Abstract
A method for predicting beech seeding based on fallen male inflorescence number was evaluated in Hokuriku district, Japan. Flowering and seeding was investigated for 7∼13 years at five stands in disjunct populations and nine stands in continuously distributed populations. It was demonstrated that female flower production can be estimated from fallen male inflorescence number from May to June. Also, it was possible to predict the proportion of filled seeds using estimates of female flower production in the current and previous year. However, Hokuriku district differed from Hokkaido and Tohoku districts in the minimum value of female flower production for mast seeding. In the disjunct populations, the proportions of empty and immature seeds were high, as a result of pollen limitation owing to reduced population size and/or low genetic diversity. Therefore, it is suggested that an equation for estimating the proportion of filled seeds should be formulated for each area and in each population classified by continuity of distribution. The effectiveness of the prediction method was verified by the approximate correspondence between the crops estimated from fallen male inflorescence number and the actual crops. This method is suitable for predicting seed crops until early summer and, for example, may be useful for assessing whether seeds can be collected in autumn.
