The Hohenheim long-term experiment: a North American perspective.

The Hohenheim experiment represents a five year multi-disciplinary study of tree sapling responses to O(3), SO(2) and simulated acidic rain singly or in combination in modified open-top chambers. There are no comparable studies in North America which have been brought to completion at the present time. However, many of the results obtained in the Hohenheim study can be examined in the context of North American research. Independent of the differences in the methodology, the experimental conditions and the tree species used, many results are quite comparable between the Hohenheim study and the findings of North American research. However, since comparisons were made with studies in chambers of various types, caution must be used in extrapolating the results in addressing questions in the chamberless ambient conditions.