forest dieback. dead trunks of common red spruce trees (picea abies)

tree winter branch plant snow frost spruce flower forest freezing autumn ice nature sunlight twig woodland sky trunk fir climate change dieback tyrol austria trunks common red trees picea abies beetles drought blue cloudless rain catastrophe coniferous covered damage dried forestry frosty future illness parasites waldsterben saurer regen krank vertrocknet trockenheit borkenkäfer schädling naturkatastrophe umwelt umweltschutz umweltschäden klimawandel