Factors influencing initial sprouting of red alder

Two studies were established to investigate factors influencing sprouting of red alder (Alnusrubra Bong.). In the first study, 4-year-old planted trees were cut at five stump heights (0, 10, 30, 50, and 70 cm) during 4 months of the year (January, May, July, and September). The percent of stumps surviving was greatest with cuts in January at 30 cm or higher; survival was least with 0- and 10-cm cuts during July and September. In the second study, 29 natural stands varying in age from 1 to 32 years were cut in February. Sprouting was most vigorous and consistent in very young stands. Few stumps sprouted in the oldest stands; in addition, the older stands had fewer sprouts per stump and the sprouts were shorter. Stumps with a level surface had the greatest mortality and were least likely to sprout; stumps with the cut surface facing south or west had the least mortality and were most likely to sprout. Based on the results from both studies, specific cutting practices are recommended to achieve different management objectives.