Three hundred years of forest and land-use change in Massachusetts, USA

Aim The aim of this study was to document changes in forest composition, structure and distribution across Massachusetts, USA, from the time of European settlement (seventeenth century) to the present, and to investigate environmental and historical influences on regional patterns of variation. Location The study area encompasses the State of Massachusetts (69.9–73.5 E, 41.3– 42.9 N), a 21,000-km area in the north-eastern United States. Methods A wide range of historical sources was used to document changes in land use and land cover for the historical period. Witness trees from early land surveys enabled us to evaluate vegetation patterns prior to widespread European settlement, and to compare historical and modern species composition. Nineteenth century maps of forest cover and contemporary agricultural censuses documented forest patterns during the peak agricultural period. Geographic Information System analyses were used to relate variation in climate, geology and land-use history to historical and modern forest composition. Results Massachusetts has a complex east-to-west environmental gradient involving changes in physiography, climate, geology and natural disturbance. Until the middle of the twentieth century, agriculture was the most important land-use across the region; although the percentage of land in agriculture and the timing of major land-use changes were remarkably consistent across the state, historical forest patch sizes varied locally and regionally in relation to physiography. Forest composition of both early historical and modern forests is most strongly related to environmental conditions, especially variation in climate. Historical land-use resulted in a state-wide increase in early successional tree species and a dramatic, although recovering, change in forest structure. Main conclusions At a regional scale, environmental conditions apparently control broad patterns of variation in vegetation composition. Historical land-use practices were relatively homogenous across Massachusetts and local variation was reduced through data averaging at broad spatial scales. At finer spatial scales, historical land-use has strong and persistent impacts on vegetation composition and structure.