Why is there sticky sap on my deck, yard, and cars this year?

It is entirely possible that aphids are a concern on your tree. Aphids are a pest of trees that suck plant juices from the tree and foliage. That can be quite damaging to the tree. They secrete a honeydew like substance with a high sugar content that attracts bacteria and creates the black sooty mold under the tree on decks, cars, houses, driveways, etc. It is also possible that the trees may have a soft shelled scale insect that can create a similar sooty mold on the deck. There are many natural predators of aphids including lady bird beetles and their larvae, lacewings, and other beneficial insects. If needed a soil injected treatment can be applied that is translocated throughout the tree to minimize the damaging level of the insect. Foliar spray applications could also be applied to the crown of the tree to reduce aphid populations. Please don't hesiate to contact us with any additional questions, comments, concerns, or to have the trees in question evaluated.