of the twig containing the cell may have been girdled previously. 
Occasionally dogwoods and elms are seriously damaged. The cut- 
ting off and burning of infested twigs might be helpful in control. 
Oberea schaumi LeC. occurs in southern Canada and south in 
the Eastern States to the Gulf Coast. It breeds in poplar. Adults 
are about 14 mm. long; the thorax is yellowish to black and is 
marked by four round, smooth spots. The elytra are either yellow- 
ish or black. Eggs are laid in the stems and branches of suckers 
and seedlings; also in the twigs of saplings, poles, and large trees. 
The larvae feed near the pith, excavating tunnels up to 6 inches 
long, and boring holes to the outside for the expulsion of frass. 
Black, necrotic areas develop around these holes. Infested twigs 
die but are usually not sufficiently weakened to permit wind 
breakage. 
Oberea myops Hald., the rhododendron stem borer, breeds in 
rhododendron, azalea, and laurel. The adult is pale yellow and 
about 12 to 15 mm. long. There are two black spots on the thorax 
and the elytral margins are dark. Eggs are deposited in the bark 
of twigs between two girdles about one-half inch apart. The larva 
bores down the twig, to and into the stem, and on down to the 
ground. Here, it cuts off the stem, and then bores into the roots. 
Frass is expelled through holes along the stem and at the ground 
line. This species is frequently a serious pest in ornamental plant- 
ings of rhododendron. Cutting off and burning of infested twigs 
as soon as they are noticed is recommended. 
Oberea ocellata Hald., the sumac stem borer, occasionally causes 
serlous injury in sumac plantings. Adults are about 13 to 15 mm. 
long. The head and underside of the body are red; the thorax is 
red with two black spots on the disk; and the elytra are black. 
The female girdles the tip of the plant and then lays an egg just 
below the girdle. The larva bores down the stem through the pith 
to the roots. Here, it proceeds to construct long tunnels and to 
feed for two seasons. During the fall of the second year, it cuts 
the plant off near the ground and plugs the stub with a wad of 
frass. Below this plug, pupation occurs the following spring. 
Oberea ruficollis (F.) breeds in the stems and roots of sassa- 
fras. Adults are pale reddish-yellow and about 18 to 20 mm. long. 
The antennae, tibia, and tarsi are black and the elytra are densely 
clothed with fine gray hairs. The feeding habits of the larvae are 
similar to those of O. ocellata except that they seldom cut off stems 
near the ground. Infested plants usually survive but may be badly 
deformed. 
Other species of Oberea sometimes encountered are: O. pallida 
Casey—in alder in Pennsylvania; O. ulmicola Chitt.—in the 
branches of oak, elm, hickory, dogwood, and black cherry in Ohio 
and Pennsylvania; and O. ferruginea Casey—in willow canes. 
The genus Oncideres Serville contains several species, the fe- 
males of which deposit their eggs in previously girdled terminals, 
twigs, or small branches of large trees, or in the stems of seed- 
lings or sprouts. The girdled portions soon die and most of them 
fall to the ground. The larvae feed in the wood of this fallen 
material until the middle of the following summer, loosely filling 
their mines with frass. Pupation occurs in a cell formed by wall- 
ing off a portion of the mine with fibrous frass. The adults appear 
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