Emergent marsh is dominated by robust emergent macrophytes, in pure stands of single species or in various mixtures. Dominants include cattails (Typha spp.), bulrushes (particularly Schoenoplectus acutus, S. tabernaemontani, and Bolboschoenus fluviatilis), bur-reeds (Sparganium spp.), giant reed (Phragmites australis), pickerel-weed (Pontederia cordata), water-plantains (Alisma spp.), arrowheads (Sagittaria spp.), the larger species of spike-rush (such as Eleocharis smallii), and wild rice (Zizania spp.). Emergent marsh can occur in a wide variety of hydrologic settings, including inland lake, Great Lakes, riverine and estuarine complexes.
Aquatic plants, including both emergent and submergent aquatic vegetation, form the foundation of healthy and flourishing aquatic ecosystems - both within lakes and rivers and on the shores and wetlands around them. They not only protect water quality, but they also produce life-giving oxygen. Aquatic plants are a lake's own filtering system, helping to clarify the water by absorbing nutrients like phosphorus and nitrogen that could stimulate algal blooms. Plant beds stabilize soft lake and river bottoms and reduce shoreline erosion by reducing the effect of waves and current.
Aquatic plants also serve as spawning habitat for fish and amphibians, as shelter for various life stages of a variety of species, and as nesting habitat for birds. Plant beds support populations of aquatic insects that serve as a food base for other species. Seeds and other plant parts provide vital nutrition to a number of waterfowl and other bird species. Healthy, native aquatic plant communities also help prevent the establishment of invasive exotic plants like Eurasian water-milfoil (Myriophyllum spicatum).
