I spend a fair bit of time on forested slopes assessing slope stability. This particular site has some fungus trouble. The Douglas firs over an area of the site have the fungus Phellinus weirii. Fortunately this fungus spreads rather slowly and apparently only via root interaction from one infected tree to another, but can remain in the dead or downed wood for a long time. An issue foresters must keep an eye on and in this case will influence reforestation decisions. It can readily be seen that this fungus takes a bit of value out of the timber by turning significant amounts of the lumber into mush.