevertheless, the entire damage amounts to considerable. The
beetles are round to oblong in shape and about 1/4 inch long.
Two species are common in Florida. The more abundant (Cop-
tocycla aurichalcea) is of a beautiful iridescent, golden color.
It looks like a drop of gold against the deep green of the leaf,
on the upper surface of which it is commonly found. The other
(Chirida guttata) has a ground color of duller yellow with a
harp-shaped black pattern stretching completely across the back.
These beetles can be poisoned readily with lead arsenate.
SWEET-POTATO WHITEFLY (Bemesia inconspicua)
This relative of the destructive citrus whitefly is a severe
pest to sweet potatoes in the southern part of the State, par-
Bulletin 151, Truck and Garden Insects
ticularly to late-planted vines. Farmers in some communities
have abandoned the attempt to grow a late crop on account of
the ravages of this pest. With this insect, like all whiteflies,
it is the larva which does the damage by sucking the sap from
the leaves. The adult, which is smaller than the citrus whitefly,
lays her eggs on the under side of the leaves. These hatch in
about a week. The young crawl about until they find a suitable
place to insert their probosces or beaks. Having once inserted
them, they are unable to withdraw and are anchored firmly for
the remainder of their larval days. If the beak is pulled out
forcibly, the larva is unable to reinsert it and will die of star-
vation. These larvae are very flat, roundish bodies about 1/12
of an inch long, attached snugly to the under side of the leaves,
which they resemble so closely in color as to be inconspicuous.
Like the citrus whitefly, these larvae excrete a honeydew, a
sweet substance in which grows a black fungus called sooty
mold. Like that species too, but to a less degree, they are at-
tacked by a bright red parasitic fungus, the red Aschersonia.
Control.-The larvae can be killed by either a strong soap
solution or kerosene emulsion. This must be applied soon after
the eggs hatch, otherwise the insects will have done their work.
As these larvae are very small when first hatched, it will be
necessary to keep close watch on the plants and spray as soon
as many larvae are seen.
SWEET-POTATO ROOT-WEEVIL (Cylas formicarius)
This extremely dangerous pest in tropical countries has
obtained a foothold in many places in Florida. It is a small
FIG. 107.-Work of sweet-potato root-weevil. (Original.)
snout-beetle which bores thru the roots, ruining them (fig.
107, even for stock food. The weevil attacks the potatoes in
Florida Agricultural Experiment Station
the field, entering near the stem. It is particular destructive
in pits where sweet potatoes are stored. Not only do the adult
beetles mine the roots, but they breed there, and the white,
soft-bodied, maggot-like grubs continue the destruction.*
The adult beetle is about 1/4 of an inch long. The abdomen
is cylindrical in shape and shining blue. The thorax, head, and
legs are brown, and the long beak which is held out straight in
front is black. The thorax is small and the legs long, giving to
this pretty beetle a superficial resemblance to an ant; hence the
name formicarius.
Control.-All infested potatoes should be sorted out at once
and fed to stock. Hogs should be turned into the field after
the potatoes are dug to clean up all refuse of the crop. Where
this has been thoroly done the pest has been almost extermi-
nated.
OTHER SWEET POTATO PESTS
Other insects which attack sweet potatoes are: Bean-
jassid (see page 129); grasshoppers (see page 122); large
carrot-beetle (see May-beetles, page 178) ; and wireworms (see
page 153).
TOMATOES
BOLLWORM OR TOMATO FRUIT-WORM (Heliothis obsoleta)
This insect is the most serious pest of the tomato in Flor-
ida. It is the same species that is so frequently found in the
ears of corn, particularly sweet corn. It is then known as the
"corn ear-worm." It also attacks green peas, beans, and other
plants, and is particularly destructive to cotton, being then
known as the bollworm. The last generation of the season,
during September and October, feeds largely upon the seeds of
beggarweed. For an illustration of this insect and its life his-
tory, see corn and okra insects, pages 151 and 171.
