Description and Seasonal History 



The life history of the armyworm has not been traced thoroughly, for it 

 varies widely in different parts of the country. It seems to have six broods in 

 the South and two in New England. It appears to winter here as a partly 

 grown caterpillar, but probably survives only our mildest winters. The worms 

 mature in the spring and go an inch or more into the soil to pupate. The 

 pupal stage lasts two weeks or longer, and the moths emerge from the ground 

 and fly at night, laying eggs for the next brood. These hatch in a week to 

 ten days. The worms mature in about a month, go into the ground, pupate late in 

 July, and become moths as described for the first brood. The moths appear in 

 August and lay their eggs, and the caterpillars from these hibernate. 



It will be seen that the worms feed in the fall and early spring in one brood 

 and in the summer m another. The latter only is destructive. 



THE EGG 



The eggs are laid in rows or masses of ten to fifty, mostly in the leaf sheaths 

 of grasses and grams or on stubble or straw, usually in moist or shaded spots, and 

 covered with a gelatinous substance. Each moth commonly lays live to six hundred. 



THE WORM 



The young worms loop like spanworms and spin down on silken threads 

 but soon lose these habits. The maturing caterpillar (Plate Two, figs, la and 

 lb) is smooth and rather dark. A broad dark brown stripe runs the length 

 of the back and usually is divided by a broken pale line running along its 

 middle. At each side of the dark back stripe is a narrower reddish yellow one. 

 then a dark one, and lastly another reddish yellow one. These colors vary some- 

 what. The stripes are separated by pale yellow lines. The under side of the 

 body is pale greenish brown. The spiracles are black. Each proleg of the four 

 anterior pairs has a noticeable deep brown stripe across the middle of its outer 

 side. The head is yellowish brown with a color network of darker brown. The 

 mature worm is about an inch and a half long. 



THE PUPA 



This is reddish or chestnut brown at first, becoming blackish before the 

 moth emerges. 



THE MOTH 



Swarms of the moths often appear about street lights shortly before an out' 

 break of the worms. Cranberry men sometimes may be warned by this and 

 should know the moth at sight. It usually spreads about an inch and five- 

 eighths and is plain light brown (Plate One, fig. 12). Each forewing has a 

 white speck near the center of the upper surface and a dark shade running back 

 obliquely from the outer angle. 



The moths live on the nectar of flowers and the honeydew of certain insects, 

 and sometimes many may be caught with sweet baits at night. As they rarely 

 lay eggs near where they have developed and often fly many miles before 

 doing so, there seldom are two outbreaks a year in any one locality. 



Treatment 



FLOODING 



On hogs that cannot be reflooded. — Consult the Bureau of Entomology of 

 the United States Department of Agriculture as to the probability of an army- 

 worm invasion. If an outbreak is predicted, do not hold the winter water after 

 May 20. 



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