BULLETIN 111. U. S. DEPAKIMEXI OF AGKICULTrEE. 
SECONDARY INJURY BY FIRE. 
About one-half of 1 per cent of the trees infested by Yesparnima 
sequoia is killed. In ease of a slight surface fire in places where, out- 
side of humus, no litter covers the ground, all the infested trees which 
are not killed outright come through it with the bark on the sides 
where the pitch exudation is located literally cooked, and for the 
balance of their existence they display the "fire wounds " (fig. 5 . of 
which the pitch moth was the primary cause. They remain green 
but add little to their size annually. Subsequent fires fell them 
Fig. 5.— Fire wounds on pine rree injured by rhe Sequoia pitch moth. (Original.) 
readily, and their burning injures and kills perfectly healthy trees, 
which would otherwise have remained unscathed. 
There is abundant proof in the area under discussion that unat- 
tached trees, on ground not littered with fallen timber, pass through 
surface fires with but slight injury. Thousands of such trees are 
mingled with as many which display "•fire wounds " and the tunnel of 
Yesparnima burned indelibly into the base of the latter, thus explain- 
ing why it is that some trees are half burned while others, under the 
same conditions and at the same place, have escaped with scarcely a 
scar. 
