282 MISC. PUBLICATION 657, U. S. DEPT. OF AGRICULTURE 
annual reduction in the value of white pine lumber due to knottiness 
and crookedness from the attacks of this insect is enormous, and many 
trees are so completely ruined as not to be fit for sawlogs. Two species 
of Hylobius are also of great importance in young pine stands, 
The adult white-pine ‘weevil (Pissodes strobi ( Pec k)) is a somewhat 
elongate, brownish snout beetle, from 4 to 6 se long and is marked 
irregularly with groups of brown and white scales (fig. 59). The 
curved snout, as long as the prothorax, is one of its ate striking char- 
acters. The pearly white eggs, about 1 mm. long, are usually laid 
singly, but occasionally in groups of two or three. The larvae are 
white and footless, and when full grown are shehtly longer than the 
adult weevil. The pupa is mostly creamy white with the mandibles 
and eyes light brown. The length is the same as in the adult stage. 
FIGURE 59.—The white-pine weevil (Pissodes strobi) : A, Adult (smaller figure 
is hatural size) : B, pupa; C, larva (hair line shows actual length). 
This species occurs over the entire range of the eastern white pine, 
which is its most common host. In addition it frequently attacks 
Norway spruce. Attacks are common on jack pine, pitch pine, Japa- 
nese red pine, western white pine, limber pine, foxtail pine, Scotch 
pine, and red spruce, but occur only occasionally on western yellow 
pine, mugho pine, or black spruce, and, according to MacAloney (279), 
are rare on red pine, Himalayan blue pine, blue spruce, white spruce, 
and Douglas-fir. 
The winter is passed in the adult stage in the litter, and activity is 
resumed, depending on locality and altitude, from March to May. 
The eggs, which are placed in small punctures in the bark of the 
leader, hatch in a week to 10 days, and the grubs, boring downward, 
feed on the inner bark as they girdle and kill the shoot. By August 
of the same year, the larvae become full grown, change to the pupal 
stage, and then to adult weevils. Spread to new areas is by flight. 
The following spring the first evidence of attack is the appearance of 
tiny elistening droplets of resin on the preceding year’s growth, 
exuding from holes made by the adult weevils in feeding or “laying 
