Effects of environment and land-use history on upland forests of the Cary Arboretum, Hudson Valley, New York

Relationships of vegetation to environment and land-use history were investigated in fbrests of the Mary Flagler Cary Arboretum in the Hudson Valley of New York. Vegetation data were obtained from 76 1/4 ha circular plots randomly located within the forest. Environmental data collected at each plot included slope, aspect, canopy openness, soil texture and nutrients, topographic position, and presence of exposed rock; gravimetric soil moisture was determined weekly during 1985 for a subsample of 25 stands. Land-use history information came from historical records (land deeds and U.S. and N.Y.S. census records), stone-fence locations, landscape patterns in stand ages, an old aerial photograph, and soils data. Vegetation analyses identified three major community types. One group of stands, dominated by chestnut oak (Quercus prinus L.) and northern red oak (Quercus rubra L.), occurred on steep, rocky, upper slope sites never cleared for agriculture. Distinct vertical stratification of dominant canopy species in these stands is consistent with a probable history of intensive selective cutting early in this century. Both of the other major community types occurred primarily on abandoned agricultural land. Stands dominated by white oak (Quercus alba L.), black oak (Quercus velutina Lam.) and pignut hickory (Carya glabra (Mill.) Sweet) tended to occur at lower elevations on rocky, nutrient poor sites probably derived from abandoned pastures. The significantly more open canopy in these stands, less distinct vertical stratification of canopy trees, and a diverse herbaceous understory frequently including grasses and sedges, also suggests very gradual invasion of these forests onto old pasture sites. The third major vegetation type, dominated by red maple (Acer rubrum L.) and white pine (Pinus strobus L.), tended to occur on finer textured, less rocky old field sites possibly abandoned from cultivation. Comparison of current vegetation with witness tree data from early land survey records suggests that the white oak-black oakhickory type was prevalent on lower slope sites prior to forest cleating, but has declined in importance relative to the red maple type during the past 100 years of abandonment of land from agriculture.