Age distributions are given for four species in a virgin spruce—fir stand in New Hampshire together with comparative data from virgin northern hardwoods. Three distinct forms of age distribution were found: (1) essentially linear relationships of numbers of stems (log) vs. age (log) denoting stationary populations with a power function form of survivorship; (2) concave age distributions indicative of increasing populations; and (3) convex to bell—shaped age distributions reflecting declining populations with a low birth date. Picea rubens, Abies balsamea, Betula papyrifera var. cordifolia, and Sorbus americana all exhibited stationary age distributions in the virgin spruce—fir stand. In virgin northern hardwoods, Fagus grandifolia and Acer saccharum appeared to be stationary or increasing, respectively, while P. rubens and Betula alleghaniensis had age distributions typical of declining populations.