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Forest Root Rot Video Available

PULLMAN, Wash. — “The Rotten Truth,” a new video offered by Washington State University Cooperative Extension, shows forest managers how to diagnose, manage and prevent the three most common root rots in Northwest forests: Laminated root rot, Armillaria root rot and Annosus Root and Butt rot.

Laminated root rot, the most serious of the three, most often strikes Douglas fir and Grand fir. One of the most identifiable characteristics of Laminated root rot is the decay in roots and stumps of downed trees. The wood of the root will break apart easily between the annual rings and will be heavily pitted on both sides. An infected stand will be riddled with downed trees lying in different directions.

Conifers are the favorite food of Armillaria root rot, although it will also attack hardwoods and shrubs. Above ground symptoms include a white fungal growth between the bark and the wood at the base of infected trees.

Two different strains of the fungus that causes Annosus Root and Butt rot are found in the Northwest. One attacks pines; the other Douglas and Grand fir and hemlock. Decayed wood contains white mycelium and small black flecks about the size of rice grains.

The 36-minute tape is a joint production of the Washington State Department of Natural Resources, the College of Forest Resources at the University of Washington, the U.S. Department of Agriculture Forest Service R-6 Cooperative Programs and Washington State University Cooperative Extension.

Copies of VT 0094 “The Rotten Truth” can be ordered from the Washington State University Cooperative Extension Bulletins Office by calling 1-800-723-1763. Cost is $24 plus shipping and handling. Washington residents should add 7.5 percent state sales tax The video is available in NTSC VHS, PAL and SECAM formats available for an additional charge.

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