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is bad practice in truck-gardening to grow two successive crops of a 
vegetable, or of nearly related vegetables, successively, on the same 
piece of land; and, further, a crop should be planted as far as possi- 
ble from the location of the same vegetable the year before. Es- 
pecially is rotation desirable when the crop was badly damaged by 
insects the previous year. Some of the more important insects 
whose injuries may be checked or controlled by this method, are cab- 
bage and onion maggots, potato-beetles, wireworms, white-grubs, 
and cutworms. 
Fall Plozving. — Another important means of insect control is 
fall plowing. In the northern part of Illinois, where the winters are 
usually severe, the value of this measure seems considerable, for its 
main object is to bring the insects in the soil nearer to the surface, 
where they may be killed by the cold. It is necessary in such locali- 
ties to plow as late in fall as possible, when the insects are more or 
less inactive and unable to go very deep into the ground. Disking 
and harrowing in the fall is often helpful. 
Time of Planting. — It is often possible to avoid insect attack by 
either early or late spring planting. The object in planting early is 
to have the crop well started and sufficiently advanced to withstand 
insect attack when it occurs; while the object of late planting is to 
bring the crop on after the disappearance of the insect likely to in- 
jure it. I have known of but one instance of such benefit derived 
from early planting, and this was in the case of the onion-maggot. 
Late spring planting is a successful measure of protection against 
some insects, such as cutworms, the striped cucumber-beetle, flea- 
beetles, etc. 
Barly Detection of the Presence of Insect Pests. — Usually an in- 
sect has already done much damage to a crop before its presence is 
known, and often it is discovered too late for the successful applica- 
tion of remedies. This makes it necessary for the gardener to keep 
vigilant watch of his crops in order to know when to spray or other- 
wise to treat them; that is to say, he should detect the presence of 
an injurious msect in his garden almost as soon as it appears. 
Insect injury may be recognized by the actual detection of the 
culprit; by the failure of seed to germinate; by injury to the leaves; 
by a wilting of the plants ; by the wilting or curling of the leaves, 
caused by aphis attack; by an uneven stand; or by the slow growth 
of the plants. 
The more important insects known to be injuring garden prod- 
ucts in Illinois will now be discussed under the various crops, taken 
up in alphabetical order. Methods of preparing the principal in- 
secticides used bv the srardener are given at the end of the article. 
