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Our December Conservation Report by Judith Artley.  

The Invasive Insect Spotted Lanternfly

The spotted lanternfly (Lycorma delicatula, (“SLF”) is a stylish insect, with black spots on gray wings and red under-wings, but is an invasive sap-feeding insect from Asia. It was first found in the United States in 2014, in Pennsylvania, and has been found in several other mid-Atlantic states since then. While the main host plant of this pest is the invasive tree-of-heaven (Ailanthus altissima), SLF attacks a variety of trees, shrubs, and vines, including apples, peaches, grapes, maples, oaks, pines and willows. Economists at Penn State estimate a potential annual impact to Pennsylvania's economy of at least $324 million.

   So far, only a couple of dead SLF have been found in Massachusetts. The Mass Department of Agricultural Resources requests us to watch for the SLF and signs of the SLF and report it using the "Report a Pest" form on the Introduced Pests Outreach Project website at FAQ sheets/spottedlanternfly.html.  The website has photos and descriptions to help us in detecting and identifying the SLF.
When the adults fly (which is more of a flutter), the red underwing appears as a flash, giving the insect its name of  Instar nymph stages 1, 2 and 3 are black with white spots. The fourth (final) instar is black, red and white. SLF overwinters as gray egg masses on tree trunks and other smooth surfaces. The egg masses resemble mud. The reporting form has photos, or Google spotted lanternfly for more images.  The SLF feeds by sucking sap from the host plant. The insect excretes honeydew (a sugary substance) which attracts bees, wasps, and other insects. The honeydew builds up and promotesthe growth of sooty mold (fungi), which can cover the plant, forest understories, patio furniture, cars, and anything else found below SLF feeding. The presence of honeydew (sticky surfaces) and sooty mold may be a sign of SLF. A heavy infestation of SLF weakens the host, and sooty mold becomes so thick that it limits photosynthesis further weakening the host.
Inspect your trees and plants for signs of this pest, particularly at dusk and at night when the insects tend to gather in large groups on the trunks or stems of plants. Inspect trees, bricks, stone, and other smooth surfaces for egg masses. Take a photo and report. Scrape egg masses into a plastic zippered bag filled with hand sanitizer, then zip the bag shut and dispose of it properly.
Massachusetts Introduced Pests Outreach Project website
Penn State Extension:
USDA Animal and Plant Health Inspection Service: th ).

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