What's eating my chinese juniper?

Chinese Juniper is susceptible to juniper scale, which encrusts stems and causes dieback, and to spider mites during hot dry weather. Aphids and bagworms also attack this species. In the US, phomopsis blight (a fungal disease) is a common problem, causing shoot tip dieback especially on young plants after wet springs.

White to grey encrusted scales on stems and foliage; heavily infested branches turn yellow then brown and die; whole plants can decline. Apply horticultural oil in late winter/early spring; use a systemic insecticide (imidacloprid) for established infestations; prune out dead scale-encrusted branches and dispose.

Foliage takes on a dusty, bronzed or stippled look; fine webbing on branch undersides; most severe in summer drought. Spray down foliage with water regularly in hot spells; apply neem oil or insecticidal soap; avoid excess nitrogen fertiliser which promotes soft growth attractive to mites.

Defoliation inside debris-covered silk bags hanging from branches; repeated feeding kills branches and, in heavy years, entire shrubs. Hand-pick bags in winter; spray hatching larvae with Bt (Bacillus thuringiensis) in late spring; spinosad for larger larvae.

Waxy colonies on young stems; wilting shoot tips; sticky honeydew and sooty mould on foliage below colonies. Apply insecticidal soap or neem oil; knock off with water; introduce beneficial insects; control ants that protect aphid colonies.