Spotted Lanternflies don't need treatment in home landscapes, as they do not pose a serious threat to garden plants. No insecticide is specific to Spotted Lanternfly (SLF) where it will not pose some risk of harm to pollinators, beneficial insects, or other wildlife that come into contact with its residues so for this reason we generally don't recommend to use any insecticide. 

If they are leaving the sticky honeydew residue on the deck, you can use a pressure washer or strong stream of hose water to spray it off.  

You can also build a do it yourself trap to collect them so you don't have as many colonizing in one place.

Let us know if you have further questions. 

Emily

You're welcome!