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Ecological Communities

Mid-reach stream

The aquatic community of 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 linear
leaved pondweeds such as sago pondweed.

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 represent less than 50% cover but
include gray and silky dogwoods, arrowwood, raspberries, sumac, and
 eastern red cedar.

Successional shrubland

A woodland community that commonly occurs on abandoned agricultural
fields and pastures, particularly on fertile soils, on slopes along the
lakes, and occasionally on well drained soils of alluvial valleys. The
 dominant tree is usually red cedar. Gray birch, hawthorn, buckthorn,
 white ash, and black walnut are common associates. Shrubs and ground
 layers are similar to that of successional old field.

Successional forest

A forest 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. Tree seedling 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.

Shallow emergent marsh

A marsh that is better drained than a deep emergent marsh; water depths may range from 15 cm to 1 m 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, rice cutgrass, mannagrass, three-way sedge, bulrushes, sweetflag, wild iris, and water smartweed.

Shrub swamp

A shrub dominated wetland that occurs along a lake or river, in a wet depression , or as a transition between wetland and upland communities. The substrate is usually mineral soil or muck. Alder or willow are common dominants. Other characteristic species include red osier, silky, gray dogwoods, meadowsweet, steeplebush, swamp azalea, highbush blueberry, maleberry, spicebush, viburnums, and buttonbush.