What's eating my acer rubrum 'autumn blaze'?

Acer rubrum 'Autumn Blaze' (a red × silver maple hybrid) is susceptible to the same pests as red maple. Cottony maple scale is the most prevalent problem. Verticillium wilt aside, insects include aphids, gall mites, and the invasive Asian longhorned beetle. Deer will browse young trees before the trunk hardens.

Fluffy white egg masses clustered on twigs and branches in early summer; honeydew, sooty mould, leaf yellowing, and dieback with heavy infestations Target crawlers with horticultural oil in early summer; apply dormant oil in spring; preserve parasitic wasps by avoiding pyrethroids

Red or green raised pustule galls on upper leaf surfaces; purely cosmetic and does not threaten tree health Rake fallen leaves to reduce overwintering mites; a dormant miticide or horticultural oil spray can prevent build-up; no action needed on otherwise healthy trees

Colonies on shoot tips in spring; distorted new leaves; honeydew attracting ants and promoting sooty mould Knock off with water; introduce or attract beneficial insects; insecticidal soap spray for persistent colonies

Bark stripping and antler rubbing on young trunks in autumn; browsing of low branches in winter and early spring Fit spiral tree guards or wire-mesh cylinders on young trunks for the first 3–5 years; deer repellent sprays on accessible branches; install fencing in high-pressure areas