16 MISC. PUBLICATION 273, U. 8S. DEPT. OF AGRICULTURE 
CONE BEETLES 
Pine cones which dry and wither before they are half grown 
(fig. 5), and either drop to the ground or are retained as blighted 
immature specimens, usually have been killed by the cone beetles, 
Conophthorus spp. (49). 
The adults are small, dark, shining cylindrical beetles, from one- 
sixteenth to five thirty-seconds of an inch in length. They bore into 
the base or supporting stem of the immature pine cones in the spring 
soon after the beginning of the second year’s growth. A small 
tunnel is projected through the axis of the cone, and in this the 
female beetle deposits her eggs. From these hatch small, white, 
curled, legless grubs which feed upon the scales, seeds, and tissues of 
the withering cone. Development to the adult stage is completed 
during the summer within the dead cone, where the beetles usually 
remain over the winter. The damage to the cone crops of ponderosa 
pine, western white pine, and sugar pine is often very severe. In 
some years from 25 to 75 percent of the cones of sugar pine have 
been killed over large areas. In other pines the damage is less 
conspicuous. No method of control seems feasible under forest 
conditions, 
A number of species found in western pines have been described 
by Hopkins and named for their principal host trees. The following 
list gives the species of Conophthorus that may be found in western 
forests: 
Species of Conophthorus Hosts and distribution 
GC. ponderosae Hopk2=- 22s Ponderosa pine, lodgepole pine, and Jeffrey 
pine. Pacific States. 
CU -Scopuloniim Hop =. oe Ponderosa pine. Rocky Mountain region. 
C. lambertianae Hopk-— = Sugar pine and western white pine. 
C. monticolae Hopk] = = Western white pine and ponderosa pine. 
C27@01atie- Hop kee a ee ee Monterey pine. 
C3 CONtOTICE THO Kee eee Lodgepole pine. 
Cmonopiyliag Hopke= = ss Singleleaf pinion pine. 
OS COATS ENO ee eee eee Pinon pine. Colorado, Arizona, and New 
Mexico. 
CAGpCCheCCe CHO pk eas ene ee Apache pine. Arizona. 
CG. fleniis sno pk eee Limber pine. 
CONE MOTHS 
The caterpillars of certain species of moths feed on the bracts, 
scales, and seeds of tender growing cones. Such feeding dwarfs or 
deforms the cones and sometimes causes their death, but more fre- 
quently destroys a large percentage of the seeds without killing the 
cones. The work of certain species is characterized by larval tunnels 
within the cones and an opening at the surface through which resin 
mixed with larval castings exudes. Other caterpillars attack the 
cones and mine through the axis and into the seeds without causing 
resinous masses or deformity of the cones. 
The adults are mostly small inconspicuous moths which are seldom 
noticed. They usually fly early in the spring and deposit their eggs 
on the scales of young cones. The eggs hatch in a few days, and the 
young larvae bore into the cones, where they feed until fall. When 
the caterpillars reach full orowthe they form silken cocoons on the 
surface of the cones, among - the cone scales, or in the pith, in which 
