Influence of date of cone collection on Douglas-fir seed processing and germination
Subtitle: a case history
By: Donald L. Olson, Roy R. Silen.
Series: Research paper PNW -- 190.; Research paper PNW -- 190.
Publisher: Pacific Northwest Forest and Range Experiment Station, Forest Service, U.S. Dept. of Agriculture
Published: 1975
Place of publication: Portland, Or
Language: eng
Number of pages: 10
Subjects: Douglas fir -- Seeds
Notes: Cover title.

Includes bibliographical references.