Abstract
Effects of wrenching Douglas-fir seedlings in August of their second season in the D. L. Phipps State Forest Nursery, Elkton, Oregon, were determined by periodic samplings to learn of changes in phenological, morphological, and growth characteristics. Initial effects of wrenching moderated by January when seedlings were lifted; both wrenched and unwrenched seedlings had grown substantially larger. Survival and growth of seedlings were good during the first 5 years after outplanting in droughty skeletal soil on southeast and northeast slopes in the South Umpqua River drainage of southwestern Oregon, and no significant differences were found between wrenched and unwrenched seedlings. A difference in total tree height on the two slopes was caused by greater browsing on the southeast slope.
Keywords
Regeneration,
wrenching,
nursery practices,
seedling growth,
browsing (-regeneration,
Douglas-fir,
Pseudotsuga menziesfi
Citation
Stein, William I. 1984. Wrenching Douglas-fir seedlings in August: immediate but no lasting effects. Res. Pap. PNW-RP-317.Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Forest and Range Experiment Station. 12 p.