INSECT ENEMIES OF WESTERN FORESTS AT 
Species of Cinara Hosts and distribution 
GCARSChivarei wWillsSOne=} sa att Ponderosa and other pines. Arizona and 
Colorado. 
C. pseudotsugae Wilson__________ Douglas fir. Oregon. 
ORLOV OG SWee sae Douglas fir. California. 
(Oi ATA OC a ULI as TR Blue spruce. Colorado. 
Ccaudell4 Wilson___-__-.-_____-— Spruce. British Columbia. 
Ceanmenrenae- Galli tate 2 2s eee Engelmann and other spruce. Colorado. 
WreniGed Panzer 22. 22) =. ts Spruce. California. 
Candie Wilson 22 22 Spruce. Washington. 
CR ERT UST OWesee a a ns White fir. Northern California. 
C. pacifica Wilson Pa) hc eek _.._ Lowland white fir. Northern California. 
0. occidentalis Davidson_.________ White fir. Oregon and California. 
CeO Grell WVASON = 3 ee Juniper. Colorado and Idaho, 
Garujapelunus DelG@= 2-22 8 es Aborvitae, cypress, and cedars. California. 
SPRUCE GALL BARK LICE 
Cone-shaped galls which form on the twigs of spruce trees are 
caused by several species of gall and bark lice belonging to the genera 
Adelges and Pineus (1) (formerly called Chermes). These galls fre- 
quently kill the terminals but rarely endanger the life of the trees and 
are of little importance under forest conditions. On seedlings and 
saplings in nursery or plantation, and on ornamental trees in gardens 
and parks, the formation of these galls is of more consequence, since 
they kill the tips of branches and tend to stunt and deform the trees. 
Most of these insects have an alternate host tree upon which they 
appear in a different form. On pines and Douglas fir these alternate 
forms appear as a dirty white wax on the bark or as small tufts of 
cottony wax on the needles. Often these bark lice exude a honey- 
dew upon which a black smut grows, and accumulations of this make 
trees very unsightly. 
In nursery and plantation the gall lice can be controlled by cutting 
and burning the green galls before the insects have emerged in the 
spring, or by spraying the trees early in the spring, when the young 
begin to colonize or. the new growth. For this purpose use a miscible- 
oil spray composed of 5 gallons of miscible oil, 1 quart of 40-percent 
nicotine sulphate, and 200 gallons of water. 
Cooley’s gall louse (Adelges cooleyt Gill.) 1s the species most fre- 
quently responsible for the formation of cone-shaped galls on ter- 
minal twigs of blue spruce, Engelmann spruce (fig. 21), and Sitka 
spruce in the West. Two or more other species do similar damage. 
The galls are from 1 to 2 inches in length, ight green to dark purple, 
and are formed by the growing together of the basal portion of the 
needles so as to form chambers between the base of the needles and 
the stem. These chambers, which are not communicating, usually 
contain from 3 to 30 small wingless insects covered with a white 
waxy coating. These galls turn brown, dry, and hard on the trees 
after the insects have escaped, and they may persist for many years. 
The alternate host is Douglas fir, on which these gall lice appear 
as small cottony tufts on the underside of the needles. Their feeding 
punctures cause the needles to turn yellow in spots. Sometimes the 
damage is so severe as to cause a browning and premature shedding 
of the foliage. 
The seasonal history is very complicated. The form found on the 
Douglas fir needles during the winter represents hibernating females 
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