second-year red pine cones, but also attacks current-year red pine shoots and 
occasionally second-year jack pine cones. It is also found in cones of Virginia pine 
in West Virginia (/356). The adult is shiny black, with sparse, short fine hairs and 
is about 3 to 3.5 mm long (758). 
Seasonal activity begins in May when the overwintering adults emerge and attack 
current-year shoots and second-year cones of red pine. The adults feed for a few 
weeks and then attack cones for oviposition purposes. Cones are entered by females 
near the petiole on the underside, often forming an open groove at the cone base. 
The tunnel is extended in the pith to the end of the cone. Eggs are deposited singly 
in niches along the sides of the tunnel. After oviposition is completed, the female 
returns to the base, fills the base of the tunnel with a plug of resin and debris, then 
vacates the cone. Infested cones soon wither, harden, turn brown, and occasionally 
drop from the tree. The larvae feed on seeds and scales in the cone and pupate in 
frass-lined cells which often are near the base. During late summer, new adults 
emerge either through the plugs in the bases of the tunnels or through the top or 
sides of the cones. Soon after emergence they bore into current-year red pine shoots 
and tunnel forward through the pith into vegetative buds where they spend the 
winter. There is one generation per year. Weakened at point of beetle entry, pine 
shoots soon break off and fall to the ground. Damage by C. resinosae is often 
severe enough to make the commercial collection of red pine seed impractical or 
impossible. Prescribed burning is recommended as a control technique for the red 
pine cone beetle (855). 
Conophthorus banksianae McPherson, the jack pine tip beetle, a species 
closely related to C. resinosae, also occurs in the Lake States and southern Canada. 
It breeds in the shoots of jack pine. The adults bore into the shoots about 25 mm 
below the bud then tunnel toward the bud, either to feed or to deposit their eggs. 
Ovipositing lasts from late May into mid-July. Winter is spent in infested buds, and 
there are two generations per year. Infested terminals are often killed, leading to 
multiple branching and flat-topping of infested trees. Damage to natural jack pine 
reproduction and in jack pine plantations is often severe. 
Wood-Boring Beetles 
Xylophagus Scolytidae 
Genera of Scolytidae that feed on wood occur in both subfamilies (Hylesininae 
and Scolytinae). Xylophagus scolytids in eastern North America bore into mori- 
bund to dry dead twigs on various hardwood species. Mining by adults and larvae 
deeply scores the surface of the wood or is entirely within the wood. A rapid change 
in color and texture of the wood near the tunnels suggests that micro-organisms 
introduced by the beetles are important in nutrition of the beetles. Species with this 
feeding habit cause no economic loss. 
Genera included here under this feeding habit include Hypothenemus, 
Hylocurus, Micracis, Micracisella, and Thysanoes. A few species of Pityophthorus 
may be truly xylophagus but this genus is grouped with the bark beetles because 
tunneling in the wood of twigs by some species appears to be incidental to their 
feeding in the bark and pith. 
The genus Micracis contains a number of species that breed in the wood or pith 
of their hosts. Adults are similar to those of the genus Hylocurus but differ in having 
the first joint of the antennae flattened and ornamented with long hairs. 
Micracis swainei Blackman, a widely distributed species in the South and 
Southwest, breeds in poplar shoots and in dead and dying twigs of redbud and 
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