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''Phellinus weirii'' is a plant pathogen causing laminated root rot in certain conifers, typically Douglas-fir and western redcedar.〔(【引用サイトリンク】author=Natural Resources Canada ) 〕 It is widespread in the Douglas Fir Growing regions of British Columbia, Washington and Oregon. ==Overview== It is easily recognized when timber is cut because a brown stain will appear on the butt cut. In early stages it will be just a spot in the heart wood, but as the disease advances it will extend most of the way around the heart wood, and in extreme cases may result in a hollow stump. Usually it is not observed more than a few feet above ground level. Losses due to the fungus are estimated at 4.4 million m3 (157 million ft3) of timber in the Northwestern United States and in British Columbia.〔(【引用サイトリンク】 publisher = U.S. Department of Agriculture )〕 Reduced growth rate is an attribute of tree infection.〔http://www.fs.fed.us/pnw/pubs/gtr349/gtr349b.pdf〕 Particular attention is invited to the growth ring patterns visible in the images attached. Image:Laminatedroot1.jpg| Moderately advanced infection Image:Laminatedroot2.jpg| Close up of ''Phellinus weirii'' infection at Apiary, Oregon Image:Rot1.jpg| Hollow log at stump level---An extreme case of infection File:Phellinus weirii on a log.jpg| View of long butt showing reduced rot a few feet up from the stump. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Phellinus weirii」の詳細全文を読む スポンサード リンク
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