Friday, December 18, 2015

Pest Alert: Spotted lanternfly


Be on the lookout for a new exotic insect, the spotted lanternfly (Lycorma delicatula)! Native to Southeast Asia, the spotted lanternfly moved to the Korean peninsula in 2006 where it has become a pests of fruit crops, including grapes, apples and pears, and forest trees. In 2014 a population was discovered in Pennsylvania, but there is evidence that it had been there at least two years prior.

An adult specimen of the spotted lanternfly with its wings spread. Adults are about 1 inch long. Photo credit Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org.

An adult and nymph spotted lanternfly on a tree trunk. Photo credit Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org.

Late-stage nymph of the spotted lanternfly. Photo credit Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org.

Early-stage nymph of the spotted lanternfly. Photo credit Lawrence Barringer, Pennsylvania Department of Agriculture, Bugwood.org.
The spotted lanternfly is a phloem-sucking planthopper. Although it has wings as an adult and can fly it tends to be more of a hopper. Females lay their egg masses on a variety of smooth surfaces, including tree bark, dead wood, outdoor furniture, and vehicles. Currently limited to Pennsylvania, unwitting transport of eggmasses could rapidly expand the range of this insect.

The adults prefer to feed on tree-of-heaven, Ailanthus altissima, which will be good news to native plant lovers, but it also feeds on grape vines and poses a grave threat to grape growers. The nymphs feed on a much wider variety of hosts, including a number of stone and pome fruits, and forest trees including pines, maples, and oaks.

The adults and the nymphs tend to feed nocturnally in groups, so it is best to look for them at dusk or at night. Feeding often results in weeping wounds on the tree bark and the build-up of honeydew and sooty mold at the base of the tree.

The adults and nymphs are striking, which often indicates that an animal is unpalatable. It appears they sequester toxins from the tree-of-heaven that protect them from vertebrate predators, such as birds.

It is too early to say what impact this insect could have on South Carolina’s forests and agriculture if it arrived, but it is better to be prepared. In its native habitat natural enemies and diseases keep populations of the spotted lanternfly below damaging thresholds. In Korea and North America there are no natural enemies and so populations get larger than they normally would.
If you suspect that you have found spotted lanternfly please contact your local extension agent or the South Carolina Forestry Commission at (803) 896-8838 or djenkins@scfc.gov