Mixed tall graminoid - scrub-shrub marsh (S4S5)
Mixed tall graminoid - scrub-shrub marsh is a common meadow marsh type, often referred to as a “scrub-shrub” wetland. It occurs along stream drainageways and in open basins. It is transitional in structure, hydrology, composition, and location between shrub thicket and herb-dominated meadow marsh communities, and is often transitional to streamside fens, swamps, or shrub thickets. It is similar to tall graminoid meadow marsh, but contains a greater percentage of medium- and tall-height shrubs (up to 60% cover overall). The substrate consists of a thin, well-decomposed organic layer over fine mineral soils or fine mineral soils with a high organic content.
Characteristic Vegetation: Species include a mixture of tall graminoids such as bluejoint (Calamagrostis canadensis) and tussock sedge (Carex stricta), other tall grasses and sedges, cinnamon fern (Osmunda cinnamomea), royal fern (O. regalis), meadowsweet (Spiraea alba), and sweet gale (Myrica gale). Shrubs include highbush blueberry (Vaccinium corymbosum), winterberry (Ilex verticillata), speckled alder (Alnus incana), witherod (Viburnum nudum), and willows (Salix spp.). Sphagnum moss is infrequent.
This community is transitional to streamside poor fens that have a greater abundance of Sphagnum moss, Chamaedaphne calyculata (leatherleaf), sweet gale, and “peatland” sedges such as Carex utriculata (bottle-shaped sedge) and C. lasiocarpa (wire sedge).
Good examples occur at
Mixed tall graminoid - scrub-shrub marsh often occurs as part of a larger emergent marsh - shrub swamp system.
Scrub-shrub marsh along Follett's Brook in Durham (photo by Bill Nichols)
Mixed tall graminoid - scrub-shrub marsh along Heath Brook in Sandwich
(photo by Ben Kimball)