What's eating my full moon maple?

Full Moon Maple (Acer shirasawanum 'Aureum') is prone to aphids, scale insects, and caterpillars — the same Acer pest complex. Its thin, golden leaves scorch easily and stressed trees attract more pests. Avoid overhead watering, protect from afternoon sun, and water-blast aphids early before populations build.

Attack new spring growth; sap-sucking distorts and yellows delicate leaves, with honeydew encouraging sooty mould — particularly disfiguring on golden foliage. Water-blast as soon as colonies are seen. Do not use horticultural oil on Acer leaves. Prune back heavily infested tips and bag. Encourage ladybirds and lacewings.

Waxy shells on bark of twigs and branches; heavy infestations reduce vigour and can cause dieback, especially in container-grown specimens. Apply horticultural oil in late winter when dormant. Follow with a crawler-stage spray in late spring. Repot container specimens with fresh compost if root-bound.

Moth larvae chew holes in the large, round leaves; even moderate damage is very visible on this cultivar due to its large leaf surface and golden colour. Hand-pick larvae and egg clusters. Spray with Bt (Bacillus thuringiensis) for larger infestations — targets caterpillars without harming bees or other beneficials.