Morphological changes in the crowns of European beech (Fagus sylvatica L.) and other deciduous tree species : Waldschadensforschung - Wissensstand und Perspektiven. Internationaler Kongress

1990

S. 81-107

17 Abb., 29 Lit. Ang.

Unselbständiges Werk

200068528

In the present paper firstly general methodical problems of vitality assessments of deciduous trees are discussed and also existing disparties or contradictions are pointed out also existing disparities or contradictions are pointed out if assessements based on "leaf loss" and those based on crown structures are compared. The necessity of a consideration of branching is substantiated and methods which have been developed until now are presented. Ecological morphology is a new, promising approach to explain modifications of tree growth and crown development and to detect its causes. E.g., by the help of the 'shoot base scars', it becomes possible to reconstruct the crown development over the last ten years, partly over decades. In every investigated (broad leaved) tree species (and in Scotch pine), there are to discriminate four growth phase, which are due to /statistically significant) decreasing shoot lenghts with the result of fundamental midifications of the branching structure. Especially in the leaf-less state, these different branching structures in the very treetop are to perceive from a distance (and in aerial photographs, too) and are the basis of a vitality assessement by four vitality classes, which were developed for 18 hardwoods and Scotch pine. By this approach based upon branching structures, a long-term, chronic decrease of vitality can be recognized. Thereby, it is a practicable method to detect forest decline and to discriminate it from short-term influences, e.g. drought damages. Correlations between structural changes of the crown and radial growth as well as the root development do exist and genetic and silvicultural consequences. Finally, the demand for further action and research requirements is put forward.