DEM Announces it will Spray Targeted Sections of Smithfield Along Douglas Pike that have Spotted Lanternfly Infestations with Insecticide Treatments

Published on Monday, September 19, 2022

PROVIDENCE, RI: The Rhode Island Department of Environmental Management (DEM) is announcing that it will begin treating pockets of spotted lanternfly (SLF) infestation that have been found along Douglas Pike (Route 7) in Smithfield with insecticide, weather permitting, on Wednesday, September 21. Applicators using backpack sprayers with wands will “contact spray” Bifenthrin, a United States Environmental Protection Agency-approved pesticide, directly on trees and bushes with substantial numbers of adult lanternflies.

This kind of treatment kills the invasive pests on contact and has been used effectively in Pennsylvania and other Mid-Atlantic states that have been threatened by SLF, which feeds on plant sap using a piercing mouthpart and targets an extremely broad range of agricultural crops and tree species. DEM announced Aug. 22 that it had found the state’s first SLF population along the Douglas Pike corridor and surrounding neighborhoods. The United States Department of Agriculture (USDA) Animal and Plant Health Inspection Service (APHIS) confirmed the detection. DEM scientists have spent the last three weeks surveying the area to gauge infestation levels.

DEM is emphasizing that the planned pesticide treatment is not a large-scale operation. The project crew will likely consist of two contracted pesticide applicators working for two to three weeks focusing on several of the most infested points within the map shown on the previous page. DEM Division of Agriculture and Forest Environment staff will notify business and property owners before the spraying takes place. Because this insect is a hitchhiker and SLF adults don’t survive the winter, DEM has a narrow treatment window and is prioritizing treatment by focusing resources on affected areas along high-volume transportation routes where there is a greater chance that SLF adults will jump onto a car or truck and relocate. DEM also stresses that this is an initial treatment in a finite area. Based on the experience of other states with established SLF populations, SLF will probably spread to other areas in Rhode Island. Depending on the spread and severity of the damage caused, much larger pesticidal control treatments may be needed in the future.

“Rhode Island must move aggressively in the small area where the spotted lanternfly has been found to control the occurrence before its spreads widely and causes considerable economic harm, as it has done in Pennsylvania, New Jersey, and other states,” said DEM Director Terry Gray. “Serious SLF infestations around the state could jeopardize thousands of acres of orchards, berry crops, vineyards, and nursery stock that are the source of people’s livelihoods and contribute to our food supply. We are using a federally registered pesticide that the EPA has deemed safe when used in accordance with label directions. Our state-licensed and insured applicators are trained to apply such products effectively while protecting the environment and non-target species.”

Despite its name, SLF is not a fly but a leafhopper. SLF adults tend to fly to new trees to feed in the late summer. The adult female insect lays eggs in the fall. The adults don’t survive the winter, but the egg masses do. Typically about an inch long and resembling a smear of mud, the egg masses can contain up to 50 eggs and are laid on trees, rocks, and anything left outdoors, such as pallets, boats, trailers, lawn furniture, RVs, and firewood. Although APHIS and institutions, including the PennState Extension, are currently working to develop biological practices for SLF management, “the most effective control measure to date is the use of insecticides,” PennState Extension says in a lanternfly guidance document. Currently, there are no known natural enemies of SLF that are expected to reduce populations in the Unites States. Some generalist predators such as spiders, praying mantises, parasitoids, and birds will attack and eat SLF, but cannot be considered an effective large-scale biological control.

Bifenthrin is EPA-approved and safe to people. DEM applicators will follow all product label requirements and avoid spraying flowering plants to protect pollinators. Also, because the product is known to be toxic to fish, no spray will be applied near water. SLF was first detected in Pennsylvania in 2014 and has established populations in 14 states counting Rhode Island. It is a threat to many fruit crops such as apples, apricots, cherries, grapes, hops, nectarines, peaches, and plums as well as maple, oak, pine, poplar, sycamore, walnut, and willow trees. SLF does not fly long distances, but it is an able hitchhiker. DEM advises that if members of the public find a single SLF or an SLF population, to Spot, Squash, and Send in sightings to www.dem.ri.gov/reportspottedlanternfly. To learn more about SLF, visit DEM’s Agricultural Pest Alerts website or the URI website.