Patty from Dallas Tx writes
I have a wasp infestation in a downspout. I cannot see the nest but I do see the flying in and out of the open top which is not accessible from the roof. The opening is about 15 feet from the ground. Can I use Delta Dust for this purpose and if so, how can I get it to the top of the downspout?
Delta Dust Insecticide should not be applied in a downspout. We recommend checking for any debris and clean inside there and ensure they are installed securely. May need to have a professional remove the nest (when they are the least active) and seal crevices around the gutter. The structural voids can be dusted and a residual spray applied monthly to listed exterior areas as well as using wasp traps. Here is a great article on inspecting, treating and preventing wasps.
Answer last updated on: 07/23/2025
