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Geomorphology (landforms)
The Section comprises parts of the New England, Piedmont, and Coastal Plain geomorphic provinces. Cape Cod and Long Island are large terminal moraine (glacial debris) complexes modified by coastal processes. Glacial features such as small to large delata plains, lacustrine basins, eskers (gravel ridges), and extensive drumlin (glacial drift mound) fields are widespread. The Section gradually descends in a series of broad, hilly plateaus to the coastal zone. Central Connecticut and western Massachusetts are characterized by a north to south trending basin, a lowland plain, punctuated with a central linear ridge. Primary geomorphic processes are coastal and fluvial erosion, transport and deposition, and mass wasting (landslides). Elevation ranges from sea level to 1,500 ft (450 m). Some high hills (monadnocks) are 2,000 ft (600 m). Local relief ranges from 100 to 1,000 ft (30 to 300 m). Gentle slopes cover less than 20 to 80 percent of the area; 50 to 75 percent are in lowlands. Subenvelop elevation ranges from 0 to 650 ft (0 to 200 m).
Lithology (rock types) and Stratigraphy (rock layer types)
Surficial geology is Pleistocene age. In the northeastern part, coastal lowlands are covered by glacial marine sediment (mostly clay). Thin, stony till (mixed glacial sediment) and glacial fluvial and glacial lacustrine sediment overlie bedrock inland. Cape Cod, Long Island, and Block Island are composed of thick, morainal and outwash (glacier-melt sediment) sediment. The bedrock geology is varied and complex. Intense, northeast to southwest trending, faulting, and folding, and plutonic and volcanic episodes have resulted in variegated sedimentary, igneous, and metamorphic rocks. Triassic-Jurassic red conglomerate, sandstone and shale (the north to south trending lowland), with a prominent diabase sill (the linear ridge); Carboniferous sandstone, conglomerate, shale and dolostone; Paleozoic granites and volcanics; lower Paleozoic and Proterozoic quartzite, marble, schist, gneiss, and greenstone; and massive Proterozoic granite, granodiorite, diabase, and gabbro. Minimum elevations range from about 200 ft (61 m) in the north to near sea level south of Long Island Sound. Maximum local elevations are generally under 500 ft (152 m) but range to 1,000 ft (305 m). Gentle slopes cover 50 to 80 percent of the area; 50 to 75 percent occurs in uplands.
Soil Taxa (groups)
Interior Section taxa include Dystrochrepts and Haplaquepts with udic (perpetually moist) and aquic (saturated) moisture and mesic (avg. 8-15°C) temperature regimes. Coastal regions, (e.g., Cape Cod and Long Island) are characterized by Udorthents and Udipsamments with mesic (avg. 8-15°C) temperature and udic (perpetually moist) moisture regime. Sulfhemists, Sulfaquents, and Medisaprists are also common near coastal areas.
Potential Natural Vegetation
Kuchler vegetation types include northern hardwood, Appalachian oak, and northeastern oak-pine forest. Regionally-defined important vegetation types include northern hardwood-hemlock-white pine, central hardwoods, coastal pitch pine, maritime oak, and maritime red cedar.
Fauna (animals)
Drastic disturbance of the original ecosystems and their faunal component resulted from European settlement. Major predators (e.g., timber wolf) were intentionally exterminated. Other large vertebrates were exterminated (e.g. moose), reduced, or restricted (e.g., white-tailed deer, wild turkey) by hunting and habitat loss. Original distributions were re-established or exceeded for some species with the re-establishment of forests on abandoned agricultural lands, in some cases, with higher population densities. The large predators have not returned; their niche has been partially filled by mid-size predators (e.g., bobcat, coyote). This ecological shift, combined with hunting access restrictions, has resulted in imbalances between herbivores and plant resources. Extensive areas of regenerating forest and associated early successional habitat are lacking. Hard tree mast (i.e., acorns, beechnuts) drives many faunal processes. Common wildlife species include the white-tailed deer, gray squirel, white-footed mouse, red-eyed vireo, and red-spotted newt. Restoration of historical Atlantic salmon in the Connecticut and Merrimack Rivers is ongoing. No Federally listed threatened and endangered species are unique to this area.
Climate
Precipitation, which ranges from 35 to 50 in (820 to 1,270 mm), is evenly distributed throughout the year. Snow increases with elevation; amounts vary from 36 to 100 in (915 to 2,540 mm) of snow increasing with elevation. Mean annual temperature ranges from 45 to 50°F (7 to 10°C). The growing season lasts for 120 to 180 days.
Surface Water Characteristics
Abundant water resources include perennial streams, natural and artificial lakes and ponds, fresh and saltwater wetlands, and estuaries. Streams exhibit deranged, dendritic (branching), and trellis patterns due to a complex geomorphic history of stream imposition, differential weathering, glaciation, continental rebound, and stream capture. Stream gradients are generally low but steepen locally near the Connecticut River and in areas approaching the uplands and mountains. Average annual runoff ranges from 18 to 24 in (460 to 610 mm). Maximum monthly streamflows occur in March and April. Extreme peak flow may occur any time of year and usually are associated with hurricanes or rain-on-snow events. Minimum monthly flows occur in August, September, and October. Most lakes and impoundments are small. The exceptions are Lake Winnipesaukee (72 mi², 186 km²) and Squam Lake (11 mi², 29 km²) in New Hampshire, Sebago Lake (45 mi², 116 km²) in Maine, and the Quabbin Reservoir (37 mi², 96 km²) in Massachusetts.
Disturbance Regimes
Central and coastal New England have intermediate to high occurences of fire and hurricane winds (thirty to fifty years) relative to inland New England sites. Tidal flooding associated with storms occurs along the coast. Regionally, the distribution of modern and pre-settlement forest types match well. At a landscape scale, modern forest characteristics are strongly controlled by land use, particularly agriculture dating from colonial time and subsequent farm abandonment from about 1850. Insect and disease disturbances result from gypsy moth, beech bark disease, chestnut blight, Dutch elm disease, hemlock woolly adelgid, periodic pitch pine and hemlock looper, oak leaf tier damage, and red pine scale and adelgid.
Land Use
Forest land dominates 70 percent of the area, mostly in small holdings; residential uses increase concern over parcelization and fragmentation. About 15 percent of the area is in agricultural use and about 10 percent is urbanized.
Cultural Ecology
Many Native American tribes settled and hunted, fished, and farmed the land before European settlement in the early 1600s. Transportation and commerce are significant cultural influences. The Atlantic Ocean, rivers, and railroads provided early transportation routes. Fishing, whaling, shipbuilding industries, ironworks, tanneries, and textile mills decreased in importance following the 1800s. Metal-working and machining are important today. Sand, gravel, clay, granite, limestone,and marble are mined. Agriculture decreased as manufacturing increased. Historic and resource based tourism are important economic sectors.
Data Source: United States Department of Agriculture, Forest Service.
Compiled by Northeastern Forest Experiment Station, Northeastern Area State and Private Forestry, and the Eastern Region.
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