Our Local Habitats
By James Nordgren
WHAT ARE HABITATS?:
Habitats are the particular places where animals and plants live and interact together. Just as some people prefer to live in the country or in the city, many plants and animals can only thrive in a certain type of place. An elm tree needs wet soil, a bluebird must have a field, a pileated woodpecker must have a mature forest and so on.
The type of habitat is determined by many factors including whether the soil is wet or dry, the amount of sunlight available, the underlying rock–hard granite or soft limestone, the location–high on a hilltop or down in a valley–and the land’s previous usage–whether it was farmland, whether it was logged, or whether it is residential.
Lewisboro was once entirely forested except for patches of open field caused by fire and wetlands and ponds which were expanded by beaver dams. Although it is hard to believe, by 1800 most of Lewisboro’s forests had been cut down and replaced by farms. In 1820 so many trees had been cleared that there was no shade anywhere along the route from Boston to New York. But by the mid-1800’s farming here became uneconomical and as farms were abandoned, the forests began to re-grow. Today, 70% of New York is once again forest, what some call ‘the great environmental story of the United States’ . These new forests provide us with beauty and recreation, clean air and water, flood control, erosion prevention, carbon sequestration, cooler temperatures and habitat for other plants, insects, birds and other wildlife.
Along with the new forests came wildlife. The naturalist Henry David Thoreau noted that by 1855 bear, deer, beaver and turkey had completely disappeared from Massachusetts–all have returned to Lewisboro along with several new species such as the coyote and fisher.
Today’s habitat is also influenced by events that began long before humans lived in Lewisboro. Millions of years ago, lava from volcanoes, under pressure, formed the granite that is today our ridges and hilltops. Incredibly, the bones of fish and other ocean organisms formed, layer upon layer over eons, the limestone and marble that now underlay our wetlands and the aquifers that provide us with well water. Ten thousand years ago glaciers melted, leaving the scoured ridges that run north to south through the eastern half of Lewisboro and the east to west in the western half of town. The glaciers gouged the softer limestone rock, forming the valleys, streams and wetlands along Route 35, Route 138 and Nash Road.
Other significant landscape features in and around Lewisboro are man-made. We are fortunate to be surrounded to the north, west and south by large County parks–Ward Pound Ridge Reservation and Mountain Lakes Camp–and by drinking water reservoirs–the Cross River and Muscoot Reservoirs-a total of approximately 7,000 acres of open space for plant and wildlife habitat, wildlife corridors, migratory bird stop-over sites and people’s scenic and recreational enjoyment.
The result is a landscape of trees, fields and water bodies that are among the most beautiful in the world. Here the two great forests of the eastern United States–the southern oak-hickory hardwood forest and the northern maple-beech hardwood forest–over lap. Rather than being dominated by a single tree species, our forests have an even mixture of oaks, maples, hickories, beech, birches, ashes, cherries and others. This makes our autumn foliage more brilliant and since so many insects rely on certain types of trees, the varied forest supports equally varied insects which in turn support a wider variety of birds and other animals, leading to some of the highest levels of biodiversity found anywhere in the northeastern United States . And since human health is linked to the level of overall biodiversity, we are all so much the better.