EN
Tending operations were carried out in about 20 year old silver fir upgrowth in 1983 and 1989. They were evaluated in 1995 when different biomorphological characteristics of young firs were analysed. The operations based on the positive selection stopped the process of crown reduction and resulted in increased diameter increment. In case of firs in the lower tree layer they also resulted in increased height increment. Trees in the combined variant reacted with increased diameter increment and formed longer crowns. However, the combined treatment led to disappearance of natural height differentiation of the upgrowth and simplification of its structure which in consequence reduced its potentiality for practical utilisation. The negative selection in comparison with the control variant had no significant effect on the biomorphological characteristics of tree.