What's eating my tilia cordata?

Tilia cordata (small-leaved lime) is a favourite host of aphids — particularly the lime aphid — which drench anything beneath the tree with honeydew all summer. Gall mites cause nail galls on leaves, and caterpillars feed on foliage. Aphids are by far the most persistent and frequently noticed problem on limes in UK and European gardens.

Huge colonies on leaf undersides from late spring through summer; continuous honeydew drip coats leaves, cars, and garden furniture below with a sticky layer that develops black sooty mold. No practical chemical control on large limes; tolerate and power-wash surfaces below; encourage natural predators (hoverflies, lacewings, parasitic wasps) which typically crash colonies by August.

Numerous red or green elongated nail-shaped galls erupting from the upper surface of leaves; purely cosmetic — does not harm the tree. No treatment necessary; remove and dispose of heavily galled leaves if appearance matters.

Holes in leaves and rolled or bound leaf tips in spring; defoliation of individual shoots by small green caterpillars. Grease bands on trunk in October to trap wingless female winter moths; Bt spray for caterpillars when first seen.