Spotted Lanternfly Population Large This Year

Spotted Lanternfly Population Large This Year

Thanks to the mild winter, the spotted lanternfly population in the state is large, say Penn State University Extension educators.


Emelie Swackhamer and Amy Korman offer trapping and control methods for this pest, which was found a few years ago in Pennsylvania.

In many areas in early August, trees were completely covered with feeding nymphs,” they write in their latest small fruit bulletin. “Unsurprisingly, reports of spotted lanternfly from locations previously considered un-infested are significantly on the rise in southeast Pennsylvania.”

Since the presence of spotted lanternfly is a relatively new phenomenon in Pennsylvania, Penn State University is testing pest control options this year.

“Early this month, we began testing contact insecticides including horticultural oil, neem oil, insecticidal soap, and products that contained spinosad, carbaryl, bifenthrin, or pyrethrin as the active ingredient. Additionally, we included two systemic insecticides (both applied as soil drenches and one as a bark spray) in our preliminary trials,” they write.

Korman and Swackhamer say there are certain products that are providing better control options. Of those tested so far, products with the active ingredients bifenthrin, pyrethrin, and carbaryl had an immediate effect on caged lanternfly.

“There was some effect from neem oil and insecticidal soap, but results were variable. Also, the insects were not killed immediately with these products; it took several days to see the full effect. For the systemic products, the bark spray (active ingredient = dinotefuran) appears to outperform the drenches (dinotefuran and imidacloprid),” they write.

Korman and Swackhamer say drenches might have performed better with an application earlier in the season. They noted adult spotted lanternflies started emerging in early August this year. While researchers believe the insect must feed on Tree of Heaven to complete its life cycle, they are continuing to monitor other host plants the insect may feed on.