Spotted Lanternfly (SLF) II - Scouting and Management
The Spotted Lanternfly (SLF) is now confirmed in Cecil and Harford Counties in Maryland, and has the potential to be a very significant pest in vineyards. For background information, please see the TimelyVit Spotted Lanternfly (SLF) I—Background, for basic information. This Timely Viticulture was created to give growers information on how to scout for the pest and some management options and strategies. This is a “newly introduced” which has already cause significant damage to Pennsylvania vineyards.
- Overwintering egg masses are commonly found on grapevine trunks and Tree of Heaven (TOH) but also on objects such as rock, vehicles, etc.
- Old egg masses appear as rows of 30-50 brownish seed-like deposits in 4-7 columns on the trunk, in a mass that is roughly an inch long (figure right).
- When egg masses are located, destroy by scraping into a container with 70% alcohol and removing from the vineyard.
- The emerging nymphs move from the surrounding woods and TOH to grape and other hosts. Young immature stages (1-3 instars) resemble a large black aphid with white spots (figure B); the final most mature immature stage (4th instar) develops bright red patches and are over 1/2” long (figure C).
Nymphs and adults are vascular feeders (phloem and xylem) so they will primarily be found on trunks, cordons and canes; they are NOT typically found on the foliage; all 4 immature stages of SLF can feed on grape wood.
- In mid-to-late summer and early in the fall the adults will heavily congregate on stems of Tree of Heaven and grapevines (figure G).
- The adult SLF is approximately 1" long and 1/2" wide. The forewing is grey with black spots and gray tips; the hind wings have patches of red and black separated by a white band (figure E). The abdomen is yellow with broad black bands (figure E).
- Sooty mold patches on clusters and leaves can be a sign of feeding.
- In late fall, search and destroy efforts should switch to location of egg masses. Adults lay egg masses on trees and nearby smooth surfaces, like stone, outdoor furniture, vehicles, and other structures.
- Newly laid egg masses have a grey pitch like covering over the eggs (figure A).
- Small populations can be crushed or swatted by hand.
- Insecticides will kill adults and nymphs, but since this pest is new, there are no products labelled
specifically for use against spotted lanternflies.*
- Penn State Extension is testing insecticides to determine which are most effective at controlling SLF; many insecticides are effective in killing this pest.
- There are no formal insecticide recommendations at this time however insecticides with the active ingredients acetamiprid (Assail), bifenthrin (Brigade), dinotefuran (Venom/Scorpion), imidacloprid (Admire Pro), carbaryl (Sevin), malathion (Malathion), pyrethrin (Pyganic), and thiamethoxam (Actara), can provide effective control. (Not all products have been tested against the Spotted Lanternfly specifically, and additional research is ongoing to determine efficacy.) Always follow the label and rotate chemical classes appropriately.
- Neem oil and insecticidal soap can provide some control, but soaps do not appear to control adults.
- Application of insecticides may kill SLF within the vineyard, but be aware that reinfestation of SLF from the surrounding woodlot is possible.
- Since it is such a new pest in the states, not much is known about its natural enemies.
Population Management Utilizing Tree Wraps/Banding
- The immature SLF does not fly, so they must walk up to their host (vines/tree).
- There has been some success (with trees) trapping the SLF on sticky bands placed around the circumference of the tree. Insects walk onto the band and are trapped.
- This can be effective in trapping and reducing the population, although we are not sure if it will work with grapevines with irregular flakey bark.