If you're using Tree of Heaven as a trap tree (like bait) to attract and kill Spotted Lanternfly [SLF], then Penn State has done some research about what to use and when; see their Management Guide and other information in the resource links at the bottom of our SLF page. In Maryland, chemicals in the neonicotinoid class (sometimes called "neonics" for short), which is what is being recommended as systemics in that publication, are not legal for the general public to use and a certified pesticide applicator must be hired to apply them. This will only affect SLF feeding on a treated tree (plus those chemicals take some time to be fully absorbed) and will not prevent more from coming into the yard later. Ideally, if you can afford to do so, the Tree of Heaven should be removed since it's both highly attractive to SLF and itself a very invasive species.

If you cannot budget the removal of the tree and/or do not wish to use pesticides, then hose-off those individuals you can reach on a chilly morning (they should be too sluggish to jump or fly far) and squish those that fall to the ground.

Miri