By the middle of the 19^th century, nearly all of central Massachusetts, USA, was cut at least once and 80% deforested. When did deforestation begin? We recorded all the trees and other corner markers used in 18^th century proprietors' surveys of Shrewsbury, MA. From 1718–1799, the percentage of corner markers that were “trees” declined from 45% to 20%, and the relative abundance of white oak tended to decrease. Unexpectedly, the relative abundance of white pine more than doubled. Overall, deforestation and alteration of species composition were already occurring in the 18^th century due to changing conditions, selective harvest, and differences in the resilience of the dominant trees. Proprietors' records can provide data on forest change as well as forest composition.