HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Heilman, P. Search for Related Content PubMed Articles by Heilman, P. Agricola Articles by Heilman, P.

Effects of Surface Treatment and Interplanting of Shrub Alder on Growth of Douglas-fir on Coal Spoils¹

ABSTRACT

Annual growth of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) planted on topsoiled spoils at a coal mine near Centralia, Wash., was monitored for the first 5 y after planting. Treatments were contour bedding, contour bedding plus interplanted Sitka alder (Alnus sinuata (Reg.) Rydb.), and unbedded control. The bedding significantly increased growth of Douglas-fir in all 5 y of the study. Total height growth after 5 y was 35% greater than control on the bedding only plots, and 43% greater on the bedding plus Sitka alder plots. Height growth of Douglas-fir in the mixed stand was significantly greater during the 2nd and 3rd y of the study, but after 5 y, no significant difference was evident in total height between the mixed and pure Douglas-fir plots. Concentration of N in Douglas-fir foliage was significantly increased by bedding in the fifth but not in the fourth year. Interplanting with Sitka alder had no significant effect on N in Douglas-fir foliage.

The top 0.3 m of soil in the ridged portion of the bedded area contained significantly less moisture over a summer than did the top 0.3 m of the unbedded soil. At deeper depths, however, soil moisture was not significantly affected by bedding.

Wind damage caused by a severe storm that occurred after 5 y was very much greater on the unbedded plots (49% wind-thrown vs. 9 to 15% wind-thrown on the bedded plots) despite the smaller size of the trees on unbedded plots.

Key Words: Pseudotsuga menziesii • Alnus sinuata • bedding • topsoil replacement • foliar N • soil N • spoil moisture • wind damage

¹ Contribution from Washington State University College of Agriculture Research Center, Pullman, WA 99164. Scientific Paper no. 6216. Project 0531. This research was partly funded by a grant from Washington Irrigation Development Company (WIDCO), Centralia, WA.

² Forest Scientist, Western Washington Research and Extension Center, Puyallup, WA 98371.

Received for publication April 16, 1982.