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Crops and Pests 


All Vegetables 

Blister beetles 10 

Cutworms 5 

Grasshoppers 12 

Stinkbugs 9 

White grubs 7 

Wireworms 7 


Beetles , . Tjjffoi i .-TO 

Leafhoppers , . . . . 9 

Maggots . . . 6 

Plant lice (aphids) 8 

Broccoli, Cabbage, Cauliflower, 
Collards, Kale, Radishes, 

Beetles 10 

Caterpillars 11 

Cutworms 5 

Harlequin bugs 9 

Maggots 6 

Plant lice 8 



Corn earworms 





Plant lice 

Eggplant, Potatoes, Tomatoes 

Beetles - ^ 




Flea beetles 


Tomato fruitworms 

Cucumbers, Melons, Pumpkin, 

Beetles . . 



Plant lice 

Squash bugs 


Now, in time of war, the need for 
maximum production of food is more 
important than ever before. Our 
Government is asking urban as well 
as rural people to contribute their 
share again this year in meeting our 
hucje food requirements. They can 
do this by growing Victory Gardens 
to supply their home needs for veg- 
etables, thus releasing food pro- 
duced from other sources to feed our 
fighters, our allies, and our workers 
on the home front. 

Twenty-two million Victory Gar- 
dens is the goal set for 1944. This 
means that we need about 16 mil- 
lion city, town, and suburban 

Insects that feed on garden crops 

584186°— 44 

must be controlled. In this guide the 
gardener will find a general discus- 
sion of insects and their control. 
Insects having the same or similar 
habits are listed together, and 
methods for combating them are 
given. No attempt is made to discuss 
each insect separately, or to give as 
wide a variety of control measures 
as commercial growers would need. 

A knowledge of insects and their 
food habits will be useful in applying 
control measures and will also lessen 
the sometimes groundless fear of 
damage they may cause. For ex- 
ample, many insects that will not 
cause crop damage will be found 
in the garden, their presence being 
merely incidental. 


On the other hand, some insects, 
such as blister beetles, grasshop- 
pers, and cutworms, feed on a wide 
variety of plants. Others, such as 
cabbage worms (caterpillars) and 
harlequin bugs, feed on closely 
related crops like cabbage, col- 
lards, kale, and broccoli. The Mex- 
ican bean beetle feeds only on 
beans, the striped cucumber beetle 
on squash and other members of the 
squash family, such as pumpkins 
and melons. 

Insects feed on plants by chewing 

holes in the leaves, sucking plant 
juices, or tunneling into the roots, 
stems, or leaves. The presence of 
the chewers is easy to detect; the 
injury caused by the other kinds 
shows up as wilting, curling, or 
stunting of the different parts of the 

Some insects are beneficial, •be- 
cause they feed on other insects that 
are pests. Some of the beneficial 
insects are ladybeetles, wasps, syr- 
phid flies, and lacewings. 

CUTWORMS attack the young 
plants of cabbage, collards, toma- 
toes, corn, and almost all other gar- 
den plants. They cut these plants off 
at the surface of the ground. These 
insects are likely to be present in 
soil that was in grass and weeds the 

year before. Newly set plants should 
be protected by collars at the time 
of planting. The collars should be 
made of paper and should be about 
the size and weight of a 1-cent post 
card. Wrap the paper around the 
plant as illustrated. Leave ample 
space for air to circulate between 
the collar and the plant, and allow 
the collar to extend into the soil 
about 1 inch. Cutworms will crawl 
from plant to plant, and each 
worm may cut off several plants. 
For this reason, any cutworms found 
should be killed. A pinch of poisoned 
bait placed at the base of each 
plant will prevent further damage. 
Also, a poison bait scattered thinly 
on the ground just before the plants 
are set will attract the cutworms.and 
the small amount of bait they eat 
will kill them. 

For making and applying bait, 
see discussion of grasshoppers (p. 


