Search

Search Results

• 1. [Article] Production and costs of cut-to-length thinning : experience from the Willamette Young Stand Project

  Young Douglas-fir stands were commercially thinned to achieve vegetation- and wildlife-related objectives. Harvesting and forwarding production and costs were compared among three mechanized thinning treatments: ...

  Citation × Citation Citation Abstract Copy Title: Production and costs of cut-to-length thinning : experience from the Willamette Young Stand Project Author: Oregon State University. Forest Research Laboratory, Spong, Ben, Kellogg, L. D. (Loren D.) Young Douglas-fir stands were commercially thinned to achieve vegetation- and wildlife-related objectives. Harvesting and forwarding production and costs were compared among three mechanized thinning treatments: light thin [(115 residual trees per acre (tpa)], light thin with 0.5-ac openings (92 residual tpa), and heavy thin (53 residual tpa). The sites were 40- to 50-yr-old stands in the Willamette National Forest in the Cascade Mountains of central western Oregon. Using multiple linear regression equations with indicator variables, we compared both harvesting and forwarding cycle times among treatments. We conducted detailed time studies on a harvester and a forwarder and used these data to develop two regression equations to predict delay-free harvest cycle times and delay-free forwarding cycle times. Delay information was gathered from both shift-level and detailed time studies. Total costs for each treatment were obtained by combining costs for harvesting, forwarding, and moving equipment in and out for the entire operation. Harvesting and forwarding costs did not differ significantly between light and heavy treatments, but were higher in the light-thin-with- openings treatment. Total thinning costs among the three treatments ranged from $28.08 to $34.62/100 ft³. Title: Production and costs of cut-to-length thinning : experience from the Willamette Young Stand Project Author: Oregon State University. Forest Research Laboratory, Spong, Ben, Kellogg, L. D. (Loren D.) Young Douglas-fir stands were commercially thinned to achieve vegetation- and wildlife-related objectives. Harvesting and forwarding production and costs were compared among three mechanized thinning treatments: light thin [(115 residual trees per acre (tpa)], light thin with 0.5-ac openings (92 residual tpa), and heavy thin (53 residual tpa). The sites were 40- to 50-yr-old stands in the Willamette National Forest in the Cascade Mountains of central western Oregon. Using multiple linear regression equations with indicator variables, we compared both harvesting and forwarding cycle times among treatments. We conducted detailed time studies on a harvester and a forwarder and used these data to develop two regression equations to predict delay-free harvest cycle times and delay-free forwarding cycle times. Delay information was gathered from both shift-level and detailed time studies. Total costs for each treatment were obtained by combining costs for harvesting, forwarding, and moving equipment in and out for the entire operation. Harvesting and forwarding costs did not differ significantly between light and heavy treatments, but were higher in the light-thin-with- openings treatment. Total thinning costs among the three treatments ranged from $28.08 to $34.62/100 ft³. Close

• 2. [Article] Tractor thinning productivity and costs : experience from the Willamette Young Stand Project

  Harvesting productivity rates and costs were determined for three silvicultural treatments used in commercial ground-based thinning of young stands to achieve timber management objectives and enhance wildlife ...

  Citation × Citation Citation Abstract Copy Title: Tractor thinning productivity and costs : experience from the Willamette Young Stand Project Author: Oregon State University. Forest Research Laboratory, Davis, Chad T. (Chad Thomas), Kellogg, L. D. (Loren D.) Harvesting productivity rates and costs were determined for three silvicultural treatments used in commercial ground-based thinning of young stands to achieve timber management objectives and enhance wildlife habitat. Treatment definitions were based on residual trees per acre (tpa) after thinning. The treatments were light thin (115 residual tpa), light thin with 0.5-ac openings (92 residual tpa), and heavy thin (53 residual tpa). The three study sites were 44- to 46- yr-old stands of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] located in the Cascade Mountains of west central Oregon. Detailed time studies were conducted on timber fallers and crawler tractors and used to develop multiple linear regression models to predict delay-free felling and skidding cycle times for each site. The independent variables common to the regression models to determine delay-free felling cycle time at all sites were diameter at breast height, number of cuts, and number of limbs cut. Only skidding distance was common to all regression models for determining delay-free skidding cycle time. Total costs for each treatment were obtained by combining felling, skidding, and moving costs for the entire operation. Felling costs ranged from $7.20/CCF to $17.73/CCF. Skidding and loading costs ranged from $15.42/CCF to $38.69/ CCF. The cost and productivity results from this study emphasize the importance for forest managers to consider factors such as volume removed and skidding distance when prescribing alternative silvicultural treatments for young Douglas-fir stands. Title: Tractor thinning productivity and costs : experience from the Willamette Young Stand Project Author: Oregon State University. Forest Research Laboratory, Davis, Chad T. (Chad Thomas), Kellogg, L. D. (Loren D.) Harvesting productivity rates and costs were determined for three silvicultural treatments used in commercial ground-based thinning of young stands to achieve timber management objectives and enhance wildlife habitat. Treatment definitions were based on residual trees per acre (tpa) after thinning. The treatments were light thin (115 residual tpa), light thin with 0.5-ac openings (92 residual tpa), and heavy thin (53 residual tpa). The three study sites were 44- to 46- yr-old stands of Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] located in the Cascade Mountains of west central Oregon. Detailed time studies were conducted on timber fallers and crawler tractors and used to develop multiple linear regression models to predict delay-free felling and skidding cycle times for each site. The independent variables common to the regression models to determine delay-free felling cycle time at all sites were diameter at breast height, number of cuts, and number of limbs cut. Only skidding distance was common to all regression models for determining delay-free skidding cycle time. Total costs for each treatment were obtained by combining felling, skidding, and moving costs for the entire operation. Felling costs ranged from $7.20/CCF to $17.73/CCF. Skidding and loading costs ranged from $15.42/CCF to $38.69/ CCF. The cost and productivity results from this study emphasize the importance for forest managers to consider factors such as volume removed and skidding distance when prescribing alternative silvicultural treatments for young Douglas-fir stands. Close