Dr. Phyto

Japanese maple

Acer palmatum

Diseases & pests on this plant

• olive Verticillium wiltVerticillium dahliae

  Half a tree wilting in summer while the other half stays green, blackish discoloration in cross-section of affected wood, partial recovery in winter then relapse, dieback over 2–4 seasons.

• sunburn / leaf scorchabiotic_sunburn_ornamental

  Bleached papery patches between leaf veins on the side facing the sun, crispy brown leaf margins, no fungal or pest signs, damage appears within hours of strong sun exposure.

• bacterial blight / canker (multi-host)Pseudomonas syringae pv. syringae

  Brown-black angular leaf spots with yellow halos, blackened buds + young shoots that fail to open, sunken brown cankers on stems with bacterial ooze in spring, blossom blight in cool wet bloom periods, branch dieback in heavy infections.

• drought stressabiotic_drought_stress

  Wilting leaves that don't recover by morning, leaf edges browning and curling, drop of older leaves, flowering halts, slow recovery only after deep watering.

• fig branch dieback / Botryosphaeria cankerBotryosphaeria dothidea

  Sudden dieback of individual branches, dark sunken lesions at branch base, internal wood discoloration, gummy exudate.