Natural Communities of NH -- Photo Guide

Highbush blueberry - mountain holly wooded fen  (S3S4)

Highbush blueberry - mountain holly wooded fen occurs mostly as a border thicket around more open dwarf heath peatlands in southern and central parts of the state. It is characterized by a mixture of tall and medium shrub species. Frequent species include highbush blueberry, mountain holly, leatherleaf, sheep laurel, and black huckleberry. Sphagnum moss is common, with moderately-developed hummock-hollow topography.

This is an oligotrophic to weakly minerotrophic community. Average pH is 3.9. The medium shrub layer averages ca. 0.85 m in height and is therefore taller than that of dwarf heath communities. Peat is moderately well decomposed within the upper 0.5 m, and hummock-hollow topography is moderately well developed (average hummock height 0.26 m).

Characteristic Vegetation: This community often has a sparse tree canopy of black spruce (Picea mariana), larch (Larix laricina), and sometimes white pine (Pinus strobus) or pitch pine (Pinus rigida). Tall shrubs average ca. 15% cover (range is 1-30%) and usually include highbush blueberry (Vaccinium corymbosum), mountain holly (Nemopanthus mucronatus), male berry (Lyonia ligustrina), and black chokeberry (Photinia melanocarpa). Dwarf and medium-height shrubs are on average more abundant (34% cover) than tall shrubs and include leatherleaf (Chamaedaphne calyculata), sheep laurel (Kalmia angustifolia), black huckleberry (Gaylussacia baccata), and occasionally bog laurel (Kalmia polifolia). Virginia chain fern (Woodwardia virginica) and Billing's sedge (Carex trisperma var. billingsii) are occasional. Sphagnum magellanicum is dominant, while S. rubellum is characteristic but less frequent and abundant than in Sphagnum rubellum - small cranberry dwarf heath moss carpets that lack tall shrubs. Sphagnum bartlettianum, a species with coastal and southern distributional tendencies, occurs in some examples. Winterberry (Ilex verticillata) and forbs indicative of more minerotrophic conditions are generally not present.

Variants: Two variants are apparent (though they are quite similar, both environmentally and structurally):

1. Rhodora - mountain holly - Sphagnum russowii variant
   This variant is characterized by a very high frequency and abundance of rhodora (Rhododendron canadense) and Sphagnum russowii with little or no highbush blueberry (Vaccinium corymbosum). The most frequent tall shrub species are mountain holly (Nemopanthus mucronatus) and witherod (Viburnum nudum var. cassinoides). Peat is moderately well decomposed within 0.25 m of the surface. Other hummock Sphagnum mosses include S. capillifolium and S. fuscum. Sphagnum russowii is occasional but more frequent than in the next variant, and S. angustifolium is occasional to sometimes abundant.

2. Highbush blueberry - huckleberry - large cranberry variant
   This variant has a high frequency and abundance of highbush blueberry (Vaccinium corymbosum) and black huckleberry (Gaylussacia baccata), and large cranberry (Vaccinium macrocarpon) occurs in low abundance. rhodora (Rhododendron canadense) and mountain holly (Nemopanthus mucronatus) are occasional but not as frequent as in the other variant. There is also a higher frequency of dwarfed black spruce (<1.5 m). Peat is poorly decomposed to a greater depth (0.7 m).

Good examples of this community occur in the Ossipee Lake Natural Area (south of Ossipee Lake) (Ossipee), east of Pine River (Effingham), northwest of Umbagog Lake (Errol), Spruce Swamp (Fremont), and Big Church Pond (Albany).

Highbush blueberry - mountain holly wooded fens sometimes occur as part of larger poor level fen/bog systems, kettle hole bog systems, coastal conifer peat swamp systems, and temperate peat swamp systems.

Highbush blueberry - mountain holly wooded fen at Watts Sanctuary (photo by Dan Sperduto)
Highbush blueberry - mountain holly wooded fen
at Watts Sanctuary (photo by Dan Sperduto)

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