Asian Longhorned Beetle – A New Invasive Tree Pest In South Carolina

The Asian longhorned beetle (ALB; Anoplophora glabripennis) is not easy to miss – adults of this large, black beetle with white spots, black and white striped antennae, and blueish feet are between 1 and 1 ½” long (Fig. 1). ALB larvae are equally striking as the large, white segmented larvae can be nearly 2” in length (Fig. 2). Established populations in the U.S. are found in Massachusetts, New York, and Ohio, and a new infestation was recently found in Charleston County, South Carolina.

ALB uses several different tree species as hosts (Table 1), many of which grow in South Carolina. Host trees can be found in natural or managed landscapes, such as lawns, medians, or public areas.

Table 1. Known host trees for ALB.

Adults emerge in late spring or summer, creating large round exit holes as they chew their way out of the tree (Fig. 3). Adults then mate and feed on the bark of small twigs, though this feeding damage is negligible in comparison to that done by the larvae. Adult females then chew an “oviposition pit” into the bark and deposit an egg (Fig. 4). The egg hatches and the larva chews its way into the tree. As the larva grows, it makes larger and larger tunnels (Fig. 5), and these tunnels eventually kill the tree and make it highly susceptible to breaking. For this reason, larvae are the most damaging life stage of ALB. In many cases, feeding by larvae results in sawdust or shavings being deposited on the tree trunk, branches, or base of the tree (Fig. 6).

The cottonwood borer (Plectrodera scalator) is a native longhorned beetle that looks similar to the ALB (Fig. 7). This beetle is not damaging and can be found in natural habitats across the state.

More information on the ALB can be found on the Asian longhorned beetle