Potential bioindicator plant species for ambient ozone in forested mountain areas of central Europe

From 1993 to 2000, trees, shrubs, forbs and vines were evaluated for symptoms of probable ozone injury in the vicinity of passive ozone samplers or active ozone monitors in forest condition assessment networks in mostly mountainous regions, principally the Carpathian Mountain Range, in the central European countries Czech Republic, Poland, Romania, Slovakia and Ukraine. Each country was visited at least twice during the time period. Over the course of eight seasons, 29 species of native plants were identified as potential bioindicators of ozone. This is the first report of probable ozone injury on native plants in central Europe. Forbs and shrubs made up the bulk of the species (21 of 29). Potential bioindicators that are widely distributed include the forbs Centaurea nigra, and Impatiens parviflora and the shrubs Alnus incana, Corylus avellana, and Sambucus racemosa. Ozone concentrations in forested areas of central Europe appear to be high enough and of sufficient duration to cause foliar injury on a wide variety of native plants.