372 Kansas State Board of Agriculture. 



Habits and Life History. 



These insects pass the winter chiefly as young larvae in earthen cells 

 in the clover or alfalfa sod. Occasionally a few of the beetles may 

 hibernate and survive the winter, but it is doubtful whether the hibernat- 

 ing beetles lay any eggs in the spring. About the first of June the 

 wintering larvae, which have been working on the roots of clover and 

 alfalfa, begin to pass into the pupal stage, and from the middle of June 

 on through July, August and September the beetles are common in the 

 field, where they may be found cutting out the U-shaped patches from 

 the margin of the leaves. (Fig. 317.) The female beetles probably lay 

 most of their eggs in September. The eggs are yellowish-white at first, 

 turning greenish, and becoming black in two or three days. The young 

 larvae work at the bases of the stems or the bases of the roots. Most of 

 the injury is done by the larvae working on the roots. Some of them 

 may bite out the roots at the crown, causing the plant to wilt. By late 

 fall they are from a third to half grown, and then enter the sod to 

 hibernate in earthen cells. There is only one generation each year. 



Methods of Control. 



The cutting of the hay crop has little or no effect in controlling this 

 insect. The larvae continue to feed on the roots, and the beetles on the 

 leaves as soon as they appear. 



Probably the most effective method of control would be late fall and 

 early spring disking of the alfalfa. This will not only break open many 

 of the earthen cells and expose the larvae to the weather, but it will also 

 crush many of them. 



WHITE GRUBS. 



(Lachnosterna sp.) 



Thick, fleshy, white grubs, about one and one-half inches long when full 

 grown; dark-brown head and mouth parts; three pairs of legs, curved 

 body, heaviest at rear end; devouring the roots of the alfalfa plants 

 and causing dead patches in the field. 



Life History. 



The parent of the white grub is the common blundering May beetle or 

 June bug that flies about lights at night and lands against the screens 

 with a thump, or if it succeeds in entering, flies about the room with a 

 loud buzz and strikes the walls and ceiling with a thump. The beetles 

 emerge from the wintering pupae in the soil in May and June and the 

 females deposit their eggs in grass lands, meadows, alfalfa and clover 

 fields. The grubs hatching from these eggs live in soil almost three 

 years before reaching maturity, and thus the adult beetle rarely emerges 

 until three years after the egg from which it develops was deposited. 

 (Fig. 318.) However, different individuals complete growth each year, 

 and thus the June bug is common every year. The grubs consume the 

 roots of the alfalfa plants, thereby depriving the plant of a part of the 

 normal food supply, checking its growth, and many times completely 

 killing it. 