PLANT MAGGOTS destroy roots 
of cabbages, kale, radishes, and 
broccoli. Other kinds feed on 
sprouting beans, corn, and peas. 
Plants such as cabbage on whose 
roots maggots are feeding appear 
stunted, and their leaves turn bluish 
green. These insects cannot be 

controlled after plants are infested. 
Preventive measures such as treat- 
ing the seed with a mercury com- 
pound before planting may afford 
some protection. A 3-inch tar- 
paper disk (illustrated) — cut to the 
center so that it will fit snugly — if 
placed flat on the ground and 
fitted around each newly set plant, 
will afford protection. If maggots 
threaten the crop, a mercury treat- 
ment of calomel or corrosive subli- 
mate may be applied to the soil 
around the plants. Maggot injury 
to newly planted beans, corn, and 
melon seed usually occurs during 
cool, wet periods when seed germi- 
nation is slowed down. Prepare a 
good seedbed and plant shallow 
during warm periods to promote 
rapid germination of the seed. 

Avoid breathing or getting into the mouth 
dusts containing mercury compounds; avoid 
storing them; and thoroughly clean all ves- 
sels used in mixing and handling poisonous 


WIREWORMS (left) and White 

Grubs (right) feed on the roots of 
plants. These pests are very destruc- 
tive to gardens in some areas. No 
means of control on the growing 
crop is known, as any soil treatment 
sufficient to kill the worms will injure 

the plants. Some benefits can be 
obtained by crushing all the pests 
that are seen when the soil is being 
worked. When wireworms or white 
grubs are abundant, the soil should 
be treated before the crop is planted. 
Crude naphthalene flakes, used at 
the rate of V/, pounds to 100 square 
feet, worked into the soil to give 
uniform distribution to a depth of 
about 10 inches, will give control. 
Good distribution can be had by 
spreading about half the material 
evenly over the soil just before spad- 
ing or plowing and the other half 
immediately after, while the ground 
is still rough. The naphthalene 
should be worked into the soil 
promptly after it is applied. Do not 
plant until 7 days after treatment. 
To do so may injure the crop. Avoid 
planting carrots, onions, and other 
root crops on soil known to be 


PLANT LICE or Aphids are pests 
of peas, turnips, radishes, cabbages, 
cucumbers, and other vegetables. 
The leaves attacked sometimes curl 
up, enclosing the pests. Stems and 
the under side of leaves on which 
they feed often become covered 
with these tiny sucking insects, 


which sap the plant's life. Plants 
infested cannot develop normally or 
produce a crop. A nicotine sulfate 
and soap solution is a good remedy. 
Dissolve 2 teaspoonfuls of soap chips 
in 1 gallon of water and add 1% 
teaspoonfuls of nicotine sulfate. 
Mix thoroughly, and spray to hit the 
lice. If a dust is to be used, a nic- 
otine-dust mixture can be made, by 
pouring 1 ounce of nicotine sulfate 
into a quart of lime in a half-gallon 
friction-top can. Add a few stones 
to help in mixing the material, place 
lid on container, and shake thor- 
oughly for 10 minutes. Dust this 
mixture on the plant lice. Use nico- 
tine when the air is calm and the 
temperature above 70° F. Remove 
the unused nicotine mixture from 
the sprayer or duster. Keep the 
dust mixture sealed in a tight con- 
tainer for later use. 

Avoid breathing nicotine sulfate or getting 
it into the mouth. 

many vegetables. The Squash Bug 
(illustrated) feeds on vine crops, 
such as squash, pumpkin, and cu- 
cumbers. The Harlequin Bug feeds 
primarily on leafy crops, such as 
cabbage, kale, collards, and broc- 
coli. The Green Stinkbug is a 

general feeder. These bugs are all 
larger then plant lice, and persist- 
ent effort through hand-picking of 
eggs and bugs will give much 
control. Cleaning up and destroying 
crop refuse after harvest will destroy 
many bugs that otherwise would 
attack crops the next year. Leaf- 
hoppers belong to another group of 
sucking plant bugs and are the 
small, usually pale green, very 
active insects that readily fly from 
the plant when they are disturbed. 
They damage beans and potatoes 
by sucking the juice from the plant 
and cause a disease called hopper- 
burn. Applications of sulfur will give 
some protection. Potato growers use 
bordeaux mixture to control leaf- 
hoppers. Pyrethrum powder, if fresh, 
used alone or mixed with dusting 
sulfur, will give the best control of 
leaf hoppers. 