The tomato is most severely attacked in the spring and
early summer. The eggs are laid on the leaves. The young
larvae feed there for a day or so, but soon migrate to the stems,
into which they bore. They are prone to wander, however,
and the young tomatoes, as soon as they are set, are attacked
by the caterpillars which entirely desert the stems. Here, as
on other food plants, they bore into the fruit and mine the in-
side. Again their restless habits come into play, for, instead of
confining themselves to one fruit until it is consumed, they will
desert the first to attack a fresh one, which in turn is eaten
*Termites (see page 206) make similar tunnels in sweet potatoes.
Bulletin 151, Truck and Garden Insects
enough to be spoiled and then deserted for another. In this
manner, a single caterpillar may spoil two or three tomatoes a
day, and thus do much more damage than would be represented
by the amount of food actually consumed.
Control.-Arsenicals.-While feeding inside a good-sized
tomato, the caterpillars are, of course, out of reach of arseni-
cals, but their restless habits offer the grower an opportunity
to get at them. They rarely remain in one fruit until their
growth is completed, but after feeding in it for a day or so,
crawl out and attack another. While making their way into
fresh tomatoes they may be poisoned by any arsenical with
which the fruit has been sprayed. Especially when the first
fruits are small, the chances for poisoning the insects are good.
The worms are not able, because of the small size of these
fruits, to eat their way inside, but remain on the outside, and
may eat out sections of several in a single day. These first
fruits are the most valuable part of the crop, which is an addi-
tional reason for applying poison early. A third reason for
applying the arsenicals quite early, when the very first fruits
are the size of marbles or smaller, is that then there can be no
possibility of hindering the sale of the fruit. By the time the
fruit is ready to pick, the enlargement due to growth will have
destroyed all signs of the spray, even if there has been no rain.
The chances of poisoning the consumer, even if the fruit is
sprayed only a day or so before picking, are negligible. Using
lead arsenate at the rate of 2 to 3 pounds to 50 gallons of water,
the amount that would be left on each fruit would be so small
that the stomach of the consumer could not hold enough toma-
toes to enable him to get an injurious dose of the arsenical,
even if the tomatoes were not washed before eating. However,
any trace of the spray on the fruit at the time of marketing
would probably lower the price. For this reason it is recom-
mended that the spraying be discontinued a week or ten days
before the first picking. The first spraying should be given
when the earliest tomatoes are the size of small marbles. A
week later, if there is no rain, a second spraying can be given.
Should it rain shortly after the first spraying, it would doubt-
less be advisable to apply a second spray within three or four
days after the first. Even a single spraying will greatly reduce
the percentage of infestation.
It is recommend that, in using the lead arsenate spray, 2
pounds of lime be added to the liquid to prevent burning.
Florida Agricultural Experiment Station
The newer arsenical, zinc arsenite, has several advantages
over lead arsenate for this work. It is cheaper in that only 1
pound to 50 gallons of water is used. It is decidedly less poi-
sonous to man than is lead arsenate and therefore, injurious
effects are even less probable.
If spraying with bordeaux mixture at this time, the arsen-
ical, either lead arsenate, zinc arsenite, or paris green, may be
added to the bordeaux.
Corn as a Trap Crop.-The bollworm prefers corn, espe-
cially sweet corn, to any crop grown in Florida. During the
summer of 1914, some successful results were obtained in the
use of sweet corn as a trap crop. On one small plot of toma-
toes planted next to sweet corn which was just coming into
silk when the earliest tomatoes were forming, there were no
worms at all, while a field a quarter of a mile away averaged
20 percent infested fruit. Observations would indicate, how-
ever, that the corn must be planted very close to the tomatoes
to provide protection. We recommend that 10 to 20 rows of
tomatoes alternate with 2 rows of corn. If a single row of
corn is planted across the field it usually does not get thoroly
pollinated and the ears will not be sufficiently attractive to
prevent the caterpillars from wandering to the tomatoes. Also
the corn must be planted at such a season as to be in an at-
tractive condition when the first tomatoes are forming, that is,
it must have young silks, otherwise the insect prefers the toma-
toes. This corn must be destroyed before it has matured
enough to be unattractive to the worms, otherwise it will in-
crease rather than decrease the number of worms in the toma-
toes. Many larvae will crawl from the corn to the tomatoes,
and many moths whose larvae matured on the corn will emerge
from the cocoons and fly to the tomatoes. The corn can be left
until the ears are sufficiently mature for roasting purposes, but
by no means should they be left to ripen in the tomato field.
