We are still learning about Spotted Lanternfly, an invasive insect attacking trees and causing property damage across Pennsylvania. Penn State, along with the PA Department of Agriculture and the USDA, have been researching the habits and life cycle of Spotted Lanternfly since it first appeared in Berks County in 2014. There’s still so much unknown about these bugs. However, we do know for certain that the Tree of Heaven (Ailanthus) is a magnet for these pests. If you have an Ailanthus tree on your property, removal may be the best way to avoid an invasion of Spotted Lanternfly.
Why Is Spotted Lanternfly Spreading So Fast?
Spotted Lanternfly came from Asia, where natural predators keep the species from multiplying too quickly. Unfortunately, here in the United States, it’s spreading rapidly because those known predators aren’t around to keep it in check.
Although this insect’s population is growing exponentially each year, there are many things you can do to control it:
- Use sticky bands on your trees starting in early May to catch any young nymphs
- Treat any infested trees with a basal trunk spray in July to kill adults as they crawl up the tree
- Treat any infested trees with 1-2 foliar sprays in late August – early November to kill adults in the crown of the tree
- Scrape and destroy all egg masses on any reachable branches and the trunk of the tree. Also check for egg masses on the undersides of every surface outside, including playsets, grills, decking, railings, patio furniture and siding.
- Remove all Ailanthus trees and Ailanthus tree sprouts from your property.
What is an Ailanthus Tree?
The main host tree for Spotted Lanternfly is the Ailanthus Altissima, or Tree of Heaven. Ironically, Ailanthus trees came to the U.S. from China around the 1780’s. Classified as “weed trees”, they reproduce by both seed and root sprouts. If you have an Ailanthus tree on your property, you may see mall sprout trees pop up from time to time all around your yard. In fact, shoots can sprout from the tree’s roots from as far away as 5o feet around the tree!
Ailanthus trees can grow up to 100 feet tall and the trunk can be nearly 6 feet in diameter. They have a great canopy and often thrive easily in conditions other trees don’t. In fact, you may view your Ailanthus tree as an important part of your yard that you don’t want to remove. That’s understandable! However, if you have any other valuable trees on your property, your Ailanthus will attract Spotted Lanternfly and they could also swarm your other trees.
At this point, it’s hard to determine the long-term damage to trees. Emeilie Swackhamer, Penn State Horticulture Director, has been following the Spotted Lanternfly and monitoring infested trees for 4 years. She explains in an informational YouTube video that while it’s still too early to say what the long-term effects will be, the insects are definitely causing significant die-back and defoliating branches in trees.
Thanks to the research done by Penn State, we know that Spotted Lanternfly also swarm other types of trees, including Black Walnuts, Maples, Birches, Willows, and many more. According to the PA Department of Agriculture, they attack more than 70 species of trees, and 25 of them are found in Pennsylvania. Keeping your Ailanthus tree is like inviting Spotted Lanternfly to a buffet in the backyard!
How to Remove Ailanthus Trees
If you have an Ailanthus tree or are not sure, you should call Giroud at 215-682-7704 and schedule a FREE inspection. In most cases, Giroud recommends removing Ailanthus trees and grinding the stumps down as deeply as possible.
After removing the Ailanthus tree and stump, sprouts may still pop up on your property. The good news is they are easy to remove! Grab the shoot by its base and pull upward gently to remove the young tree and all of its roots.
Check out this instructional video with Giroud Arborist, Mike Chenail, to see how easy it is to remove these small shoots and where they are typically found!