Swollen galls on an apple root caused by feeding woolly apple aphids, Eriosoma lanigerum. White wax excreted by the aphids is visible on some of the galls.
Swollen galls on an apple root caused by feeding woolly apple aphids, Eriosoma lanigerum. White wax excreted by the aphids is visible on some of the galls. Credit: Jack Kelly Clark
