First Year Results of a Program for Monitoring the Health of Whitebark Pine (Pinus albicaulis) at Crater Lake National Park

Donahue, Jacquelien

Whitebark pine trees are an important wildlife resource and early-seral species in alpine ecosystems that are in decline throughout their range in the United States and Canada due to white pine blister rust, a disease caused by the exotic fungus Cronartium ribicola. Objectives of the Crater Lake National Park study included: (1) Determine the health of whitebark pine stands with emphasis on measuring blister rust infection, (2) determine composition and cover of Ribes species within stands (the alternate host for C. ribicola), and (3) establish a network of plots to monitor the health of whitebark pines. A stratified random sample of whitebark pines in the vincity of Mt. Scott showed : (1) no blister rust detected in the sample units, (2) 4% mortality of P. albicaulis, and (3) no Ribes present in sample units. Possible reasons for the finding of no blister rust include climactic factors and small sample area.