Montane black spruce - red spruce forest (S1)
Montane black spruce - red spruce forest is an uncommon to rare community type in New Hampshire. It is characterized by black and red spruce on poorly to moderately well drained soils. It occurs in the White Mountains and the North Country around heathlands and sloping and level fens in mid- to high-elevation valley bottoms beginning at 2,000–3,000 ft. elevation. Shrub, herb, and bryophyte species compositions resemble those of other spruce - fir forests (e.g. lowland spruce - fir forest). Compared to black spruce swamps, this community occurs on mineral soil, and has a lower abundance of heaths and a broader diversity of shrubs and conifers.
Known examples from the upper Pemigewasset River valley occur on mineral soils with a significant silt component and a moderately shallow organic layer. The silt impedes drainage, contributing to an increase in soil moisture. The mid- to high-elevation valley positions also trap cold sinking air, indirectly contributing to the nutrient-poor conditions. These are cryic soils (the coldest soil temperature regime in the state). Examples in the North Country occur on firm, gravelly silt loams overlain by a thin organic layer.
Characteristic vegetation: Black spruce (Picea mariana) and red spruce (Picea rubens) are the dominant trees. They can occur in various amounts relative to each other. Balsam fir (Abies balsamea) is less abundant or locally absent. Characteristic shrub and herb species common to other spruce - fir communities include cinnamon fern (Osmunda cinnamomea), interrupted fern (O. claytoniana), sheep laurel (Kalmia angustifolia), Labrador-tea (Ledum groenlandicum), creeping snowberry (Gaultheria hispidula), bunchberry (Cornus canadensis), Bartram’s serviceberry (Amelanchier bartramiana), and various bryophytes.
A good example of this community occurs in the vicinity of Ethan and Shoal Ponds in the White Mountains (Livermore).
Montane black spruce - red spruce forest may occur as part of a larger lowland spruce - fir forest/swamp system.