Last spring while visiting my older brother in North Carolina, I commented on what a ratty looking Pecan Tree was in his front yard. Malformed and bristling with small dead branches and twigs, it looked more like a porcupine than a tree. Recently he called to say that his forestry extension agent attributed the ratty appearance to the "Twig Girdler". I did a little research (primarily through my county forester) and learned that there are at least 4 twig girdlers differing primarily in geographic location and preferred hosts. The most important eastern member is "Oncideres cingulata cingulata" which infects a number of species including Hickory, Oak, Poplar, Basswood, and other hardwoods. Oncideres cingulata texanus is probably the critter that infected my brother's tree, as its preferred host is Pecan in the south.
The "Twig Girdler", however, is not the culprit littering our New England lawns this summer with the small leafy branches of Red Oaks. Rather, this is being caused by the "Twig Pruner", which will be described next month in Splendid Splinters.
But getting back to the "Twig Girdler", the full grown larvae are about 18mm long with adult girdlers measuring 15mm and grayish brown in color with fine golden hairs on the front of its head. The adults emerge in late summer and feed on the bark and tips of its host, girdling and severing dozens of branches in heavily infected trees. Because leaves die off but the branches hold on for extended periods, the tree assumes a shabby appearance. The best way to control the pest is to gather and burn the infected twigs and branches during the fall and winter.