Goat Moth Caterpillars Erode Tree Trunks from Within

A strong vinegar smell in your garden next to a tree can be a sign of a serious problem. The goat moth caterpillar, up to four inches long and as thick as a finger, has been eating its way through the trunk for years.

The caterpillar's tunnels can be up to three feet long and make the wood unstable, increasing the risk of branches breaking off in the wind or snow.

The infestation usually starts with female goat moths laying up to 700 eggs in cracks on the bark of weak trees. The young caterpillars hatch, eat through the bark as a group, and then each one goes deeper into the wood, making it hard to detect.

Mein schöner Garten notes that gardeners may initially see big round holes in the bark and fine reddish wood shavings at the bottom of the trunk. If left undetected, the infestation can go on for years, eventually leading to the tree's collapse.