Untersuchungen über die Wurzelkonkurrenz : 1. Mitteilung über den Vorwald

A Study about Root Competition in Trees = First communication about the culture of pioneer tree species

Birmensdorf

1958

S. 361-398

9 Abb., 21 Tab., 6 Lit. Ang.

Bandaufführung

1265

157642

Climatic and soil factors complicate the afforestation of denuded areas. For that reason, it was used in Switzerland, some time ago, different tree and shrub species for advance planting. The establishing of such stand dealt with the following questions: +) The influence of pioneer tree species on climatic conditions of the lower air layers near the surface of the soil. +) The influence of pioneer tree species in soil conditions. +) The influence of pioneer tree species on main tree species. The investigation is only a part of a research program about the effects of advance planting upon the first growth of main tree species and light reduction and root competition. It is asserted to be a base for futher inguiries to be undertaken in the field. To answer those questions, experiences were conducted in pots and in ursery. Statistical analysis of the result showed that light reduction and root competition acted simlutaneously, but that root competition is illustrated by a frequent statistically significant different heights growth according to the species. Moreover, the share of root competitionin relation to total competition appeared to be diffrent according to concurrent species studied, and decreased n the following arrangment: birch, whithe alder, aspen. It seemed to be no diffrences at all in the case of light competition between the various tree species tested. In opposition to light, total competition between tree species showed greater differences due primarily to the specific root competition, but results were statistically significant anly when comparing aspen-whithe alder inside a pine stand and aspen-birch inside an oak stand. Very small competition in the case of aspen may be regarded but as a tendency. Concerning the share of root competition in relation to total competition, the various species reacted differently. In the case of half-tolerant surface rooted spruce, root competition seemed to be stronger than for the pine and much more than in the case of oak. About the share of light competition in respect to total competition, only small differences were observed of the reaction of the various species. These experiments show the importance of root competition, not to be neglected in a closed stand composed of the advance planting tree species: whithe alder, birch and aspen inside spruce, pine and oak. Nevertheless, its influence is different according to the used pioneer tree species. In fact, on one side, the space between trees is to be increased oin order to minimize the influence of root competition and, on the other, this space is to be adjusted in order that soil and climatic improving effects may reach their maximum efficiency.