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Ecological Communities

Appalachian oak-hickory forest

A hardwood forest with more than 60% canopy cover of trees that occurs on well-drained sites, usually on flat hilltops, upper slopes, or south and west facing slopes. Dominant trees include one or more of red oak, white oak, and black oak. Mixed with oaks, are one or more of pignut, shagbark, and sweet pignut hickory. Common associates are white ash, red maple, and hop hornbeam. Small trees include flowering dogwood, witch hazel, shadbush, and choke cherry. Shrubs and groundlayer flora are diverse. Shrubs include maple-leaved viburnum, blueberries, red raspberry, gray dogwood, and beaked hazelnut.

Floodplain forest

A hardwood forest found on alluvial gravels on low terraces of floodplains of larger creeks and creek deltas. Characteristic trees include sycamore, cottonwood, box elder, silver and red maple, butternut, crack and white willow. American elm was once present. Characteristic vines and shrubs are Virginia creeper, poison ivy, and spicebush. Characteristic herbs are white snake root, green dragon, jewelweed, ostrich fern, and jumpseed.

Midreach stream

The aquatic community of a stream that has a well-defined pattern of alternating pool, riffle, and run sections. Waterfalls and springs may be present. Typical aquatic macrophytes include waterweed and pondweeds. Persistent emergent vegetation is lacking.

Riverside sand/gravel bar

A meadow community that occurs on sand and gravel bars deposited within, or adjacent to, a river channel. The community may be very sparsely vegetated, depending on the rates of deposition and erosion of the sand or gravel. Characteristic species include sandbar willow (Salix exigua), sand-cherry (Prunus pumila), dogbane (Apocynum cannabinum), switchgrass (Panicum virgatum), and poison ivy (Toxicodendron radicans).

Rocky headwater stream

The aquatic community of a small to moderate sized rocky stream with a moderate to steep gradient that lacks persistent emergent vegetation. The cold water stream flows over eroded bedrock near the stream origin and contains alternating riffle and pool sections. These streams typically have mosses and algae present, but few larger rooted plants.

Sedge meadow

A wet meadow with permanently saturated and seasonally flooded organic soils in wetlands that receive mineral nutrients via groundwater or streams. There is usually little peat accumulation and floating mats are not formed. Sedge meadows typically occur along streams and near the inlet and outlets of lakes and ponds. The dominant species is a tussock-sedge, Carex stricta, usually with about 50% cover. Other characteristic herbs include sedges (C. lacustris and C. rostrata), bluejoint grass, sweetflag, joe-pye weed, tall meadow rue, and bulrushes.

Shale cliff and talus community

A community with sparse vegetation that occurs on nearly vertical exposures of shale bedrock, ledges, and talus. The talus is unstable, there is little soil. Characteristic species include blunt-lobed woodsia, rusty woodsia, hairy penstemon, herb-Robert, panic grass, Carex pensylvanica, and eastern red cedar.

Shallow emergent marsh

A shallow marsh is better drained than a deep emergent marsh; water depths may range from 15cm to 1m during flood stages, but the water level usually drops by mid- to late-summer and the substrate is exposed. Characteristic plants include bluejoint grass, reed canary grass, cutgrass, manna grass, spikerushes, bulrushes, sweetflag, wild iris, and water smartweed. Marsh communities occur on mineral soils or fine-grained organic soils that are permanently saturated. They are often found near the Finger Lakes or in wetlands near a drainage divide. Because water levels may fluctuate, exposing substrate and aerating the soil, there is little or no accumulation of peat.

Successional northern hardwoods

A forest with more than 60% canopy cover of trees that occurs on sites that have been cleared or otherwise disturbed. Dominant trees are usually two or more of the following: red maple, white pine, white ash, gray birch, quaking aspen, big-tooth aspen, and, less frequently, sugar maple and white ash. Tree seedlings and saplings may be of more shade tolerant species. Shrubs and ground cover species may be those of old-fields. In abandoned pasturelands apples and hawthorns may be present in the understory.

Successional old field

A meadow on sites cleared, plowed, and then abandoned. The ragweed type occurs on fields 1 to 3 years after last cultivation; ragweed, daisy, Queen Anne's lace, crab grass, golden foxtail, and chickweed are common. The goldenrod subtype occurs 3 - 15 years after last cultivation. Dominant species are perennial composites: goldenrods and asters. Other herbs include timothy, orchard grass, smooth brome, bluegrasses, quackgrass, sweet vernal grass, evening primrose, old-field cinquefoil, wild strawberry, and hawkweeds. Shrubs and trees represent less than 50% cover but include gray dogwood, arrowwood, raspberries, blackberries, sumac, red maple and white pine.

Successional shrubland

A shrubland with at least 50% cover of shrubs that occurs on agricultural fields 10 - 25 years after abandonment, following other disturbance, and especially on sites with restricted drainage. Characteristic shrubs include gray dogwood, raspberries, hawthorn, serviceberries, chokecherry, sumac, nannyberry, arrowwood and buckthorn. Herbs are those of old-fields. Seedlings of white pine, red maple and white ash are usually present.