We have been in our home for 24 years and for the first time we are getting sap all over our back deck, cars, etc. The deck is turning black. We have a maple tree in the front yard and four oak trees in the backyard. Could it be sap, or something like aphids? How do we treat it?
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. They can be quite damaging to the tree. They secrete a honeydew like substance with a high sugar content that attracts bacteria and creates 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. 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 hesitate to make an appointment with us to have the tree evaluated.
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