Box Tree Moth
Risk near you, next 48h
See whether your local forecast favours this disease right now.
When it strikes
Remove affected material now
Take out the affected leaves, shoots or whole plants before the next wet spell, bag them as you cut, and wash your hands and tools before touching healthy plants.
Carried by insects
An insect moves it plant to plant, so controlling the carrier matters as much as treating the symptom. Check for the vector before assuming the plants infected each other directly.
Safe to compost
No pathogen carries over on this material, so it can go on an ordinary heap with the rest of the garden waste.
When and where to look
Scout the planting while temperatures hold between 12°C and 32°C.
The signs that lead here
About
Box tree moth (Cydalima perspectalis) arrived in Europe from East Asia in 2007 and has spread across the continent since. Its caterpillars can strip a mature box hedge to bare twigs in under two weeks, and there are two or three generations a year.
Symptoms
Fine white webbing spun between leaves and twigs, with green caterpillars marked with black stripes and white dots feeding inside it. Leaves are eaten to a skeleton, then the bark is stripped, which kills the shoot outright.
Organic Treatment
Spray Bacillus thuringiensis onto small caterpillars and repeat every 7–10 days through each generation — it only works on young larvae, so timing decides everything. Clip out webbed sections and destroy them, and pick caterpillars off by hand on smaller plants.
Chemical Treatment
Deltamethrin or acetamiprid penetrates the webbing better than Bt but kills pollinators, so spray at dusk and never on flowering plants nearby. Repeat treatment is unavoidable given the multiple generations.
Prevention
Hang a pheromone trap from April to time your sprays to the flights rather than guessing. Inspect hedges weekly through the season, and consider replanting badly damaged hedges with Ilex crenata, Japanese holly or yew.
Related problems
Box Tree Moth risk by location
Each location has a month-by-month profile computed from the weather archive: how many hours a year actually meet this disease’s thresholds.