DISTURBANCE IN WETLANDS ASSOCIATED WITH COMMERCIAL CRANBERRY (VACCINIUM-MACROCARPON) PRODUCTION

We studied disturbance in 15 palustrine wetland plant communities associated with commercial cranberry (Vaccinium macrocarpon) production in Wisconsin. The importance values (sum or relative frequency and relative cover) of species were correlated with distance from disturbance. Importance values of pteridophytes increased with distance from disturbance. Significant correlations of importance values with distance were detected for 26-31% of species in sedge meadows and 15% of species in bogs, where 10% was expected. Taxa which had high importance values close to the disturbance had affinity for sand and desiccated conditions. Further disturbance should be minimized by designing spatially compact cranberry bed complexes. Roads and dikes should be vegetated to prevent deposition of sand and biocides into the wetland.