84 MISC. PUBLICATION 273, U. 8S. DEPT. OF AGRICULTURE 
During the latter part of August the mature caterpillar, which is 
dark green and about one-half inch in length, drops to the ground on 
a silken thread and, after crawling into the mat of old needles, 
spins a loosely woven cocoon in which the winter is passed in the 
pupal stage. The 
adult emerges the 
folowing May or 
June, completing one 
single annual gener- 
ation. The work of 
the lodgepole pine 
needle tier is recog- 
nized by the silk- 
lined tubes, that may 
consist of as many 
as 16 needles webbed 
together, and which, 
as a result of the 
feeding, turn brown 
and clie. 
A. related species, 
Argyrotaeniacitrana 
Fern., feeds on the 
needles of Monterey 
pine in California. 
The spruce bud- 
moth (Zeiraphera 
ratzeburgiana Ratz.) 
is an introduced pest 
that has become 
established in the 
Pacific Northwest. 
The small, lght- 
brown moths, with 
darker diagonal 
markings, and a 
wing expanse of 
about one-half inch, 
lay their eggs on 
spruce needles. Each 
young caterpillar 
crawls into an open- 
ing bud and feeds on 
FicurE 41.—The lodgepole pine needle tier (Hulia pinatu- the Gen der new 
eee eae B, a silk-lined needle tube; necdle S, webbing 
them together to 
form a shelter within which it feeds. Growth is completed late in the 
summer, and the chrysalid is formed in the shelter at the tip of the 
infested twig. The adults emerge late in the summer. There 
appears to be one generation a year. The damage has been fre- 
quently noted on young Sitka spruce trees along the coast of Oregon 
and Washington. In many cases all of the new tips are killed and 
the tree made to branch excessively. | 