Cowpeas planted in the corn will afford shade in which the
moths can hide during the day and thus make the trap crop
more attractive to the moths and increase its efficiency.
Destroy Wormy Fruit.-All wormy fruit should be picked
and removed from the field, and so disposed of as to destroy the
larvae. Stock, hogs, and chickens will eat a limited amount of
these wormy tomatoes, especially if they do not have access to
other green food. Where the acreage of tomatoes is large, the
most practical method of disposing of these wormy fruits is to
6
Bulletin 151, Truck and Garden Insects
dump them into a pond, or to bury them. They should be cov-
ered with at least a foot of well-packed soil (or more if it is
very sandy) to ensure that the larvae or the moths will not be
able to make their way to the surface. The practice of dump-
ing the wormy and cull fruits beside the packing house or along
the roadway cannot be too severely condemned. A large per-
centage of the worms will complete their development in the
pile, pupate in the ground and later come out as moths to
augment later infestations. If a wormy tomato is thrown down
in the field, the caterpillar will soon attack another tomato; or,
if full grown, will enter the ground to pupate. It would be
better not to pick the tomato at all than to throw it on the
ground in the patch, as the caterpillars will more quickly leave
the detached and wilting fruit and attack a new one. Wormy
tomatoes can perhaps best be sorted out at the packing house.
If these caterpillars are destroyed it will greatly reduce the
number in succeeding generations. This has been thoroly proven
by experiments on a large scale. In one experiment conducted
by Director P. H. Rolfs, the wormy tomatoes were carefully
picked up from one field while in a neighboring field they were
neglected. In the former, at the close of the season, there was
scarcely any increase in the number of worms, while in the
latter field, 80 percent of the fruits of the later pickings was
ruined. It is not too much to say that for every worm the
grower destroys early in the season he will save a crate of
tomatoes later on. Each moth may lay as many as 500 eggs
and there is a generation every 30 days under the most favor-
able weather conditions.
Clean Up the Field.-As soon as possible after the close of
the picking season, the vines with infested fruit should be
burned or plowed under. This is very important as a means of
combating, not only this, but other insects and fungus diseases
as well. Growers sometimes object to burning old plants on
the theory that they are destroying so much fertilizer which
would be returned to the soil by the rotting plants. While it is
true that some of the organic matter would be destroyed, the
loss is infinitesimal in comparison with that resulting from the
injuries caused by the insects and fungi if they are allowed to
live over.
FLORIDA FLOWER-THRIPS (Frankliniella bispinosus projects)
This is a very common insect usually found in small num-
bers on a variety of blossoms, including those of tomatoes and
Florida Agricultural Experiment Station
citrus. Usually it is not sufficiently abundant in the tomato
field to do any harm. But occasionally (as during the spring
of 1912) it may do a great deal of damage. It is a minute,
soft-bodied insect, about 1/25 of an inch long, with orange head
and thorax, and lemon-yellow abdomen. The latter it often
curls up over its back in a threatening manner when disturbed.
Under a lens it is seen to have brownish-red eyes, and short
antennae with eight joints on them; also short wings which
are very delicately fringed. (See illustration of onion thrips.)
The wings appear quite inadequate to carry the insect, but this
is far from being the case, as the adults fly quite readily for a
long distance. They are active creatures and crawl about a
great deal. The young (or nymphs) are very similar to the
adults, but lack the wings.
The life history is very short, a generation occurring every
2 or 3 weeks under favorable conditions. The eggs are laid
just beneath the surface of the plant tissue in a shallow slit.
