Vegetation of the presettlement forests of Northern New England and New York

摘要

The lotting surveys from northern New England and New York provide a unique opportunity to derive quantitative documentary evidence on past forests. Due to the distinctive "proprietory town" land tenure system, northern New England has an extensive and virtually untapped archive of land division surveys done prior to settlement (1763-1820). I searched archives throughout Vermont, New Hampshire, and northern New York and located records from 179 towns documenting 48,260 individual trees across the region. Surveyors used 131 separate vernacular names representing at least 49 recognizable species. This collection of town-wide witness tree relative frequencies is a consistent and unbiased empirical estimate of the composition of the natural vegetation before confounding land use. Five ubiquitous taxa (beech, spruces, maples, hemlock, birches) comprised 79% of the witness trees. Beech (32%) consistently dominated the region with greater than 60% of the trees in some towns. Spruce (14%) was the second most abundant species and found throughout the region. Maples (12%) were consistently distributed with peak abundance in Vermont. Hemlock (12%) had a patchy distribution with pockets of abundance, including the eastern Adirondacks. Birches (9%) were a species group with higher abundance in the mountains or to the north. White pine was consistently uncommon with very low (<1%) abundance on the uplands. A dramatic "oak-beech" tension zone or ecotone separated the oak-pine vegetation in the major southern valleys from the spruce-maple-beech composition northward. The central tendency was toward spruce-hardwoods with distinctive variants in the north, the Taconics, and the Champlain Valley. Major fires and blowdowns were equally rare and affected only 0.5% of the region. Fire was frequent only in the Hudson-Champlain corridor and windthrow was a lowlevel background disturbance. The most dramatic changes documented over the past 200 years have been the decline of beech and the profound effects of human land use.