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wheat heavily fertilized before sowing, with barn-yard manure — al- 

 most the only wheat in that neighborhood— was very vigorously at- 

 tacked in spring by the chinch bug, much of it being badly dam- 

 aged by the adults of the hibernating generation before tlriey had 

 even laid their eggs. Nothwithstanding this injury, and that by 

 the much more abundant generation following, this plot yielded, 

 according to a report made to me August 4, at the rate of 20.8 

 bushels per acre, ^4 pounds to the bushel ; while the portion of 

 it treated in spring with special fertilizers* yielded at the rate of 

 24 bushels per acre, 62 pounds to the bushel. The ususal aver- 

 age yield of this region does not exceed 18 bushels. It is scarcely 

 possible that this field could have yielded more than ten bushels 

 per acre if left unfertilized. The effect of the first " application of 

 manure was, therefore, to about double the crop; and that of the 

 second, to further increase this yield by some twenty-eight per 

 cent. 



7. Fall ploiomg, and heavy rolling after fhe seed is sown. This 

 measure is based upon the fact that the female chinch bug seeks 

 the roots of grain in spring upon which to lay her eggs, and 

 can penetrate compact soil less readily than that recently plowed. 

 As the eggs are very frequently and freely laid, however, upon 

 the lower part of the plant above the earth, this measure j)robably 

 cannot have any very important effect. 



8. The use of surplus seed. This serves a double purpose; that 

 of shading the ground, as mentioned above, and that of supplying 

 an excess of vegetation, some of which may be sacrificed to the 

 bugs without serious diminution of the yield. 



9. Early pkmting of crops exposed to chinch-hug attack (ex- 

 cepting corn). As the principal damage is done by the young of 

 the spring generation, and as these do not ordinarily begin to 

 hatch until the middle of May and are most destructive late in 

 June, early planting may often so advance the crop as to get it 

 practically out of their way. This applies as well, of course, to 

 winter grain as to the spring varieties. 



10. Late planting of corn. Corn should be planted late enough 

 to make it certain that the hibernating adults have all left their 

 winter quarters and established themselves in grain fields for re- 

 production; otherwise the crop may be infested by this first gen- 

 eration as well as by the second. 



11. Mixture of seed, to repel or destroy the insect. The sow- 

 ing of clover in spring on winter wheat is largely practiced in 

 Southern Illinois, and with unquestionably good effect, provided that 

 the clover grows freely enough to shade the ground by the time 

 the young chinch bug gets fairly under way. Frequently, how- 

 ever, in that latitude, clover makes too slow and slight a start to 

 effect this purpose. 



•One hundred poniids each, per acre, ofnllrate of8oda, superphosphates, and sulphate of pot- 



