INSECTS AFFECTING GRAINS, GRASSES, FORAGE 83 



and in them transform to pupae. Three or four weeks later 

 the adult beetles shed the pupal skins, but few of them make 

 their way to the surface during the fall, most of them remaining 

 in the pupal cells until the following spring. 



Control. As they resemble the white grubs in life-cycle, so 

 the means of control are similar. By plowing in late summer 

 or early fall and thoroughly harrowing for a month or so, large 

 numbers of the pupa3 and newly transformed beetles will be 

 destroyed. When the wireworms are numerous in restricted 

 areas, as they often are on spots of low moist land, they may be 

 effectually trapped with but little labor by placing under boards 

 bunches of clover poisoned with Paris green. A short rotation 



FIG. 51. A, last segment of Melanotus communis, dorsal view (After 

 Forbes); B, the wheat wireworm, Agriotes mancus a, b, c, d, details 

 of mouth-parts, enlarged; C, caudal segment of the wireworm of Draste- 

 terius elegans; D, caudal segment of the wireworm of Asaphes decoloratus, 

 much enlarged. (-4, C, D, after Forbes; B, after Slingerland.) 



of crops in which land is not allowed to remain in grass for any 

 length of time will prevent their increase. Many remedies have 

 been suggested for these pests, but few of them have proved 

 to have much merit in careful tests. Coating the seed with gas 

 tar, as is done to protect it from crows, has been very widely 

 practiced, and though previous experiments indicated that it could 

 not be relied upon, Dr. H. T. Fernald conducted tests in Massa- 

 chusetts in 1908 and 1909 in which seed coated with gas-tar 

 and then dusted in a bucket of fine dust and Paris green suffi- 

 cient to give the corn a greenish color, was effectively protected, 

 the treatment seeming to act as a repellant, and not affecting 

 the germination of the seed. 