Damage.-The young, upon hatching, at once attack the
tenderest part of the blossom or bud. The stamens seem to
suffer first, but, as there is always much more pollen produced
than can be used, no particular harm is done. If there are only
a few thrips present, say one or two to each blossom, they
usually find enough food in the stamens and do no harm to
the crop. It is even possible that they are of service in cross-
pollinating the blooms. But where there are a dozen of them
in a single bloom they attack other parts. Investigations in the
tomato fields in the spring of 1912 showed as high as twenty
thrips to a single bloom. When present in such numbers, vari-
ous parts of the flower are attacked and seriously injured,
especially the pistil. This turns black and shrivels up. Soon
after, the whole bloom turns yellow and falls off. If this is
repeated for all the blossoms on the first three or four clusters,
which was often the case in that year, the crop is ruinously
shortened, as these first fruits are the paying ones.
Remedy.-Tobacco decoctions are very effective against this
insect. The difficulty lies in reaching the thrips with the spray,
as they are under the stamens and sheltered by them. But they
are active creatures, and when the blossom is disturbed, at once
come out and try to get away. It is this habit which enables
the growers to reach a large number of them with the spray.
In spraying, therefore, care must be taken to so thoroly cover
the blossom or bud with the solution that the insects cannot get
Bulletin 151, Truck and Garden Insects
out without getting wet by it. Pass down the rows rather
slowly and let the spray play for a second or two on each cluster
or "hand." This not only insures a thoro drenching but also
gives the insects time to crawl out to where the spray can hit
them. Use as much pressure as possible, for the double pur-
pose of driving the liquid into the blossoms and of frightening
the insects out by the force of the spray against the flowers.
Different tobacco decoctions, of which there are many on
the market, vary much in the strength of nicotine present, and
consequently, in the proportions in which they should be mixed
with water. Black leaf 40 should be used in about the pro-
portion of 1 part to from 1000 to 1800 of water. The weaker
solutions (as black leaf 2 1/3 percent) in about 1 to 100; while
1 part of home-made tobacco extract should be used with about
10 of water.
It is advantageous to put into the solution something to
give it better sticking qualities. The writer used the following
mixture on tomatoes during April, 1912, and killed about three-
fourths of the thrips present. This solution was previously
found very effective against the orange thrips in California:
Commercial lime-sulphur........................... 2 1/3 quarts
Black leaf 40 ..................................... 3 1/2 ounces
W ater ........................................................ 50 gallons
Lead arsenate or zinc arsenite can be substituted for the
lime-sulphur in case the grower wishes to kill the tomato worms
or other biting insects at the same time. Four or five pounds
of whale-oil soap may also be substituted for the lime-sulphur.
Flour paste makes an excellent spreader for these tobacco ex-
tracts. Take 2 pounds of cheap flour and stir it into 2 gallons
of hot water. Add this paste to the 50 gallons of spray mate-
rial.
Since tomatoes should be regularly sprayed with bordeaux
for fungus diseases, the best plan of all is to place the tobacco
in the bordeaux solution.
HORNWORMS (Phlegethontius quinquemaculata and P. sexta)
Because of their large size, these insects attract the atten-
tionh of the grower, but the total amount of damage actually
dBne to the tomato crop is far less than in the case of any of
the prfeeding insects. The moths of this family (Sphingidae)
are known as sphinx moths," from the habit the larvae have
of elevatilig the front end of the body when at rest, arching the
head doin Alittle, and remaining perfectly immovable in this
-Florida .Agricultural. Experiment Station
position. They are also known as hawk-moths because of their
rapid flight, and as humming-bird moths from their habit of
hovering over their favorite blossoms like those birds. They
fly about at dusk, and on very cloudy days, visiting flowers with
long cQrollass.such as jimsonweed and petunias. The body is
very large and in order to carry it the moths move their wings
with great rapidity so that, like the birds, they hum. Another
characteristic is the long proboscis -which is.used to sip the
nectar from the deepest flowers.
There are two species of sphinx moths most likely to prove
destructive to tomatoes in Florida. The Southern hornworm
(P. sexta) (fig. 108) ranges far into South America and is much
FIG. 108.-Southern hornworm: Moth. Natural size. (From Fla. Agr.
Exp. Sta. Bul. 48.)
the more common one. According to A. L. Quaintance (Bul.
