What is the Concern?
Spotted lanternfly (Lycorma delicatula) is an invasive sap-feeding insect from Asia that was first found in the United States in 2014, in Pennsylvania. This non-native pest is known to feed on a wide variety of fruit, ornamentals, and woody trees. Tree-of-heaven, another invasive species, is a favored host to the spotted lanternfly. Other preferred plants include grapes, hops, and the following trees: almond, apple, apricot, cherry, maple, nectarine, oak, peach, pine, plum, poplar, sycamore, walnut, and willow.
The damage caused by spotted lanternfly is from the feeding activity of the adult and nymph stages of the insect. These pests have piercing-sucking mouthparts and damage plants by feeding on the vascular tissue of its host, often resulting in oozing wounds. As a result of feeding, spotted lanternfly can excrete large amounts of a liquid, sugary waste called ‘honeydew’ – a waste product from the insect’s feeding. A buildup of a sticky honeydew may occur on infested plants and any objects below. This can negatively impact outdoor activities during the spring and summer.
Large amounts of honeydew attract other insects and promote the development of sooty mold on the surfaces of leaves and branches, which can give plant material a black fuzzy appearance, and further reduce its resources by blocking sunlight for photosynthesis. A reduction in the ability to carryout photosynthesis weakens a plant and could eventually contribute to its death.
Spotted lanternfly are known to migrate up and down a tree and tend to cluster at the base of the tree during the day or in the tree’s canopy if there is adequate cover. They are easiest to spot at dusk or during the night when they are most active and migrating up and down the trunk of a plant.
The eggs of spotted lanternfly overwinter on the bark of trees and may also occur on any physical object such as firewood, rocks, outdoor furniture, equipment or vehicles parked outside. Since this pest is indiscriminate as to where they lay their eggs, there is a risk of moving this pest by human activities to any new place where infested articles are moved. On average, there are 30-50 eggs in each egg mass.
The greatest risk of accidentally moving this pest is from late September through hard frost, when the egg laying season is the most active. Nymphs emerge from the egg masses in May and will climb up trees to begin feeding in groups. Adults become noticeable in July. Feeding groups of spotted lanternflies are likely to dislodge and drop to the ground or fly if disturbed, and sometimes these numbers can be in the thousands when a pest outbreak occurs.
Adult spotted lanternflies are approximately 1 inch long and one-half inch wide with visually striking wings. Forewings are light brown in color with black spots near the body and a speckled band near the end. Hind wings are scarlet with black spots near the body, have white bands near the center, and have a black net-like pattern at the end. The abdomen of this insect is yellow with black bars. Nymphs in their early stages of development appear black with white spots and turn to a red phase before becoming adults. Egg masses resemble a tan, mud-like material.
If you think you have found spotted lanternfly in Iowa, pleease report it using EDDMapS (Early Detection & Distribution Mapping System). We would be interested in reviewing your submission. Early detection is vital for controlling the spread of this pest.