Stress Bioindicators in Norway Spruce

At three sites in northern Germany stress bioindicators (acid phosphatase and peroxidase activity) were determined in the needles of healthy and damaged trees. Between heathly and damaged trees at a specific site, differences in the stress bioindicators were shown, but no common pattern between the sites could be found. The study indicates that these bioindictors may be used to show a general stress, but it is difficult to relate them to a specific stress factor.