48, Fla. Agr. Exp. Sta.) this worm is about 6 or 7 times as
numerous in Florida as the other. The Northern tobacco worm
(P. 5-maculata) ranges farther north, and does not occur much
south of the United States. The larvae may be distinguished
by the color of the horn, which is black in P. 5-maculata and red
in P.sexta. (Fig. 109.) The stripes on the sides are also dif-
ferent, being distinct V's in the former.
The damage done, and the treatment, are the same for
both. The adults lay grayish-yellow, smooth spherical eggs in
the spring, singly on the lower surfaces of leaves. The eggs
measure about 1/28 of an inch in diameter, and hatch in 3 days
into small green larvae. These eat ravenously, grow rapidly,
and molt five times during the 3 weeks that are necessary for
their growth. During this time a single worm will strip a large
tomato plant of leaves. When full grown, the larvae of horn.
;195
Bulletin 151, Truck and Garden Insects
worms (fig. 109) are 3 or 4 inches long. Near the posterior
end there is a curved spine which suggests the name "horn-
worm." This is wrongly supposed by many to be a poisonous
FIG. 109.-Southern hornworm. Natural size. (From Fla. Agr. Exp. Sta.
Bul. 48.),
sting. The insect is entirely harmless. When the worms"
are full-grown they enter the ground to a depth of 3 or 4 inches,
and change to the dark red-brown pupae. The projecting
tongue-case is characteristic of the pupae of this family of
moths and enables them to be told at a glance; it suggests a
handle to the pupa. (See fig. 110.) The pupae from the first
brood of larvae appear in North Florida in July.
Natural Enemies.-The hornworms are held .
in check fairly well by their natural enemies.
Among the latter are tachina-flies, which lay
their eggs on the caterpillars, and also a minute
hymenopterous insect (Apanteles congregatus).
The eggs of these parasites hatch into minute
grubs which burrow into the caterpillar and
live on its fatty tissue but avoid the vital or-
gans, grow to full size and then emerge to form
their pupae on the outside of the host. (See
fig. 111.) These parasites have been given promi-
nent mention, because it is important that these
parasitized specimens be not crushed or other-
wise destroyed. Parasitized worms should be FIG. o10.-South-
ern hornworm:
left carefully alone, as the caterpillars will sure- Pupa. Naural
ly die, leaving the parasites to hatch out. If Fa xp.
Sta. uL 48.)
Florida Agricultural Experiment Station
the host is crushed or destroyed, the parasitic allies are also
killed. This is, of course, true of any parasitized insect. Never
killed a parasitized insect.
WHITE-LINED MORNING-SPHINX (Celerio lineata)
Its larvae occasionally infest the tomato, altho its favorite
food-plants are certain weeds, especially of the purslane family.
FIG. 111.-Hornworm parasitized by braconid-flies (Apantales con-
gregatus). (Fla. Agr. Exp. Sta. Bul. 48.)
It belongs to the same family as the tomato sphinx, which it re-
sembles in general shape but is brighter in color.
The same methods of hand-picking and spraying with
arsenate of lead are recommended for this species also.
WHITE MOLD (Eriophyes cladophthirus)
This is a disease of the tomato characterized by general
fuzziness. In its first stages it may be recognized from the
following description by P. H. Rolfs in Bul. 91, Fla. Agr. Exp.
Sta.:
"If one is standing in a tomato field shortly after sunrise, or near
sunset, and looking across the field in the direction of the sun, the plants
which are attacked will be easily distinguished from the others in the
field by a peculiar white, fuzzy appearance of the upper portion of the
stem."
In spite of its name "mold," it is not caused by a fungus
parasite, but, as was determined by P. H. Rolfs in 1892, by a
small mite closely related to the rust mite of citrus. This mite
is almost peculiar to Florida, for altho it occurs as far north as
South Carolina, it is rarely seen as a tomato pest outside of
this State.
The remedy is the same as for its close relative, the rust
mite of citrus, which is, sulphur. In this case the sulphur is
Bulletin 151, Truck and Garden Insects
-best used as a spray, which must be thoroly applied. The
formula (as given in Fla. Agr. Exp. Sta. Bul. 76) is:
Caustic soda (98 percent) .............................10 pounds
Flowers of sulphur ...........................................20 pounds
W after ..................................... .. ........ 20 gallons
Mix the sulphur in cold water to a thick paste, add the
soda and as it boils add water gradually to make 20 gallons.