(See pyrethrum, under Insecti- 
cides, page 15.) 


BEETLES chew holes in the leaves 
of plants such as beans, potatoes, 
eggplants, turnips, cucumbers, and 
melons. The Bean Beetle (illus- 
trated) and the Potato Beetle in both 
the hard-shell and the young stage 
eat the plant leaves. Blister Beetles, 


Cucumber Beetles, and Flea Beetles, 
feed on the leaves of plants only 
when in the hard-shell (adult) stage. 
Flea beetles are small, dark insects, 
and move so rapidly they often pass 
unnoticed. They riddle the leaves of 
plants with small holes. Newly set 
plants such as tomatoes and egg- 
plants, especially while wilted, are 
attractive to flea beetles. Eggplants 
and potatoes are subject to flea 
beetle attack at all times, whereas 
cabbage, kale, radish, and turnip 
seedlings are more susceptible to 
damage as they come through the 
ground. The small gardener can 
pick the larger beetles off the plants 
by hand and thus protect his crops. 
Rotenone or cryolite applied lightly 
but thoroughly to both the upper 
and lower surfaces of the leaves 
will afford protection from beetles. 
Cryolite can be used until the edible 
parts of plants begin to form (see 
caution on page 15). 

CATERPILLARS eat the leaves 
of garden plants, especially cab- 
bage, kale, collards, cauliflower, 
and broccoli; also tomatoes. If 
these "worms" are not checked, 
they may ruin the crop. Pick off the 
pests by hand and destroy them. A 

mixture of cryolite, dusted or 
sprayed on plants at weekly in- 
tervals as long as necessary will 
control these insects. Care should 
be taken to cover both surfaces of 
the leaves. Cryolite should not be 
used on .cabbage, cauliflower, or 
heading broccoli after the head 
begins to form, nor should it be used 
on any leafy vegetable intended for 
immediate consumption. If cater- 
pillar control becomes necessary 
after heading or fruiting begins, 
dust crops such as cabbage with 
rotenone dust. Reach the innermost 
parts of the plants as well as both 
sides of the leaves. Rotenone is of 
little or no value for "worms" that 
feed on tomatoes. If treatment of 
tomatoes is necessay after plants 
have fruited, use cryolite, but be 
sure to wipe or wash the fruit 
carefully before it is eaten or 


GRASSHOPPERS chew the leaves 
and fruits of practically all vege- 
tables. In some areas they are 
destructive almost every year, in 
others they seldom cause damage. 
Grasshoppers can be controlled by 
the use of poison baits. In the Western 

and Great Plains States, where 
extensive grasshopper control pro- 
grams are carried on, ready-mixed 
baits are available. Where ready- 
mixed baits cannot be procured, a 
bait can be prepared by mixing — 

1 quart of wheat bran or rolled oats. 

2 level teaspoonfuls of paris green. 

When these dry materials are 
thoroughly mixed, add enough water 
slowly while mixing to make a ; 
crumbly mash in which every flake 
is moist and carries some poison. 
About 1 pint of water will be re- 
guired. The bait should be scattered 
thinly over the ground. One quart 
of mixed bait is enough for one 
application to 2,000 square feet. 
Apply the bait in the morning when 
the temperature reaches 68° F. or 
higher. Since grasshoppers usually 
come from uncultivated areas out- 
side the garden, these areas as well 
as the garden should be baited. 


BORERS tunnel into the stems and 
roots of squash, pumpkins, cucum- 
bers, melons, corn, and other plants. 
Some borers hatch from eggs laid 
on plants; others migrate from 
weeds in the garden. Therefore keep 
the weeds down. Squash borers 
(illustrated) tunnel into vines and 

cause them to wilt and die. Reduce 
damage by spraying plants four 
times, at weekly intervals, with a 
strong solution of 1 part nicotine to 
100 parts of water, when the first 
blossoms appear. Borers can often 
be located in wilted vines by the 
yellow, waxy material ' near the 
point where they cut through the 
stem. Slit the stem at this point with a 
sharp knife, and crush or remove the 
borers. Immediately cover the stem 
with moist earth to prevent drying 
of the injured plant tissue. Water 
the vines frequently until new roots 
begin to form. Damage to corn by 
the European Corn Borer can be 
reduced by the application of rote- 
none spray or dust. Get the insecti- 
cide into the center of the plant 
where the tassel forms, and between 
each leaf and the stalk. Four appli- 
cations 5 days apart, beginning 
about June 15, should be made on 
corn knee high or higher. 


