The spotted laternfly (SLF) has been seen throughout New Jersey and many of our customers have seen them on job sites. We are often asked about the impact on ornamental plants. Here is what we know.
SLF is a serious invasive pest with a healthy appetite for plants and it can be a significant nuisance, affecting the quality of life and enjoyment of the outdoors.
Healthy and established ornamental trees have not been recorded to have died from spotted lanternfly, though canopy dieback and plant health decline has been observed, particularly on some of spotted lanternflies favorite hosts including black walnut and maple.
We are not aware of SLF attacking ornamental shrubs, or perennials, Ground covers under trees infested with SLFs may be affected. As SLF feeds, the insect excretes honeydew (a sugary substance) which can attract bees, wasps, and other insects. The honeydew also builds up and promotes the growth for sooty mold (fungi), which can cover the plant, forest understories, patio furniture, cars, and anything else found below SLF feeding.
If you see a spotted laternfly - kill it. They move quickly so be ready. There are multiple ways to try and reduce the populations as noted below.
WHAT TO LOOK FOR
- Egg masses vary in size.
- The masses are typically an inch long by 3/4 of an inch wide.
- The female secretes a white, waxy substance over the eggs to protect the mass.
- When dried, the egg masses look like light grayish splotches of mud, cement, or lichen.
- Each mass holds 30 to 50 eggs.
Option 1: Scraping
- Fill a plastic baggie with a few ounces of rubbing alcohol or hand sanitizer.
- Scrape the eggs off the surface with a credit card, putty knife, or butter knife into the bag.
- Make sure the eggs come in contact with the alcohol/sanitizer. The eggs must remain in the alcohol solution.
- Take the bag, place it in another bag, and discard it.
Option 2: Crushing
- Crush the eggs by dragging a credit card, putty knife, or another hard implement across the egg mass.
- The eggs will pop as you press down. You may see liquid released as the eggs underneath burst.
Option 3: Insecticides
- There are insecticide options for reducing the population. Scroll to the "Chemical Control" section of this page for the various insecticides that are proven to work. Please be aware some of these insecticides are harmful to animals and pollinators.
We will continue to stay in close contact with our state agriculture department and when we learn more we will publish it on this page.
An excellent guide for landscape professionals from Penn State (https://extension.psu.edu/spotted-lanternfly-management-for-landscape-professionals)
NJ Department Of Agriculture Page - an excellent page with a lot of detail. Note the tabs on the top of the page for the different sections (https://www.nj.gov/agriculture/divisions/pi/prog/pests-diseases/spotted-lanternfly/)
An in depth guide from Penn State (https://extension.psu.edu/spotted-lanternfly-management-resources)
US Department Of Agriculture - a comprehensive resource from the USDA. (https://www.aphis.usda.gov/aphis/ourfocus/planthealth/plant-pest-and-disease-programs/pests-and-diseases/sa_insects/slf)
Plants That Are Susceptible To The Spotted Laternfly