Sprouting Ability and Significance for Coppicing of Dormant Buds on Betula pubescens Ehrh. Stumps

The numbers of basal dormant buds and resulting sprouts and their distribution on the stumps of the trees were studied in specimens of Betula pubescens Ehrh. of vegetative and seedling origin of different ages and growing on peatland or mineral soil. The results suggest that the number of buds at the base of the tree varies markedly from one tree to another. The old and young trees had quite similar numbers of buds, but those on mineral soil had less than those growing on peatland. The highest numbers of basal buds were found on sprout-origin trees. Although about 90% of the basal buds were found below ground level, 1/3 of the sprouts originated from above the ground. This discrepancy can be explained by the formation of bud clusters, since the majority of the sprouts were derived from buds which occurred singly or in very small clusters. The total number of basal buds explains only part of the observed variation in sprouting potential. More important is the formation of bud clusters during the maturation of the tree. The old stumps gave the poorest sprouting results, because their buds were located principally in large clusters. Similarly less sprouts developed on peat soil than on stumps of a corresponding type on mineral soil. The best sprouting ability was observed on the stumps of the trees which had themselves developed vegetatively. The results suggest that sprouting success can be predicted when the location of the buds on the stump is known.