Drought affects trees: Already leaves and discoloration
environment
The drought affects the native trees, reports the Federal Research Center for Forests. In Salzburg, trees in the Flachgau are particularly affected. In response to the drought, some deciduous trees have been dropping their leaves since July.
Because of the water absorption, many leaves are already discoloring or falling off. The experts at the Federal Forest Research Center (BFW) warn that the drought also makes the trees more susceptible to fungi or bark beetle infestation. Across Austria, the drought is having the greatest impact on trees around Vienna and in the Innviertel (Upper Austria).
Trees shed leaves as the first reaction
Anyone who is currently in the local forests can observe how a relatively large amount of leaves are already covering the ground. Bernhard Perny from the BFW emphasized that this is still a reaction to the increasing drought and high temperatures and not already a sign of a change-related shift in the vegetation phases. The partly plant-like appearance is primarily a reaction to the lack of water. This is first indicated by the fact that the trees close the stomata on the leaves and reduce photosynthesis.
Increased leaf fall and discoloration since July
Increasing discoloration of the leaves and increased leaf fall has been observed in some tree species since July. This applies to the beech, for example, although it has deeper roots than the shallow-rooted spruce. The somewhat strange effect is related to the fact that the spruce can make better use of the rain that has just fallen. The deeper-rooted deciduous tree, on the other hand, feels the lack of water at particularly low altitudes. In the longer term, however, the spruce, which is not adapted to the high temperatures, naturally suffers significantly more from the drought.
First consequences visible in spring
Researchers say the first consequences will probably become more visible next spring. In the short term, foresters cannot do anything about drought damage. However, according to the experts at the Federal Research Center for Forests, one should probably rely on more species-rich mixed forests.