The Aspen Borer and How to Control It. 5 
mains for from 90 to 100 days. It then enters the sap and heartwood, 
where it excavates an oval-shaped longitudinal gallery 6 to 14 inches 
in length, as shown in figure 5. 
The egg scars, whether the eggs hatch or not, are favorite places 
for entrance of difier Reed: borine insects and & fungi which hasten 
the death of such tzees. 
Throughout the forests of the Pikes Peak region many trees have 
died during the last 25 years. The old standing dead trees and those 
Fie, 2.—On Cheyenne Mountain, Colo., aspen which have 
attained a size of from 15 to 23 inches in diameter and 
from 70 to 100 feet in height. 
which have fallen bear evidence of the primary attack of the aspen 
borer in the conspicuous large scars, exit holes, and deformed trunks. 
(Fig. 6.) 
In some localities the standing dead, fallen, and dying trees exceed 
50 per cent of the total stand. A count made on an area of about 2 
acres near Wade, on Cheyenne Mountain, Colo., in an even-aged 
stand of aspen gives the following figures: 
TE eniineRiOtEa LOC sean eee ee hte et 667 
ALA DEI Ola nvanoy UeOs eee c le)! Bee ee ee Se ele ee 260 
ASU CHa! OLS TF CONE Coby sh ayes oI sts (SLO Che SE A Eh 34 
BIH Der Ots CeA CERES: os ea eet | Oe SE, AS ges ee ee 340 
“Sonehelaie 40bb od wuee Se ge SOS ee 33 
Deformed trees, 40 per cent of total. 
