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Webworms Injurious to Cereal and Forage Crops. 18 
instance practically all the pastures in several counties were com- 
pletely stripped of every green blade of grass, appearing in late May 
as bare and brown as is usually the case in December. Most of such 
fields produced very little growth during the rest of the season and 
in many of them much of the grass died outright. While no such 
severe devastation has been observed since that time, it illustrates 
the severe injury of which any of these common grass-feeding web- 
werms are capable of when all the conditions favor them. 
The black-headed sod webworm has only one generation each year. 
The eggs are laid in August and September and soon hatch. The 
tiny worms feed for a few days until cold weather overtakes them 
and then remain quietly within their little silken galleries through- 
out the winter. With the opening of spring they become active and 
feed vigorously until they are fully grown, which usually is about 
the first of June. They then con- 
struct cocoons in the earth just be- 
neath the surface and le in them 
quietly until August, when they 
change to pup and emerge a 
week or ten days later as moths. 
The moth (fig. 8) is rather 
large, clay-yellow, flecked with 
numerous chocolate-brown scales 
and with gold fringes on the Fie. 11.—Adult of blue-grass webworm. 
: 5 : About three times natural size. 
wings. It is conspicuous when 
flying and often very abundant. This is probably the most widely 
distributed of all the sod webworms, as it occurs from Texas to and 
throughout southern Canada and from Maine to California. 
LEATHER-COLORED SOD WEBWORM.‘ 
The leather-colored sod webworm is one of the largest of the sod 
webworms, the mature worm reaching a length of about an inch and 
the moth spreading about an inch and a quarter. The moth is yel- 
lowish gray and the larva or worm dark leather-brown or dingy yel- 
low clouded with brown. This species occurs entirely across the con- 
tinent in southern Canada, south to Tennessee east of the Mississippi, 
and almost to the Mexican border in New Mexico. It is abundant 
and destructive over an area extending from Ohio to Iowa. 
There are two or three generations each year. Only small larve 
live throughout the winter. In the fall, usually in October, each 
tiny larva spins a thin but tough, white, silken case closely about 
itself and remains tightly coiled in this case until April, when it 
again begins to feed. These overwintering larve complete their 
© Crambus trisectus Walk. 
