Abstract

Between 1954 and 1963 cone production of individual trees and seedfall were measured in a mature white spruce stand at the Riding Mountain Forest Experimental Area in Manitoba.Results showed that dominant and co-dominant trees produced heavier cone crops and produced them more frequently than intermediates; intermediates produced heavier and more frequent cone crops than suppressed trees.Over the ten-year period 11.7 million white spruce seed fell per acre, of which 6.7 million were sound. Total annual recorded seedfall varied with a high of 5,625,000 seeds per acre in 1960 and a low of 10,000 per acre in 1958. Seed soundness was highest in years of heavy seedfall and lowest in years of nil and light seedfall.Seedfall generally began in early August with peak seedfall occuring in late August or early September. However, in several years below average air temperatures and sunshine and above average precipitation delayed peak seedfall until late September. Early- and late-falling seed was not as sound as that which fell during the period of peak seedfall.