Water Pennywort
Pennyworts, especially water pennywort, are commonly found in Maryland aquatic environments. Not as prevelant as marsh pennywort (H. umbellata), both pennyworts are succulent perennials that are members of the parsley family and native to America. Generally rooted in the mud along pond and ditch banks, they can form dense mats that float on the surface. These mats can actually break away from their roots and continue living and growing while free floating. The mats can also support other plants such as smart weeds, beggar-ticks, or alligator-weed. The mats may grow to such a density that they may impede waterflow in drainage canals and ditches, which can affect irrigation. Often, a variety of submersed aquatic plants may be found entangled among the roots. Many species of Hydrocotyle can grow well in either an aquatic or terrestrial habitat.