Rust mites aren’t a problem every year. They tend to be more of a problem during long springs with mild weather. They can be a problem on white pines and hemlocks as well as Fraser fir.

Online Information

CTN 34: Rust Mites in Christmas Trees – fact sheet with photos and information on the life cycle, scouting, and treatment threshold

Focus on Scale Control – including miticide recommendations

HRM – Facts at a Glance – quick facts about hemlock rust mites on Christmas trees (1-page pdf version with photos)

Photo Gallery