Spruce broom rust, Chrysomyxa arctostaphyli

Fig. 224  Needles infected showing small spore laden blisters.	Fig. 225  Older orange-yellow broom. Deformity and growth reduction are common.

Distribution:  Throughout the range of spruce in B.C. 

Host Susceptibility:  All native spruce species are susceptible. An alternate host is kinnikinnick. 

Signs & Symptoms: Conspicuous orange-yellow brooms are apparent in the summer months. The discoloured needles are shed in fall and new pale green needles are produced the following spring. Closer examination of broom needles in mid-summer reveal small, orange-yellow blisters filled with spores. Brooms caused by this disease grow perennially and may be greater than 30 years old and up to 2 m in diameter.

Damage: Tree form can be affected by this disease, including the production of spike-tops, dead branches, and stem deformation. This disease may also cause growth reduction and predispose trees to decay fungi and windbreakage. Mortality is sometimes associated with this disease.

Can Be Confused With: The brooming symptoms caused by the spruce broom rust could be confused with those caused by other agents. However, distinguishing features of the rust are the yellow-orange colour of the broom needles in the summer, and the shedding of the needles in the fall.

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Contact Tim Ebata if you have comments on the presentation of this information.

BC Ministry of Forests
Forest Practices Branch
P.O. Box 9513 Stn. Prov. Gov.
Victoria, BC
V8W 9C2

Section phone: (250) 387-8739
Section fax: (250) 387-2136

Last updated March 04, 2002