Your Neighbors. Your Arborists.
From Davey Blog Site: ( http://blog.davey.com/2018/08/how-to-get-rid-of-treat-aphid-infestations-in-large-tall-trees/ )
“That sticky film covering your plant’s leaves? It’s called honeydew—but it’s not so sweet.
Honeydew is the waste aphids and several other sap-sucking insects leave behind after snacking on sap. Along with tree leaves, it can drip onto branches, patios, driveways or any areas under the canopy. It can overtake your outdoor space, creating a massive, sticky mess every direction you look!
Plus, a plant stressed by feeding might develop yellow or curled leaves. Though, the leaves or other surfaces may turn black if the honeydew attracts sooty mold fungi.
Though the symptoms sound ugly, aphids actually don’t do much damage to healthy, mature trees. But, if you want to do away with the creepy critters, or save your property from sticky honeydew, here’s what to do.”