Effects of leader topping and branch pruning on efficiency of Douglas-fir cone harvesting with a tree shaker
By: Donald L. Copes
Contributors: Pacific Northwest Forest and Range Experiment Station (Portland, Or.)
Series: Research note PNW -- 431
Publisher: U.S. Dept. of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station
Published: 1985
Place of publication: [Portland, Or.]
Language: eng
Subjects: Conifers -- Seeds -- Harvesting; Douglas fir -- Pruning
Notes: Caption title

Distributed to depository libraries in microfiche

"October 1985."

Bibliography: p. 7-8