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forest and shade-tree insects 
EOREST TENT CATERPILLAR ( Malacosoma disstria Hbn.) 
Vermont. H. L. Bailey (July 25): Much evidence of disease among larvae 
in Orange and Windsor Counties. Very little complete defoliation, 
But thinning of foliage in the upper White River Valley, central 
Vermont, and at Grafton and Chester, southeastern Vermont. 
Washington. R. L. Furniss (June 26): During May larvae completely de- 
foliated extensive stands of willow along the north hank of the 
Columbia River, in Cowlitz County. Appreciable defoliation notice- 
able on May 12. By May 23 many of the willows completely defoliated 
and immature caterpillars migrating in search of food. By June 15 
a very large part of the population had died of starvation , and 
the remaining caterpillars were, beginning to spin cocoons. Para- 
sitization by tachinids comparatively low. 
Oregon. R. L. Furniss (June 26 ): Very small larvae found on willows 
along the Coquille River near Coquille, Coos County, on May 20. 
While moderately abundant , it was evident that defoliation would be 
much less severe than in 1932, when willows and orchard trees in 
this vicinity were completely stripped. Extensive defoliation of 
several species of ceanothus by tent cater illars ( Malacosoma sp.) 
occurred this year in Josephine County, in tho vicinity of Grants 
Pass. Infestation by this species slowly building up in this area 
since 1937* On May 19 a few mature larvae found, but most of them 
still actively feeding, and some had not left their tents. A high 
percentage of parasitization by tachinids was noted. 
WESTERN TENT CATERPILLAR ( Ma,lacosoma pluvial is Dyar) 
Washington. R. L. Furniss (June 2b): An outbreak occurred in the Puget 
Sound Basin. Hea.vy defoliation of alder noted in Piorce, King, 
Snohomish, and Skagit Counties. Other plants defoliated were apple, 
cherry (wild and cultivated), pear, plum, walnut, and wild rose. 
Considerable defoliation noted on Ma.y 11 on Whidby Island. On June 
21 feeding nearly complete at Fairfax, and cocoon formation was 
beginning. 
Oregon. R. L. Furniss (Juno 26): Light defoliation of orchard trees and 
wild rose noted near Lebanon, Linn County, on May 17, when larvae had 
reached maturity and wore beginning to spin cocoons. In the coast 
counties moderately abundant on alder. On May 20 larvae were small 
and still congregated on the tents. 
BLUE-SIDED TENT CATERPILLAR ( Malacosoma constricta Stretch) 
Oregon. R. L. Furniss (June 26): On May 19 moderate defoliation of oaks 
( Quercus gariyana and Q. kolloggi) noted near Grants Pass, Josephine 
County. At that time larvae had reached maturity. A high percentage 
parasitized by tachinids. 
