Eburia quadrigeminata (Say), the ivory-marked beetle, occurs throughout the 
Eastern United States and breeds in the dry heartwood of various hardwoods, 
including oak, hickory, ash, maple, honeylocust, elm, chestnut, and baldcypress. 
Adults are light brown, with pairs of ivory spots at the base and middle of each 
elytron, and are from 12 to 24 mm long. The larvae are wedge shaped, have tough, 
shiny skins, and are sparsely clothed with golden hairs. Mature oaks having 
catfaces or scars through which the larvae can gain access to the heartwood are 
often badly damaged. Seasoned lumber is also subject to occasional attack. The 
normal life cycle appears to be 2 years, but it may be considerably longer. There are 
records of adults emerging from flooring, doorsills, and furniture 25 years after 
they were placed in use. 
The twig pruner, Elaphidionoides villosus (F.) occurs throughout the Eastern 
United States. It breeds in the twigs and branches of living hardwoods such as the 
oaks, hickory, maple, locust, hackberry, walnut, elm, sweetgum, and pecan. Adults 
are slender, elongate, brown, and are from 11 to 18 mm long. The dorsal surface is 
clothed with irregular patches of fine gray hairs. There are spines on the first few 
joints of the antennae, and the tips of the elytra are notched and bispinose. 
Eggs are deposited in slits in the bark at leaf axils near the tips of twigs and small 
branches in late spring. Young larvae feed beneath the bark, often consuming much 
of the wood toward the base of the twig. Older larvae bore down the center of the 
stem toward the base until late in the summer. Then they sever the branch by 
making several concentric circular cuts from the center outward to, but not includ- 
ing, the thin bark (fig. 135). These branches, from 0.5 to 5 cm in diameter, break 
and fall to the ground with the larvae in them. The ground under heavily infested 
trees may be literally covered with these fallen twigs and branches. The larva 
returns up through the fallen branch and forms a cell between wads of fibrous frass 
where it pupates in the spring, or in the fall. There appears to be one generation per 
year. Heavily infested trees may be seriously damaged but are seldom killed. Shade 
and park trees may be so severely pruned that they lose much of their esthetic value. 
The presence of numerous dead twigs and branches hanging in the crown also 
detracts from their appearance. Collecting and burning infested twigs and branches 
in the spring before the adults emerge should be helpful in control. 
F-504092 
Figure 135.—Larva of the twig pruner, Elaphidionoides 
villosus, in an oak twig. Note ends of severed twigs. 
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