Something black on a beech tree limb

By Aaron Horrell

Last Sunday while walking in the woods I noticed a black object about six feet up the trunk of an American beech tree. At first I thought it was a black squirrel or bird. But it did not move as I cautiously approached.

The black something turned out to be a soft mold called "spongy sooty beech mold." This mold grows during summer when tiny fuzzy white aphids called "woolly beech aphids" feasting on live beech tree leaves produce a by-product called honeydew. When this honeydew drips on beech tree limbs below, spongy sooty beech mold will grow from it.

During summer this black mold, which often grows high in the tree, is not easily noticed. Winter is the best time to look for it. First though, you will need to find a forest with several beech trees.