Why Are My Cherry Tree Leaves Eaten by Caterpillars?

Ragged, chewed cherry leaves with irregular holes or entire leaf areas consumed are the work of caterpillars — the larval stage of moths that use cherry and other members of the Prunus family as food plants. A moderate level of caterpillar feeding is a normal part of garden ecology and rarely harms a healthy cherry tree. Heavy infestations, particularly early in the season when the canopy is developing, are worth addressing to prevent the tree being weakened at a critical time.

Winter moth caterpillars

The winter moth (Operophtera brumata) is one of the most common causes of early leaf damage on cherry trees. The female moths are wingless and crawl up the trunk in autumn and winter to lay eggs near the buds. The tiny green looper caterpillars hatch in spring as the buds open and immediately begin feeding on the young leaves and flowers. Damage appears as small, irregular holes in very young leaves from late March onwards, often with silk threads binding leaves together. Fitting a grease band or physical barrier around the trunk in October prevents wingless females from ascending to lay eggs, breaking the cycle without any chemical treatment.

Tortrix moth caterpillars

Several tortrix moth species use cherry as a food plant. Their caterpillars are typically pale green or yellow-green, and they spin silk threads that bind leaves together into a loose shelter within which they feed. You will see rolled or bound leaf clusters with frass (dark droppings) visible inside. The binding makes contact sprays less effective once shelters are established. Picking off and destroying bound leaf clusters is effective at low infestation levels. Biological control with Bacillus thuringiensis (Bt) spray, a naturally occurring bacterium that kills caterpillars on contact, is safe for all other insects and effective when applied early in the caterpillar's development.

Cherry ermine moth

In some seasons cherry ermine moth caterpillars can completely defoliate branches, covering them in silk webbing within which hundreds of small caterpillars feed communally. This looks dramatic but established trees usually recover fully, producing a second flush of leaves. Prune out and destroy affected branches when colonies are young and contained to prevent spread.

Encouraging natural predators

Blue tits, great tits and other small birds are highly effective predators of caterpillars on fruit trees, and a single nest box near the orchard can dramatically reduce caterpillar populations across a season. Avoiding any broad-spectrum insecticide use protects the parasitic wasps and ground beetles that prey on caterpillar pupae in the soil.