Buttonbush shrubland (S4)
(a combination of the former oxbow buttonbush swamp and buttonbush basin swamp communities)
Buttonbush shrublands form in small basins and oxbow ponds where standing water is present for most or all of the growing season. The persistence of standing water throughout the growing season limits shrub and herb diversity. Buttonbush (Cephalanthus occidentalis), perhaps the most flood-tolerant deciduous shrub in
This community is most abundant in central and southern parts of the state. It can occur in basins on glacial till are characterized by well-decomposed organic soils, perched water tables, and seasonally to semi-permanently flooded hydrology. However, some examples occur on alluvial soils in oxbow depressions that are periodically inundated by riverbank overflow. While this community is usually flooded, exposed soil is periodically required for buttonbush regeneration. This species can also be found with other shrubs and herbs along lake and pond margins and slow-moving streams.
Characteristic vegetation: Buttonbush typically dominates with a moderate to dense cover. Other characteristic species include red maple (Acer rubrum), American elm (Ulmus americana), highbush blueberry (Vaccinium corymbosum), speckled alder (Alnus incana ssp. rugosa), winterberry (Ilex verticillata), swamp rose (Rosa palustris), leatherleaf (Chamaedaphne calyculata), sheep laurel (Kalmia angustifolia), northern arrowwood (Viburnum dentatum var. lucidum), marsh fern (Thelypteris palustris var. pubescens), royal fern (Osmunda regalis var. spectabilis), cinnamon fern (Osmunda cinnamomea), common water horehound (Lycopus uniflorus), and swamp candles (Lysimachia terrestris). Many of the shrubs mentioned above may occur with greater cover on drier basin margins or other relatively higher ground in the wetland. Pioneer mosses often grow on the stems of buttonbush near the water line.
Good examples can be seen at
buttonbush shrubland community in an oxbow of the Blackwater River (photo by Ben Kimball)
buttonbush shrubland in a basin at Stratham Hill Park in the Seacoast region (photo by Ben Kimball)
buttonbush shrubland in a small basin on Beaver Brook Association land in Hollis (photo by Ben Kimball)