The Rockdale Gardener

Gardening Posts From Rockdale Cooperative Extension

Silly Psyllids on Beech Trees

The Beech tree in my front has some strange inhabitants. These white insects form colonies on limbs. Below them is a mysterious substance.

The insect is a psyllid or woolly aphids. Psyllids bunch together and move in unison when threatened making themselves look like a larger organism. Psyllids are gregarious insects that suck sap from beech trees. Their sugary excrement accumulates forming yellowish lumps on tree limbs.

The yellowish accumulations under the psyllids is honey dew, a sugary material. Honeydew is excreted in such large amounts that it builds up. The dried material can form into muffin-like formations on limbs and on the ground. Interestingly, this material is believed to be the similar to the “manna from heaven” mentioned in the bible. Eventually, it turns black from mold.

This happens every year in my own yard. The insects and their waste is harmless but sticky when it drips on my car!

Psyllids on a beech

Psyllids bunch together and move in unison when threatened making themselves look a larger organism.

Psyllids

Psyllid insects on a beech tree limb

psyllids on a beech

Psyllids are gregarious insects that suck sap from beech trees. Their sugary excrement builds up forming yellowish lumps on tree limbs. The insects are harmless.