Pseudomonas pseudotsugae

Atropellis pinicola

Dermea pseudotsuga

bacterial canker of Douglas fir; occurs on suppressed branches. Tranferred by a midge

Canker of Ponderosa pine; causes large cankers on main bole

Canker of young Douglas fir; causes death of 5-10 year old trees by girdling main bole.

Cytospora abietis (deuteromycete) causes cankers of white and red fir; spores get out of sporocarp via a gelatinous tendril (a cirrhus). Symptoms are flags on white and red fir caused by the mycelium in the canker girdling the base of the branches (two pictures on left); often associated with Arceuthobium abietinum. Pycnidia are small, volcano-shaped sporocarps, found in the canker. (two pictures on right)

Fusarium moniliforme ssp. subglutinans, causative agent of pitch canker of pines. Causes enormous amounts of pitch to accumulate in various places on the trees. At base of tree from roots (top left), cones (second left, top), main bole (3,4 on top and 3 on bottom), and apex of branches (2, bottom). Successive sections through area of pitch (top to bottom, left to right) in top of tree demonstrates amount of pitch. The areas of pitch eventually girdle the branches with evident flags as symptoms. Can cause mortality of trees of all ages.