What's eating my betula pendula?

Silver birch is most endangered by the bronze birch borer, which causes top-down branch death particularly in dry or hot sites. Leaf miners produce cosmetic blotching from midsummer and aphid colonies form under the canopy. Aphids and miners rarely kill a vigorous tree but weaken it and make it more borer-susceptible.

D-shaped exit holes in bark; winding larval galleries visible under stripped bark; progressive crown dieback starting at the top Plant in cooler, moister sites; water deeply in drought; remove infested branches early; systemic imidacloprid soil drench as preventative on valued specimens

Tan blotch mines on leaves from late spring; leaves brown and drop prematurely; repeated defoliation stresses the tree Collect and destroy fallen leaves; apply systemic insecticide soil drench in early spring for persistent infestations; avoid overhead watering that spreads spores

Large yellow-green colonies on new growth; sticky honeydew and sooty mould below; minor leaf distortion Blast off with water; insecticidal soap or neem; natural predators (ladybirds, lacewings) usually suppress colonies within a few weeks

Notched or skeletonised leaves in late spring; silken webbing on shoots; heavy attacks can defoliate entire branches Apply sticky grease bands around the trunk in October to trap wingless female winter moths; Bt spray for caterpillars on accessible branches; hand-pick buff-tip colonies