Physiognomy and Structure: This group usually has a moderate to dense cover of graminoids and forbs 0.5-1.5 m tall. Shrubs and trees are usually absent to uncommon (<25%) but stands in the Allegheny Mountains of West Virginia can have a dense layer of shrubs approximately 2 m tall.

Floristics: A variety of forbs and graminoids can dominate stands of this group. Graminoids may be more common across the group and some can be very abundant, forming low-diversity stands strongly dominated by a few species but stands with a wide variety of forbs and graminoids can also be found. Graminoids that can be common to dominant are Calamagrostis canadensis and Carex spp., usually Carex lacustris, Carex stricta, Carex vesicaria, and Carex utriculata, Glyceria striata, Leersia oryzoides, Scirpus atrovirens, and Scirpus cyperinus. Forbs that may be common or dominant include Boltonia asteroides var. asteroides, Eutrochium fistulosum (= Eupatorium fistulosum), Eupatorium perfoliatum, Impatiens capensis, Impatiens pallida, Mentha arvensis, Sagittaria latifolia, Solidago canadensis, Solidago rugosa, Symphyotrichum racemosum, and Verbesina alternifolia. A variety of other graminoids and forbs may be present, including Agrostis gigantea, Carex aquatilis, Dulichium arundinaceum, Glyceria grandis, Juncus effusus, Poa palustris, and Typha spp., and common forbs include Acorus calamus, Boehmeria cylindrica, Comarum palustre, Iris versicolor, Polygonum amphibium, Symphyotrichum lanceolatum, and Thelypteris palustris. Shrubs typically have <25% cover and include Alnus incana, Alnus serrulata, Cephalanthus occidentalis (in the east), and Vaccinium corymbosum. Some stands noted in West Virginia have a high cover of Spiraea alba. Trees are absent to uncommon and may include Acer rubrum, Fraxinus nigra, Fraxinus pennsylvanica, Salix nigra, Thuja occidentalis, and others. The grass Phalaris arundinacea and the exotic shrubs Rhamnus cathartica and Rosa multiflora are sometimes invasive in this community and can become very abundant.

Dynamics:  Stands are flooded or saturated for at least a few weeks each year and can remain saturated for most of the growing season in some stands. Prolonged changes in hydrologic regime, either wetter or drier, often result in a change to a different group. This group is common behind beaver dams.