^62 INSECTS INJURIOUS TO STAPLE CROPS. 



The Beet Army-worm {Lajihygma fiavimaculata Harr.). 



''This caterpillar, which replaces the Grass-worm 

 (L. friigiperda — see page 84) in the Western States, differs 

 from it by its more decidedly mottled ground-color, by a 

 row 01 white dots at the lower margin of the lateral dark 

 band, and by the yellower color of the light stripes. It is 

 an interesting fact that while the preceding species was 

 doing serious, unusual, and wide-extended injuries in the 

 Eastern and Southern States (1899), the present one was 

 similarly abundant in Colorado, where, besides destroying 

 many kinds of weeds and grasses, it completely defoliated 

 thousands of acres of sugar-beets. In some cases where 

 the foliage of the beet did not furnish it sufficient food, 

 the root was attacked and the upper surface was completely 

 gnawed away. Late plantings of course suffered most 

 severely, especially when surrounded by newly broken 

 ground. The weeds most generally eaten were pigweed, 

 saltweed, wild sunflower, and cleome. Potato-, pea-, and 

 apple-leaves were also devoured. These injuries occurred 

 about the middle of August, at which time the larvae and 

 pupa3 were abundant, and a few moths laden with eggs 

 were noticed." 



This species evidently hibernates as a moth, and at 

 least two broods of larvae may be looked for each year, the 

 first about June and the second in August. The species 

 has been reported thus far from Colorado and California, 

 but it doubtless has a more extended range in the moun- 

 tain region of the far West. 



*' Prof. Gillette's field-experiments showed that it could 



