Natural Communities of NH -- Photo Guide


Sweet gale - alder shrub thicket  (S3)



Sweet gale - alder shrub thicket
communities form a narrow zone at the upland edge of pond shores in southern and central New Hampshire. They are temporarily flooded, and characterized by a diverse mixture of tall and medium shrubs, with lesser amounts of dwarf shrubs and herbs. The species composition is more diverse than highbush blueberry - winterberry shrub thickets.

Soils are variable, consisting of sand or sand and gravel, interbedded sand and peat turf, or sandy muck on open pond shore beach ridge or upland edge. They have shallow hemic O horizons (0-13 cm), variable A horizons (0-55 cm), with sand and gravel deposits to over 1 m. A single location included in this type has over 125 cm of peat at the surface.

Characteristic vegetation:
Diagnostic species occurring with high frequency and/or abundance (and that are absent or infrequent in dense highbush blueberry - winterberry shrub thickets) include sweet gale (Myrica gale), speckled alder (Alnus incana), smooth alder (A. serrulata), steeplebush (Spiraea tomentosa), royal fern (Osmunda regalis), witherod (Viburnum nudum), northern arrowwood (V. dentatum), and large cranberry (Vaccinium macrocarpon).

Other, less frequent species include switch-grass (Panicum virgatum), rough goldenrod (Solidago rugosa), sensitive fern (Onoclea sensibilis), small headed white aster (Symphyotrichum racemosum), small-tussock sedge (Carex stricta var. strictior), grass-leaved goldenrod (Euthamia graminifolia), and broom sedge (Carex scoparia). Some of these less frequent species are also found in adjacent (lower) zones occupied by twig-rush sandy turf pond shore.


A good example of this community occurs along the south shore of Ossipee Lake, at the Ossipee Lake Natural Area in Ossipee. 

Sweet gale - alder shrub thickets
 sometimes occur as part of a larger sandy pond shore system.


Sweet gale - alder shrub thicket at Ossipee Lake (photo by Ben Kimball for the NH Natural Heritage Bureau)
Sweet gale - alder shrub thicket at Ossipee Lake (photo by Ben Kimball)

 sweet gale - alder shrub thicket at Ossipee Lake (photo by Ben Kimball for the NH Natural Heritage Bureau)
Sweet gale - alder shrub thicket at Ossipee Lake (photo by Ben Kimball)


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