Oxbow NWR Final CCP - U.S. Fish and Wildlife Service

Vernal Pool: Photo by Rob Vincent
Wet Meadow
Chapter 3: Refuge and Resource Descriptions
Seven of the 15 ponds supported wet meadow communities. The wet
meadow communities have many grass and forb plant species that vary
widely between ponds and within meadows on a single pond. The most
frequently occurring species in the wet meadow are cutgrass (Leerzia
oryzoides), swampcandle (Lysimachea terrestris), common arrowhead
(Sagittaria latifolia), false nettle (Boehmeria cylindrica), and needle rush
(Eleocharis acicularis).
Deep Marsh
Deep marsh communities occur either as a band between meadow
communities and open water, or covering large areas on shallow ponds.
Deep marsh is characterized by emergent species along with floating
leaved and submersed species. Pickerelweed (Pontederia cordata) is the
most characteristic species, forming dense floating mats over large
expanses on many of the ponds.
Open Water Aquatic
There are three aquatic cover types which are delineated by water depth.
Shallow water areas are characterized by a dense cover of coontail
(Ceratophyllum demersum), followed by a zone lacking emergent species
with a small amount of watermeal (Wolffia spp.), and a second variety of
coontail (Ceratophyllum echinatum). The deepest aquatic cover type is
distinguished by a high frequency of pondweed (Potemogeton pusillus) and
yellow water lily (Nuphar variegatum) (Hickler 1995).
A general description of the types of oxbow pond communities (with a
cross-reference to the most similar NVCS designation) is provided in Table
3-2.
Table 3-2: Oxbow Pond Vegetation Communities
Type of Oxbow Community NVCS Cross-reference
Buttonbush Swamp Palustrine Cephalanthus occidentalis shrub thickets
Wet Meadow Palustrine medium tall graminoid vegetation
Deep Marsh Mixed marsh emergents community type: RI
Lacustrine emergent community:ME
Vernal Pools
Vernal pools are a priority habitat type within the State of
Massachusetts. Many vernal pools have been identified on Oxbow
NWR, associated with the river floodplain and the adjacent forested
wetlands. Vernal pools are temporary freshwater depressions which
hold spring rains and snow-melt waters, and then typically dry out
Comprehensive Conservation Plan
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