Leaves Twigs Stems and branches	SUMAC - Rhus spp. AFFECTING LEAVES: CONDITION CAUSE Small reddish swellings Eriophyid mite gall AFFECTING TWIGS: CONDITION CAUSE Dark insects on twigs Oystershell scale (Lepidosaphes ulmi) AFFECTING STEMS AND BRANCHES: CONDITION CAUSE Discolored areas, dead bark containing small pinmple-like fruiting bodies (pycnidia) Cytospora canker (Valsa spp., Leucostoma spp.) Wilting and dieback of portions of plant originating from roots Verticillium wilt (Verticillium spp.)
Missoula County Extension Office; Missoula, Montana 59808 - Updated for 2006