During presettlement times, fire-sensitive species such as Tsuga canadensis and Picea rubens appear to have been most common in low protected areas of the central uplands (Foster and Zebryk 1993), while species such as Quercus rubra and Castanea dentata may have occurred on drier exposed sites (Whitney 1793).
From 1912 to 1914, the chestnut blight (Endothia parasitica) completely eliminated Castanea dentata from the forest canopy (Kittredge 1917).
Although the stand was described as having "the characteristics of a climax stand" in 1942 (Harvard Forest, unpublished manuscript), the presence of dead Castanea dentata and Betula papyrifera suggest that it has a history of disturbance.
Zone C represents pollen assemblages from the period of Tsuga canadensis dominance in these stands beginning after the decline of Castanea dentata ([similar to]1914).
Early successional to midsuccessional Castanea dentata and Betula are present though not abundant, as is the late-successional Tsuga canadensis.
The start of the period of intensive human disturbance at the site (Zone B), is signaled by a rise in Castanea dentata and Betula along with a further increase in Ambrosia pollen (Fig.
The chestnut blight fungus caused the virtual extinction of the dominant tree, Castanea dentata (American chestnut), which created large gaps in the forest canopy.
rubra seen by Stephenson (1986) and others following the death of Castanea dentata may be a temporary mid-successional transition.
Acer pensylvanicum and Castanea dentata had the greatest number of stems in the TS plot (27% and 23% respectively).
In 1983-1984, Castanea dentata as stump sprouts had the greatest number of stems on the MLBS plot (43%), and Acerpensylvanicum and C.
Castanea dentata was one of the dominant understory tree species on both plots in 1983-1984 (Tables 1 and 2) but was replaced by A.