Coefficient of Conservatism:
Coefficient of Wetness:
Sandy, boggy, or marshy shores, sometimes in shallow water; sphagnum bogs, where the rhizomes are an important component of floating mats; ponds and interdunal swales, fens; often in marly places.
The achenes are very distinctive; they are somewhat acorn-shaped at maturity, squarely truncate and often a little flaring at the base. Occasionally, the spongy basal tissue that “fills out” the achene to give it the acorn shape does not develop, leaving the achenes broadly ellipsoid.