Fifty red alder communities from 1 to 65 years old were studied in western Oregon. Highly significant correlations were found between an index of volume and dry weights of whole trees, individual stems, crowns, tops, and roots. Correlations of dry weight with other independent variables (age, dbh, height) were variable and strongly curvilinear. Ratios of crown to stem in dominant trees were
... [Show full abstract] higher than those of suppressed or intermediate trees. Biomass of aboveground parts increased rapidly during the first 20 years and of maximum growth (between 10 and 15 years) averaged 26 mt/ha per year. Net assimilation rates ranged from 2.58 to 4.33 mt/mt per year. To produced best yields, red alder stands should be harvested for 20 years of age.