Fruitworm (illustrated) feeds on 
tomato fruits and corn ears. The 
larger worms make holes about as 
big around as a lead pencil in the 
fruits. Enclosing fruit clusters in 
paper bags will offer some protec- 
tion. Dusting the plants with cryo- 

lite when fruit begins to form also 
will help. Repeat applications every 
10 days, or after each rain, as long 
as injury persists. Dusted tomato 
fruits should be washed thorough- 
ly before they are eaten or mar- 
keted. Corn earworms once inside 
the ear cannot be controlled. Stop 
them with a medicinal mineral oil, 
or, preferably, a commercially pre- 
pared oil with another insecticide 
added to make it more effective. 
Place the oil in the silk about one- 
half inch inside the tip of the ear. 
About one-fourth of a teaspoonful, 
or 20 drops, to each ear can be 
applied with an eyedropper or an 
oilcan. Wait at least 3 days after 
the silks first appear at the tip of the 
ear before applying the oil. By that 
time the silks should be wilted and 
the tips beginning to turn brown. 
Earlier treatment will damage the 
ear, and later treatment may not 
give good control. 


INSECTICIDES are the chemicals used to 
control insects. However, the home gardener 
cannot afford to stock all kinds. Only those 
necessary to give practical control of the 
most common insects are recommended in 
this guide. When in doubt about the mixture 
to use, follow directions on the package. 
Rotenone and pyrethrum are excellent 
garden insecticides, but the supply, espe- 
cially of pyrethrum, is limited. These ma- 
terials, if available, should be restricted to 
use on vegetables, at the time the edible 
parts are forming, for insects that cannot be 
controlled by other measures. 

The following insecticides are poison- 
ous to human beings as well as to 
insects. Caution should be taken in 
storing and handling them. 

Cryolite gives good control for many 
chewing insects, and the national supply is 
expected to be adeguate. Local supplies 
will depend on local dealers. Do not use 
cryolite on leafy vegetables, or on the 
exposed parts of vegetables such as tomato 
fruits, cabbage, cauliflower or broccoli 
heads, or on string (snap) beans. 

Nicotine sulfate, used to control a number 
of insects, especially plant lice, is expected 
to be available in guanlity sufficient to 
meet the demand by Victory gardeners. 
Nicotine dusts and sprays mixed for use 
must be kept sealed tightly, because they 
lose their strength rapidly. To give best 
results, nicotine dusts or sprays must be 
directed to hit the insects and used when the 
air is calm and warm. 

Arsenicals, such as calcium arsenate 
and paris green, are sometimes used to 
protect garden vegetables, but in some 
areas they cause injury to more tender 
plants. Such insecticides should not be 
used on the edible part of the plant. 

Naphthalene has a limited use for con- 
trolling pests. Its principal use is against 

All mercuric compounds are poison- 
ous, and mixtures containing copper 
sulfate, which is the principal element 
in bordeaux mixtures, are more or less 
poisonous to men and animals. In 
handling and mixing these, also be care- 
ful not to breathe them or get them into 
the mouth. 


Dusters and sprayers are the equipment used to apply 
insecticides. The Victory gardener will have to depend on 
the kind of duster or sprayer available. Many of the metals 
formerly used to make such equipment have gone to war. 
Commercially prepared applicators will give best results. 
However, use of home-made devices such as shaker cans 
or sack dusters will offer some protection to garden plants. 

For more detailed informa- 
tion on the control of insects 
affecting your Victory Garden, 
see your county agricultural 
agent, consult your State agri- 
cultural college, or write to the 
United States Department of 
Agriculture for Miscellaneous 
Publication 525, A Victory 
Gardener's Handbook on In- 
sects and Diseases. 

Extension Service and 
Bureau of Entomology 
and Plant Quarantine 



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