190 The Sugar-Beet in America 



Sugar-beet webworm (Loxostege sp.). 



These insects were introduced into this country before 

 1869, when they were observed in Utah, having probably 

 come to the Pacific coast from the Orient. It is an in- 

 habitant of Western and Central Europe and Northern 

 Asia. Its wild food plant is pigweed (Amaranthus) and 

 injury is greater to beets when this weed is allowed to 

 grow abundantly. 



The worms spin webs over the leaves of the beet and 

 eat out the portions between the veins. The larva is an 

 inch long when full grown, brownish in color, with a 

 narrow dark stripe edged with white down the middle of 

 the back, and a light stripe along each side. Small dots 

 cover the surface of its body. 



The worms burrow into the ground in the fall and spend 

 the winter in white silken cocoons which they spin around 

 themselves. In the spring the moth comes out and lays 

 eggs on the leaves of pigweed and alfalfa. A second gen- 

 eration comes in July in some regions and a third in August. 

 The last brood is likely to do most injury to sugar-beets. 



Control measures consist of poisoning and late fall 

 plowing, which breaks up their winter cells in the soil. 

 Arsenate of lead is sprayed on the beet leaves. Since the 

 worms destroy the plants rapidly, the poison must be put 

 on as soon as the injury is observed. 



Cutworms (Noctuidae). 



Every gardener is familiar with the work of this group 

 of insects. The several species going under the name 

 of cutworms are the larvae of night-flying moths. The 

 worms are smooth and of a mottled brown color, the 



