Growth of the non-native Pinus nigra in four habitats on the sand dunes ofLake Michigan

We examined the post-planting success of the non-native Pinus nigra Arnold (Austrian pine) in four habitats in a Lake Michigan sand dune system, into which approximately 26 000 seedlings had been introduced between 1956 and 1 972. Growth (height, diameter, and stem volume) of P. nigra on the dunes wa s compared to that of individuals of similar age in managed plantations and in the native European range. Tree size differed more within than among du ne habitats, indicating that the coarse-scale differences in environmental factors among habitats, such as distance from the lake, soil moisture, and wind exposure, account for only some of the variation in growth. Comparison s with native European populations indicate that P. nigra grows as well or better on the dunes of southern Lake Michigan than in its native range. The broad ecological tolerance of P. nigra appears to be a major attribute in its successful establishment in a variety of dune conditions. (C) 2000 Else vier Science B.V. All rights reserved.