114 INSECT PESTS OF FARM, GARDEN AND ORCHARD 



The Army Worm* 



Almost every year some locality reports serious injury to 

 crops by armies of caterpillars, which have not been previously 

 known for many years. This being the case the farmers are 

 at a loss to combat them, and by the time information has been 

 secured the pests have completed the damage. The Army 

 Worm occurs throughout the United States east of the Rocky 

 Mountains and lives in low, rank growths of grass, which form 

 the normal breeding-grounds. When from an abundance of 

 such food, or through failure of the parasites to prevent their 



increase, the caterpillars be- 

 come overabundant, they as- 

 sume the army habit and 

 march en masse, consuming 

 all in their path. 



The next year their natural 

 enemies will usually have them 

 under control again and there 

 will be but little damage, and 

 then they will not be observed 

 as injurious for a series of 



FIG. 83. Army-worm moth (Leucanm y ears , though the moths arc 



unipuncta), pupa, and eggs in natural always fairly common, 

 position in a grass-leaf . Natural size. T ... TT . . 



(After Comstock.) Ll f e History. In the North 



the moths appear early in June 



and the females lay the small yellowish eggs in rows of from 

 ten to fifty in the unfolded bases of the grass leaves, covering 

 them with a thin layer of glue. Over seven hundred may be 

 deposited by one female, so that when the young caterpillars 

 hatch in about ten days, the progeny of a few moths might 

 form a quite destructive army. The worms usually feed entirely 

 at night, and thus whole fields will sometimes be ruined before 

 they are discovered, though a few generally feed by day, as 

 they all do in cloudy weather. The leaves and stalks of grains 



* Leucania unipuncta Haworth. Family Noctuidce. 



