Cause Cenangium ferruginosum, a fungus reported to be common in Washington on lodgepole pine. The disease is generally restricted to trees that have low vigor as a result of site or climatic conditions. The disease may appear serious and widespread the first year after a severe winter and then subside during the next growing season.
Symptoms The needles on infected twigs become reddish and drop off. Generally limited to the current season's growth, but may occasionally spread into the two-year wood or into older portions of the branch. The dead twigs, devoid of needles, are very conspicuous at the end of the growing season. At this time, the cup-shaped fruiting structures (apothecia) can be found on the dead twigs. They are black to deep brown on the outside and greenish yellow within. In dry weather these fruiting structures are closed and globose, but during wet weather they open and become cup shaped.
Cultural control
- Prune out infected branches.
- Landscape trees-keep trees well-watered and stress free. Also, do not over-fertilize.
Chemical control Unknown if any will work but suspect chemicals applied for other early spring diseases may be effective.
Reference Shaw, C.G., and Harris, M.R. 1960. Important diseases and decays of trees native to Washington. Ag Extension Service, WSU. Extension Bulletin 540.