Poplar Twig Borer – Oberea delongi
Poplar Twig Borer (Oberea delongi)
Latin Name: Oberea delongi
Common Name: Poplar Twig Borer
Longhorn beetle has a thin body measuring 14 mm long and 2.4 mm broad. The head is black, while the prothorax, the majority of the underside of the body, and the legs are yellow—two smooth, black dorsal bumps on the pronotum and another black mark in front of the scutellum. The pronotum is cylindrical and wider than long, having a convex top surface. Elytra are yellowish-brown in hue with a short black line on the inner edges and a wider black line on the lateral margins.
Yellowish, spherical, and slender; measures 3 to 4 mm long and around 0.5 mm in size.
Mature larvae are pale yellow with a dark brown head and reach 19 to 25 mm in length with a 1.2 mm head capsule width. Larvae are smooth, glossy, legless, and cylindrical, with body segments gradually narrowing toward the rear.
13 mm long with yellowish-white colour.
Populus species, most notably aspen, cottonwoods, and other poplars, are hosts.
This insect may be found across eastern North America, but it is more dangerous in the South, where numerous generations exist.
Life history and Habits:
The life cycle of the poplar borer is long, taking two to three years to complete. Adults are grey beetles with a central yellow stripe on the thorax and some black and yellow stippling lines on the wing covers, measuring approximately 1 and 1/4 inches long. They first appear in late June and can be seen until August. For the first two weeks after emerging from the tree, they feed on their host’s leaves and new shoots. The females then start laying eggs, which they place in holes carved out of the trunk’s bark. Larvae feed on the bark initially, then migrate to the sapwood, where they tunnel upward, creating galleries that are normally approximately a foot long. Larvae are huge, yellowish, round-headed grubs that develop to be about 1 3/8 inch long and can only be found within their tunnels. Unlike other borers, they keep open to the outside during their feeding phase, through which they push the boring dust. Pupation takes place in a chamber cut slightly beneath the bark in late April.