- Hydrocharis morsus-ranae is a free-floating aquatic plant that resembles a miniature water lily.
- The leaves of the plant are round, and heart shaped, (the size of a Canadian two-dollar coin) with veins coming off the mid-vein that arch broadly following the shape of the leaf. The undersides of the leaves are dark purplish-red and have a spongy coating, which helps the plant float on top of the water.
- It has a single white flower approximately 0.6 in. (1.5 cm) in diameter with three rounded petals and a yellow center.
- Seeds are approximately 0.04 in. (1 mm) long.
- Ecological Threat
- In the fall, Hydrocharis morsus-ranae breaks apart and decomposes, falling to the bottom of the lake. The decomposition of huge volumes of vegetation in the water can deplete dissolved oxygen levels. If there are insufficient amounts of oxygen, fish and other aquatic organisms can die. These thick mats can also impede the movement of large fish and diving ducks.
Leslie J. Mehrhoff
Leslie J. Mehrhoff
EDDMapS Distribution - This map is incomplete and is based only on current site and county level reports made by experts, herbaria, and literature. For more information, visit www.eddmaps.org
State Regulated List - This map identifies those states that list this species on their regulated list. For more information, visit Invasive.org
Invasive Listing Sources
- California Noxious Weeds
- EDDMapS Ontario
- Faith Campbell, 1998
- Idaho Noxious Weeds
- Maine Noxious Weeds
- New Hampshire Invasive Species Committee. 2005. Guide to Invasive Upland Plant Species in New Hampshire. New Hampshire Department of Agriculture, Markets and Food Plant Industry Division and New Hampshire Invasive Species Committee.
- New Hampshire Prohibited Aquatic Species
- Vermont Department of Environmental Conservation
- Vermont Noxious Weeds
- WeedUS - Database of Plants Invading Natural Areas in the United States
- Wisconsin's Invasive Species Identification, Classification and Control Rule