Spotted lanternfly (SLF) populations are very active in multiple NJ counties such as Hunterdon, where large numbers of adults can be seen feeding. As of last week, the majority of adults were observed feeding on tree of heaven. Where possible, tree of heaven should be treated with either an herbicide and/or an insecticide. PSU has information on treatment here https://extension.psu.edu/tree-of-heaven

Based on observations in Pennsylvania, feeding by adult Spotted Lanternfly in grapes can reduce overwintering survival and may have broader impacts to vine health. Spotted lanternfly is a phloem feeding insect that feeds directly on the cordon, not on the fruit. As they feed, they expel the extra sugars from their bodies in the form of honeydew. Honeydew can buildup underneath trees or on plant material beneath vines and can be colonized by sooty mold fungi. In grapes, sooty mold can develop on clusters, significantly reducing quality, although this has not yet been observed in the USA. More importantly in areas with high SLF populations, vine health has deteriorated quickly. In Pennsylvania both a decrease in winter hardiness and vine death has occurred.

Vines should be watched closely to determine if SLF adults are dispersing into the vineyards and feeding. Populations will likely be higher along vineyard edges. If feeding occurs, an insecticide treatment may be warranted. The adults have not started to lay eggs yet so this is a critical time for population management. Multiple insecticide materials are effective against the adult stages. Recommendations from PennState in grapes are:

Always follow the insecticide label for use and application instructions. Please note that there is variation in the residual activity of each material and some materials require a 2(ee) label for use in grapes. BotaniGard is also being evaluated as a biological insecticide by PSU.

New sightings of spotted lanternfly in NJ can be reported, along with a picture and address to slanternfly@njaes.rutgers.edu