ESTABLISHMENT OF SALMONBERRY, SALAL, VINE MAPLE, AND BIGLEAF MAPLE SEEDLINGS IN THE COASTAL FORESTS OF OREGON

To identify seedling regeneration niches for four coastal Oregon shrub and hardwood species (salmonberry (Rubus spectabilis Pursh), salal (G aultheria shallon Pursh), vine maple (Acer circinatum Pursh), and bigl eaf maple (Acer macrophyllum Pursh)) we studied the seed predation, em ergence, survival, and growth of these species on disturbed and undist urbed soil in thinned, unthinned, and clear-cut conifer stands on two sites in the Oregon Coast Ranges. For all species, seedling emergence and survival were greater in thinned stands than in clearcuts or unthi nned stands. In addition, emergence of salmonberry and salal was great er on mineral soil than on soil in which the organic layers were intac t. After four years, height of salmonberry was greatest in the clearcu ts, where it averaged 23 cm. Bigleaf maple and vine maple, which were heavily browsed in the clearcuts, reached their greatest height in the thinned stands, averaging 16 and 15 cm, respectively. Salal seedlings survived only in thinned stands and grew slowly, reaching a height of only 4-5 cm in 4 years. Seedling emergence and predation both were re lated to seed size. On both disturbed and undisturbed soil, vine and b igleaf maple, the species with the largest seeds, had the highest rate s of emergence but also the highest rates of seed predation among the four species.