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The second, or larva or worm state is the one in which 

 most insects do their greatest amount of injury, since it is 

 here that most of the growth and feeding takes place. Many- 

 insects are injurious only in this larva stage, as our cotton- 

 worm, cabbage-worm, cut-worm, etc., and all other moths 

 and butterflies. Some exceptions to this rule are to be found, 

 as in our grasshoppers and most beetles, that do as much 

 damage in the adult as in the larva stage in many instances. 

 While again, the Rosechafer that does little or no damage 

 in the larva stage, as an adult, does much injury to our vine- 

 yards. The larva or worm does not resemble in the least 

 the adult insect in most cases, and hence unless one be 

 familiar with the subject, he can not tell the adult insect by 

 the larva. The caterpillar or worm changes to a butterfly 

 or moth, the maggot to a fly, and the grub to a beetle. It 

 is in this second stage that most insects are to be controlled. 



The third, or pupa state is usually a quiet, inactive and 

 perfectly harmless stage. Since many insects winter in this 

 condition we can take advantage of it, and resort in the fall 

 to a general cleaning up and burning of all rubbish, leaves, 

 etc., and to the burning over of stubble and to late plowing. 



The fourth, or adult or imago stage is the perfect insect, 

 such as a butterfly, moth, beetle, fly, etc., and it is in this 

 state only that the eggs are deposited from which a new 

 brood developes. As stated under the second or larva state, 

 most adult insects except grasshoppers and beetles are in 

 themselves harmless to the farm and garden crops ; they de- 

 posit the eggs, however, on the respective plants on which the 

 larvse feed, and in view of this we can take means to prevent 

 such a deposit and hence protect the plant. This is espec- 

 ially true and important in those cases where the larva is a 

 borer and hence can not readily be gotten at in that stage. 

 Hence the necessity of covering up the base of peach trees 

 with straw, cotton seed, ash, etc., to keep the adult from 

 getting at the proper place to deposit her eggs, or of spray- 

 ing apple trees with Paris green or London purple to pre- 

 vent the coddling moth from getting into the apple, or of 



