Germination and early growth of coastal tree species on organic seed beds.

Abstract

Germination and early growth on rotten wood and duff under several shade levels were observed for Douglas-fir, Sitka spruce, western hemlock, western redcedar, lodgepole pine, Pacific silver fir, and red alder. Nutrients were more abundant in duff than in rotten wood. Seedlings usually were larger and more abundant on duff-covered rotten logs than on duff-covered mineral soil under dense coastal stands. Duff accumulations were thicker on logs and over rotten wood embedded in the soil than over mineral soil alone. Shade limited root growth more than height growth, and seed bed differences limited height growth more than root growth. All conifer species responded similarly to the seed bed and shade differences tested, and type of organic seed bed probably does not affect species composition of forest regeneration under lightly thinned shelterwoods in coastal Oregon. Preserving duff accumulations under shaded conditions benefits early growth of all conifer species.

Citation

Minore, Don. 1972. Germination and early growth of coastal tree species on organic seed beds. Res. Pap. PNW-RP-135. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 21 p