Reduced Volume, Grade and Value of Lodgepole Pine Lumber Caused by Atropellis Canker and Stalactiform Blister Rust

Abstract

In a stand of 45-65-year old lodgepole pine, Pinus contorta Dougl. var. latifolia Engelm., in the interior of British Columbia, Atropellis canker, Atropellis piniphila (Weir) Lohman and Cash, and stalactiform blister rust, Cronartium coleosporioides Arth., reduced the volume of infected trees by 7.9% and 6.2%, respectively. Manufacture of lumber from these trees increased volume losses by up to 28.7% and 26.4%, respectively. Atropellis canker reduced the volume of Standard and Better grade lumber by up to 40.1% and stalactiform blister rust by 33.3%, with corresponding relative increases in the volume of Utility grade up to 80%. The reduction of lumber volume and grade decreased the value of Atropellis-infected trees by 33.4% and stalactiform blister rust-infected trees by 28.7%. Based on the density of stems per hectare and infection rates, the two diseases reduced the potential lumber value of lodgepole pine by $508.40 per hectare. Thus management measures to reduce the incidence and impact of these diseases may be economically justified. Key Words: Lodgepole pine; Pinus contorta; Atropellis piniphila, Cronartium coleosporioides; lumber volume, grade, value.