The spotted lanternfly (Lycorma delicatula) was detected in Pennsylvania in September 2014, and in Delaware and New York in 2017. It attacks a number of economically important tree species including fruit trees, grapevine, and conifers. It is introduced in South Korea, where it spread rapidly and became a serious pest of grape, causing substantial economic impact. If it were able to establish here in Canada it could pose a threat to viticulture and fruit growing industries.
The spotted lanternfly is a large plant hopper. The adult female lanternfly lays her eggs in the fall, in masses of 30-50, and covers the mass with a putty-like covering (see photo in sidebar). They prefer tree of heaven for egg laying, but other flat vertical surfaces including other plants, and manufactured objects such as vehicles and yard furniture are also used, especially those near to tree of heaven. Eggs hatch in the late spring and early summer (mid-May in Pennsylvania). Emerging offspring, called nymphs, go through four developmental stages (instars) before becoming adults in mid-summer (late July in Pennsylvania). Nymphs feed on a range of tree species, but adults prefer to feed on tree of heaven and grapevine. The adults and nymphs feed on sap in the tree's stems and leaves using their piercing-sucking mouthparts. Lanternflies (adults and nymphs) climb trees and other plants jumping to another place when they encounter an obstacle; when they are knocked down they climb another plant or object (falling-ascending behaviour). The insect overwinters in the egg stage which is sensitive to colder temperatures. There is one generation per year.
Trees at risk
The spotted lanternfly's preferred host is tree of heaven, which is also native to China and is planted (and often invasive) in North America. The lanternfly also attacks grapevine, apple, stone fruit and pine, and may attack other tree species when populations are high. Lanternfly damages the tree through its feeding activity - the loss of sap weakens the plant and can kill it when there are large number of lanternflies feeding on one tree. Mould growth on sugary exudates (see below) can impair photosynthesis, reducing quality and yield of fruit crops.
The spotted lanternfly is native to China, is also found in Japan and Vietnam, and is introduced in South Korea. In North America it is only known to be present in certain counties in Pennsylvania.
Spotted lanternflies are very distinctive looking, and are not likely to be confused with any other insect here in Canada. In the spring or early summer look for nymphs feeding on smaller plants, vines and new growth of trees and shrubs. Young nymphs are black with white spots and typically feed in groups (see photo in sidebar). Later in the year older nymphs, which develop a red back and wing pads, along with adults, may be seen feeding, most often on the branches and trunk of tree of heaven or on grapevine. Adults, about 2-2.5 cm long, have a black head and grayish-brown wings with black spots toward the base of the wing and a black band at the outer wing (photo in sidebar). The distinctive hind wing (scarlet red band with black spots at the base, followed by a white and then a black band toward the outer wing) and abdomen (yellow with black bands) can be seen when the adult is startled, or flying. During the day, adults are more likely to be found at the base of the plant stem.
Egg masses may be found on smooth surfaces of the trunk of tree of heaven, or on vertical surfaces of other plants or objects near to tree of heaven. New eggs masses have a grey waxy or putty-like cover, but old, hatched, egg masses look like brownish seeds arranged in columns (see photos in sidebar). The egg mass is approximately 2 cm long.
Attacked trees may have wounds oozing sap. Sap, along with honeydew secreted by the lanternflies, may accumulate at the base of the tree, where there may be mold growing on it. Activity of other insects such as ants, bees or wasps may be seen as they feed on the sap and honeydew. Leaves of attacked branches may wilt and die.
Read more about spotted lanternfly detection
What you can do
If you have tree of heaven in your yard, check it, and objects near it, for egg masses or for feeding insects.
If you think you have found spotted lanternfly in Canada, contact the CFIA Plant Health Surveillance Unit.
Read more about spotted lanternfly biology, damage and risk.
Read an overview of spotted lanternfly from a North American perspective.