Laminated Root Rot Tree Disease

Laminated root rot should be considered a disease of the site.

Laminated root rot tree disease. Surveys indicate approximately 5 of the area of highly susceptible host types in oregon and washington is out of production because of this disease. It does not spread through uncolonized dead wood but may infect a live root that grows into contact with infected dead wood. That is established mycelia of this fungus are essentially permanent so the best course is to minimize losses by managing tree species that can be expected to have better survival on infested sites. Laminated root rot is a typical root and butt rot.

Laminated root rot is one of the most damaging root disease amongst conifers in northwestern america and true firs douglas fir mountain hemlock and western hemlock are highly susceptible to infection with p. Laminated root rot attacks and kills a tree s root system. Distribution of laminated root rot in western north america root diseases among the greatest mortality risks to forests in the u s predicted to cause more than 1 billion ft2 of mortality over 15 years 2013 2027. A few species of plants such as western white pine and lodgepole pine are tolerant to the pathogen while ponderosa pine is resistant to it.

Trees affected by root disease are also more susceptible to bark beetles and wood borers and are more likely to fall during a storm or high winds. Laminated root rot laminated root rot caused by the fungus phellinus poria weirii is responsible for an annual estimated volume loss of 32 million cubic feet in the west side douglas fir type. Laminated root rot is the most damaging root disease in oregon from the stand point of wood fiber produc tion. It leads to expanding centers of mortality.

Laminated root rot caused by the fungus phellinus weirii is the most damaging root disease in the pacific northwest and one of the most difficult to control. This hinders its ability to suck up water and soil nutrients. Laminated root rot spreads primarily through root to root contact between infected and uninfected host trees. This native root pathogen is often found in forested areas in large old tree stumps where it can live several decades as a saprophyte.

It is estimated to cause annual losses of 32 million cubic feet of wood in western oregon and washington and may cause equally staggering losses in the eastern portions of both states. Sulphurascens in some reports. It affects all conifer species to some degree but is most damaging to douglas fir grand and white fir and mountain hemlock table 2 page 4. It successfully infects host trees regardless of their vigor.

Laminated root rot also known as yellow ring rot is caused by the fungal pathogen phellinus weirii. Only hardwoods are known to be immune to. Found in western and eastern oregon the disease is caused by the fungus phellinus weirii. Fir douglas and true laminated root rot cause coniferiporia weirii formerly phellinus weirii a fungus may also be called p.