INSECT ENEMIES OF WESTERN FORESTS 83 
The adult needle tier is a small brownish-gray moth with darker 
patches and bands on the forewings and a wing expanse of about - 
one-half inch. Eggs are laid during the latter” part of June and 
early in July in groups of 2 to 30, with an average of about 10 per 
cluster, on the concave side of lodgepole pine needles. These eggs 
hatch in 7 to 10 days, and the young larvae crawl over the foliage 
until needles satisfactory for their attack are found—usually those 
of the current year’s growth. Each larva then enters a needle by 
FicureE 40.—The sugai pine tortrix (Tortrix lambertianae) and its damage to sugar 
pine terminals. 
biting a circular hole near the tip and spends from 2 to 3 weeks in 
feeding on the interior tissues. The inside of the mined_ needle 
is lined with a papery, white, closely woven web to form a tube. At 
an early period in the growth of the larva or when it becomes too 
large for the mined needle, several other needles are drawn to it and 
bound together so as to form a new and larger tube (fig. 41, B). 
This tube is also lined with a papery white web and has an opening 
at each end, that allows the insect to leave quickly when disturbed. 
Often a caterpillar will abandon one tube and form a new one. Feed- 
ing takes place within the tube, and as the caterpillar becomes larger 
the tube is extended farther down the needles, often to the base. 
