32 



clover, violets and some other ornamental plants. It has been noticed 

 attacking grasses and oats, but does not appear to resort to these 

 plants when more choice food is at hand. 



THE WESTERN ARMY CUTWORM. 



( ChorizagrotiH agrestis Grote. ) 



In 1897 this cutworm, which had hitherto led an unpretentious exist- 

 ence in the Missoula Valley, Montana, developed in great numbers, and 

 a serious outbreak followed. According to the account given by Dr. 



E. V. Wilcox (Bui. 17, Mon- 

 tana Agl. Exp. Sta., 1898), 

 this visitation resembled that 

 of the common arm}' worm, 

 and the list of observed food 

 plants shows that it can 

 be a very serious vegetable 

 pest, since, besides beets, it 

 attacks cabbage, horse-rad- 

 ish, radish, nmstard, turnip, 

 pea, tomato, potato, onion, 

 celer}', rhubarb, corn, cereals, 

 grasses, clover and other for- 

 age crops, forest and fruit 

 trees, and bush fruits. 



This cutworm (fig. 2S) is of 

 the ordinary type, and attains 

 a length of 2 inches when 

 mature. Its body is nearly smooth, only a few short hairs l^eing 

 observable. The color varies from pale green to dark brown. xVlong 

 the sides there are alternating longitudinal light and dark bands. 

 The moth is brown with gray markings, has a wing expanse of about 

 li inches, and is quite variable.'^' 



The recorded distribution comprises Kansas, Nebraska, Texas, New 

 Mexico, Arizona, Colorado, Montana, and California. 



Although the injuries committed in 1897 have not to our knowledge 

 been duplicated, reports have reached us of the occurrence of great 

 numbers of the species in widely separated localities, the moths 

 flying about in such numbers as to become annoying pests in dwell- 

 ings. Such reports were received from Missouri in 1902, and from 

 Arizona and Colorado in 1903. In Montana a "wild sunflower" 

 [Bcdsamorrhiza sagittata) and avens {Geum trifiorxuri) are favorite 

 food plants, but in other localities it seems probable that the natural 



«This speciea is so often accompanied bj- two related forms, more particularly by 

 Chorizagrotis introferens Grote, as to give rise to the supposition that all are colora- 

 tional varieties of the same species, the truth of which will probably be established 

 by rearing from selected females. 



Fig. 28. — Chorizagrotis agrestis: moth above; larva, dor- 

 sal view, in center; larva, ventral view, below — some- 

 what enlarged (original, Division of Entomology). 



