Pests and Diseases 191 



species having a slightly different appearance. They 

 work most vigorously in spring about the time the garden 

 is coming up. They attack practically all crops, doing 

 most damage by cutting off the young plants just as they 

 are coming through the ground. When they are present 

 in large numbers and take on the army habit, almost 

 everything in their way is destroyed. They feed at night 

 and hide during the day. 



The moths lay eggs in July and August in fields that 

 have grown up to weeds. The eggs hatch early in the fall 

 and the young worms feed a few weeks before hibernat- 

 ing in the soil. In the spring they come out with a full- 

 grown appetite ready to eat almost anything. If poisoned 

 bran, clover, or alfalfa is spread over the field just before 

 the young beets come up, the worms will devour sufficient 

 of the bait to be killed before injury is done to the crop. 

 Arsenate of lead is used for poison. In large fields thor- 

 ough cultivation in the late summer and keeping the 

 land free from weeds, together with deep fall plowing and 

 early spring cultivation, help to control the pest. 



White grubs (Lachnosterna spp.). 



The larvae of several species of June bugs or May beetles 

 pass under the name of white grubs. As high as 15 per 

 cent of the fields of beets in some districts has been re- 

 ported destroyed by this pest, although it is not usually 

 considered to be serious. Its action is worse in crops 

 following sod, since grass land is its natural breeding place. 

 Its life history is similar to that of the wireworms dis- 

 cussed below, about two years being required for the 

 grub to complete its cycle. 



