Yesterday I visited a stand on the Clearwater NF where it appears that H. irregulare is killing ponderosa and lodgepole pine. Expanding infection centers of pole to mature pines around large resinous pine stumps that look like they are about 50 years since cutting, pine decay, white/tan ectotrophic mycelium on roots of affected pines while Douglas-fir and grand fir ingrowth are unaffected by root disease fits well with this guess. I could not find any conks but will be attempting some isolations from the wood and ectotrophic mycelium to see what comes out.

 

The district silviculturist had been planning a regeneration harvest and regenerating by planting western larch/western white pine. Does anyone have any recent references on which Heterobasidion species and what severity can be expected on western white pine? I seem to recall that western white can act differently than hard pines but I haven’t been able to pull much information together yet.

 

Thanks!

 

 

Paul Zambino, PhD Plant Pathologist Forest Service Region 1 Forest Health Protection, Coeur d'Alene Field Office p: 208-765-7493 c: 208-446-4251 f: 208-765-7307 pzambino@fs.fed.us 3815 N Schreiber Way Coeur d'Alene, ID 83815 www.fs.fed.us Caring for the land and serving people