On the Reproduction of Aspen (Populus tremula L.) with Emphasis on Its Suckering Ability

Numerical data are presented that support the proposal mentioned as early as the mid-19th century that aspen roots may remain alive for a long period after the disappearance of parent trees. The mechanism that makes this possible is the ability of this species to form suckers continuously. In stands the bulk of the suckers live a few years and are then replaced by new ones. If conditions allow some suckers may develop into big trees even in old stands. The conclusions are based on material obtained in experiments comprising chemical control of aspen, including different application methods, herbicides, doses and in some cases control treatment (cleaning).