At least 15 species of Hydrocotyle occur in the United States and Hawaii, all very similar in appearance and habits. Most are native plants that occur primarily in warmer, more tropical climates.
These are perennial plants that reproduce from seeds and spread rapidly by their rhizomes. Some larger-leaved varieties are aquatic and occur along marshes or pond margins, and all species favor a habitat with excessive moisture. Some are a serious turf pest.
Pennywort, or Dollarweed, is easily identified by its thick, shiny, round leaves which attach to their stalk at the center of the leaf, creating an “umbrella” shape. The stalk is very long and upright, and leaves have distinctly scalloped margins. The flowers occur in clusters at the ends of stalks that place them just above the leaves, and each flower is very small, white, and inconspicuous.
Characteristicts Important to Control:
When it occurs in turf a systemic broadleaf herbicide will be effective. Reduction of moisture where possible will reduce the ability for these plants to spread.