Aphids are an all-too-common pest in gardens and landscapes. Also known as greenflies and blackflies, they feast on sap.

Because of their small size, however, aphids often go unnoticed. When fully grown, aphids are only about one-eighth of an inch long.

While you can’t easily spot them from afar, there are other ways to tell if large trees are infected with aphids.

Sticky Leaves

If you believe aphids have infested a large tree in your landscape, look at the leaves to see if they are sticky.

As previously mentioned, these otherwise small pests feast on sap. They’ll suck the sap the sap out of leaves while leaving behind a sticky residue in their wake.

Black Fungi

Another possible sign of an aphid infestation in large trees is the presence of black fungi.

As the sap sits on the tree’s leaves, it encourages the growth of black fungi. Fungal spores in the air will fall on the sap, at which point the fungi will begin to spread.

Sap Below the Tree

You should check around the base of the tree – particularly the area of the ground directly below the canopy – to see if there’s sap present.

When aphids feast on a tree’s sap, some of the sap will inevitably fall to the ground below. Therefore, the presence of sap below a tree may suggest that it’s infested with aphids.

Yellow Spots

The presence of yellow spots on a tree’s leaves may also indicate an aphid infestation.

Most aphids are yellow, so when they infest a tree, they look like yellow spots. When viewed up closed, you may even notice them moving. Regardless, if you see groups of yellow spots on a tree’s leaves, there’s a good chance that it’s suffering from an aphid infestation.

Curled Leaves

Perhaps one of the most common signs of an aphid infestation in large trees is curled leaves.

As aphids feast on a tree’s sap, they’ll chew through its leaves. Over time, this may cause the leaves to curl upward or downward.

Galls

Finally, you should inspect large trees in your landscape to see if they contain galls.

Like many other garden pests, aphids lay eggs to reproduce. When aphids lay eggs inside or on a tree, the tree may respond by producing large growths known as galls. The galls themselves are typically harmless, but they are indicative of an infestation.

The Woodsman Company offers tree planting, tree pruning and shrub trimming, tree removal and stump grinding as well as a tree wellness program.

If we can help with any of your tree care needs give us a call at 512-846-2535 or 512-940-0799 or