This water should be added fast enough to prevent burning, but
not fast enough to stop boiling. The result will be a dark coffee-
colored liquid. Strain thru a fine-meshed cloth or spray-strainer.
Keep in tightly .corked jugs. Mix 1/2 gallon of this stock solu-
tion in 40 gallons of water when ready to use. Other remedies
are: Lime-sulphur solution, dry sulphur, and dry sulphur and
lime. The last two are frequently unsatisfactory.
PLANT-BUGS
Pumpkin bugs (see under cowpeas, page 161), the big con-
vict bug (see page 204), leaf-footed plant-bugs (see under pota-
toes, page 178), and big-legged plant-bugs (see under potatoes,
page 177), and the brown stinkbug, commonly attack tomatoes,
particularly early in the spring. They may attack the stems of
the plants in the same manner as they do those of potatoes. In
addition, the first three species are quite fond of sucking the
fruit. If the fruit is of fairly good size they cause unsightly,
hard, brown spots, where they insert their beaks, very much
as they do on beans. These spots are, however, less permanent
than in the case of the bean. The sucking of the juice, of course,
interferes with the growth of the fruit. Very young fruit may
be deformed, "cat-faced," by their attacks.
WHITEFLY
A whitefly (Aleurodes tabaci) attacks tomatoes. Badly in-
fested vines may as well be destroyed. Less severely infested
ones may be sprayed as recommended under sweet potatoes.
OTHER TOMATO PESTS
Other insects attacking tomatoes are: Cutworms (see un-
der cabbage, page 137) ; plant-lice (see under cabbage, page 144) ;
flea-beetles (see under beets, page 136) ; blister-beetles (see
under beets, page 134) ; semi-tropical army worms (see cater-
pillars under sweet potatoes, page 186); and Colorado potato-
beetle (see under potatoes, page 179).
Florida Agricultural Experiment Station
TURNIPS
TURNIP PLANT-LOUSE (Aphis pseudo-brassicac)
This plant-louse is very much like the cabbage-aphis with
which it is often found. It differs by being more hairy. The
remedy is the same as for the garden aphid which is also found
on turnips. (See plant-lice under cabbage, page 144.)
Other insects attacking turnips are: Flea-beetles (see un-
der beets, page 136); and root-maggots (see under cabbage,
page 146).
WATERMELONS
MELON-APHIS (Aphis gossypii)
This plant-louse in Florida is commonly called the Hes-
sian fly," altho it is a very different insect from the true Hes-
sian fly which devastates wheat fields in the Central States. It
is the most serious enemy of watermelons in the State and does
great damage. Not infrequently, it destroys whole fields of
many acres before a single melon has been shipped. It is a
dangerous pest of cucumbers, cantaloupes, squashes, gourds, and
other curcubits as well as watermelons. It commonly attacks
cotton and citrus and is found on many weeds and other plants.
Next to the garden aphid it is the most common and wide-
spread aphid in Florida.
The life history and enemies of this species are about the
same as those of the garden aphid. (See cabbage pests.)
Control.-There are four measures that are effective in
keeping these bugs in check: spraying, fumigating, dusting,
and clean culture.
Spraying.-The grower will probably find that the most
satisfactory method of dealing with an outbreak is to spray
with a soap and tobacco decoction. He will probably find it
cheaper to buy the tobacco extract already made, but if a sup-
ply cannot be quickly had when the first signs of aphids appear,
it is better to make his own than to delay action. Tobacco
stems and refuse are placed in enough water to cover them
well and kept at a temperature just below boiling for an hour,
or allowed to soak over night. The solution should then have
the color of strong tea. To keep this more than a day or two, add
an ounce of salicylic acid to each four gallons. Before use, it is
diluted with 10 parts of water.
The ready-made tobacco decoctions, of which there are
many on the market, vary much in the amount of nicotine pres-
ent, and consequently in the proportions in which they should
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