Barbara Leach – Horticulture Technician
Virginia Cooperative Extension-Roanoke
There’s a new kid on the block, and it is not welcomed. In January, the first Spotted Lanternfly was found in Frederick County, Va. This alien hails from China, where it has been known since the 12th century.
In a balanced eco-system, there are checks. Mishaps occur in nature in cycles; some years good, some years bad. However, all-in-all, things usually work themselves out and we co-exist. Such is not the case when an alien reaches our shores. In our expanding global economy, most countries fight their own battles unwittingly trading new organisms that are not native.
We believe the Spotted lantern Fly likely came in on shipping materials through an Eastern port as much as two years prior to its first confirmed sighting in 2014 in Eastern Pennsylvania. It quickly spread to surrounding counties, over-wintering quite nicely in cold climates. It came here with no natural enemies but found over 70 host plants that it is happy to live on. With such a broad palette, its success in establishing is ensured. With its territory expanding, we are braced for the economic impact to the Virginia industries in grapes, fruit, forests, wood-products and the Green industry.
You can help by learning to identify this insect and being our local eyes. The first nymph stage of this insect is wingless and black with white spots on its body and legs. In later nymph stages, it develops red patches while retaining the white spots. It is quite distinctive looking. The adults are winged and about 1” long by ½” wide. The legs and head are black with a yellow and black striped abdomen. The abdomen may be hidden beneath the wings. At rest, the wings are held in a tent-like fashion and appear greyish or grey-brown with black spots and a finer net-like pattern on the edges. Hind wings, if visible, are red with black spots. There are a few habits that will help distinguish this insect from others. First, they congregate in large numbers. The feed by sucking plant juices and excrete “honeydew” which ferments, turns black and smells like vinegar. This can collect on plants and any adjacent objects. Egg masses, laid on plant bark, contain 30-50 eggs. They may appear shiny if freshly laid and more pellet-like, in 4-7 columns, if older. The total mass may be 1”-1.5” long and ¾” wide. The insect overwinters in the egg stage and hatches in April-May. They spend the front part of the summer going through four nymphal stages before emerging in July, as adults. By August their numbers are great and they breed, lay eggs and start the cycle again by September, continuing through November.
Spotted Lanternfly is best observed at dusk or night as they swarm branches. The adults can fly, but poorly, so you will likely see them jumping and running. Tree-of-Heaven or Paradise tree and grapes are two of their favorite hosts. If you believe you have seen these insects they may be killed by sealing them in a jar with a cotton ball or paper towel soaked in acetone or nail-polish remover and bring them for identification at no charge to your local Virginia Cooperative Extension office. Good quality photographs can be uploaded to https://ask.extension.org/groups/1981/ask. If you have the option to turn on location on your device, it may help in pinpointing them. Avoid moving infested materials from sites. Further questions regarding containing colonies can be directed to Virginia Dept. of Agriculture and Consumer Services. 804/786-3515.
On another note, I have received a lot of calls lately about the “bleaching” of ash trees that have been infested with the Emerald Ash Borer (another alien). Woodpeckers get in there and strip the bark looking for insects, leaving the bleached appearance. There is not much that can be done once trees are infested badly. Evidence leans towards the possibility that Emerald Ash borer was feeding here locally even longer than we knew. If you have ornamental ash, you will need to take steps to protect them from this devastating insect.