Question
We have a nursery and we have aphids and mold covering our fruit trees, oak, maple trees, crape myrtles well basically if it has a leaf it's infested. We have used triple action and currently using sevin

Answer
Joey:
As mentioned earlier, aphids are one of those insects that produces "honeydew"- the sugary excrement on which sooty mold grows.  From a reference I obtained, sevin is not very effective for aphids.  Such insecticides that contain an active ingredient such as imidacloprid, acephate, or bifenthrin are labeled for aphids.

Regards
Steve