INSECTS AND THEIR REMEDIES. 99 



the earth, he may limit the destruction of property they 

 cause, and it is to the farmer's interest, and is his duty, 

 to wage a united war against them, knowing no to- 

 morrow in its prosecution, but killing and destroying 

 wherever and whenever possible, and employing every 

 means in his power. Individual effort can avail little, 

 and concerted action is necessary. 



In our climate, insects generally have two broods in a 

 season. Most of those which survive the winter in their 

 perfect state are fertilized females, and all insects, if left 

 unmolested early in the season, will propagate their spe- 

 cies, and the second brood will outnumber the first a 

 hundred or a thousand-fold. 



While recommending a determined crusade against all 

 insect pests, I would, from the same motive, protest 

 against the pernicious habit, so common all over the 

 cc untry, of indiscriminately taking the life of the lower 

 animals inhabiting the fields and woods; for the reason, 

 that many reptiles, the toads and moles, are our innocent 

 friends and aids. There are but very few venomous 

 snakes, and the larger kinds, which are not insectivorous, 

 destroy numbers of field rats and mice. 



PARASITIC INSECTS. 



We are occasionally subject to the visitation of an in- 

 sect in vast numbers; but these generally bring with 

 them the cause of their own limitation, or there would 

 be no equilibrium in nature. Swarms of parasitic insects, 

 finding an increased food supply, follow in their wake, 

 and the farmer, aroused from his apathy, by finding his 

 entire crops, and not merely a portion thereof, endan- 

 gered, resorts to all sorts of devices to save them. He 

 dusts and sprinkles poisons, he digs circumscribing 

 ditches with upright sides and pitfalls, and applies the 

 torch and burning petroleum. 



Previous to 1862, the European cabbage butterfly 



