Windschur oder Salzschur?

Untersuchungen über Ursachen von Kronendeformationen

Abstract

The real cause of the deformation of tree tops along the coast is not the wind but the salt of seawater spray. This was clearly proved by a rainless gale which lasted for several of the last days of May, 1972. The leaves of the trees exposed to the wind changed colour within a short time and were thrown off. Similar observations may be made every year through the entire vegetative period. Along the exposed side the leaves change colour, fade and the branches dry up along the side protected from the wind the trees and bushes thrive undisturbed. By a chemical analysis eighteen times as much salt was found on the exposed side as on the protected side. With a spraybox the same change may be simulated and the same damage results. These observations were confirmed by numerous experiments in protected places on the isle of Fohr and in the Taunus region. According to the wind tunnel investigations of Tranquillini there is no physiological influence of the wind on trees. Rain may take the salt out of the air or from the leaves and diminish the damage. That is why under the same wind conditions quite different tree-top deformations result which prove nothing in bioclimatological investigations. In coping with problems of wind protection such observations should also be taken into consideration.