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contributed to de-stocking and land abandonment, as sheep farming became uncompetitive
and people moved away to find alternative employment opportunities in trade and industry.
At the same time, the rail network allowed access to produce from farms in the Midwest and
cheap grain was used as cattle feed, feeding a thriving, intensive dairy industry on much less
pasture land. The focus of farming in New England changed from regional self-sufficiency to
producing perishable, high value or bulky items like dairy produce, fruit and vegetables,
poultry, tobacco, and hay. The human population continued to grow, while stock numbers
plummeted and the numbers of livestock declined.
As farms were abandoned, forest cover rebounded (Figure 7.6a-c) (Foster 2003, Foster
et al. 2008). By the 1850s much cleared land was being colonized by red cedar, white pine,
cherry, birch, and red maple. Remote upland farms were abandoned first, while pastures and
fields remained in more accessible areas with richer soils. By 1920, about 50% of the land-
scape of New England was under forest cover. Industrial production peaked in the early
twentieth century, declining from the 1930s to the 1970s due to competition from other
regions, and many industrial sites, in their turn, were abandoned.
Analysis of fossil pollen from coastal New England showed low abundances of grasses and
weedy, disturbance-adapted vegetation prior to European settlement, consistent with the
presence of closed forest (Motzkin and Foster 2002). The abundance of these pollen types
increased dramatically when European clearance of forest for timber and agricultural land
was at its peak, accompanied by increases in early successional and disturbance-adapted
species like birch and red maple. More recently, the abundance of pollen from open vegeta-
tion types has fallen to intermediate levels, indicating a recovery of forest and the abandon-
ment of ploughed and grazed lands (Figure 7.6d).
In lowland areas, the landscapes of New England are a mosaic of forests, heathlands, sand-
plain grasslands, shrublands, open fields, and old field pine stands. Such landscapes are
home to globally rare species that are adapted to open lands, and are highly valued for their
aesthetic appeal and recreational opportunities (Motzkin and Foster 2004). These are cul-
tural landscapes with no past analogue, which will only be sustained in the landscape if
ploughing, grazing, burning, and mowing are reinstated to prevent forest regeneration (Fos-
ter et al. 2002, Motzkin and Foster 2002).
In the early twenty-first century, more than 80% of upland areas are now forested. The nat-
ural patterns of spatial and temporal heterogeneity in forest vegetation were almost entirely
erased over centuries of anthropogenic management, which included cycles of extensive
clearance, agricultural intensification, followed by land abandonment and forest regrowth.
Today's forests are much more homogeneous than those encountered by the settlers, and
present forest composition can be better predicted based on time since disturbance and suc-
cessional stage, than elevation or climate. The post-clearance forests are now maturing,
assisted by declining wood harvesting and the suppression of fire. Although 100 years is a
relatively short period of time in the life of a forest, there is no evidence of progression towards
former forest composition, and some species have failed to regenerate while others are much
more abundant (Motzkin and Foster 2004). The forest assemblage reflects a mixture of early-
and mid-successional species, as well as a greater proportion of fire-sensitive species like
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