Demography of a clonal shrub, Alnus incana ssp. rugosa ( Betulaceae).

Size-specific rates of stem mortality, diameter growth and sprout production were measured for speckled alder in central New York sate. Stems in smaller size classes varied more in mortality and growth than did larger stems. Variation in demographic rates within a population, either from year to year or from place to place, was often as great or greater than the variation between sites. Basal sprout production may be sufficient for long-term persistence of individual clumps and of entire populations.-from Author