Yellow floating heart growing in the eastern United States.Yellow floating heart
(Nymphoides peltata) is an herbaceous, perennial, aquatic plant. It is emergent and bottom-rooted. It can form dense mats that inhibit water recreation and crowd out native aquatic plants. Yellow floating heart has been popular for cultivation in water gardens but a recently passed law in Minnesota has made it illegal to buy, sell, or possess. This is because it can cause problems and spreads easily through stem fragments or seeds.
- Description
Appearance
Yellow floating heart is an emergent, bottom-rooted aquatic plant. It has heart shaped and wavy-edged floating leaves and yellow flowers with five fringed petals that rise above the water’s surface. It can reproduce through both seeds and broken off stem fragments. It creates dense mats of floating leaves on the water’s surface.Leaves and Stem
Leaves are 3-12 cm in diameter, round to heart-shaped, which resemble water lilies, and are green to yellow-green with slightly wavy margins. The undersides of leaves are often purple.Yellow floating heart is a rooted, perennial species with long branched stolons (horizontal stems) that can be up to two meters long and lie just below the water surface. Multi-leaved "plantlets" are produced at the nodes along with roots.Flowers
It has two to five bright yellow, five-petaled flowers (2-4 cm in diameter) with shallowly fringed petals borne above the water surface. Plants flower between May and October depending on water temperature.Seeds
Each flower produces one beaked capsule (2.5 cm), dispersing few to many smooth, flat, shiny seeds with stiff hairs along the edges.Rhizomes and Roots
Adventitious roots (roots that come off the stem) on the lake’s bottom grow in short, thick clusters and originate from rhizomes (modified stems which grow partly or entirely below the sediment).Biology
Yellow floating heart is a perennial herb that grows in lakes, ponds, swamps and channels with slow-moving water. It can grow in water 0.5-4.0 m deep, and it tolerates anaerobic (low oxygen) environments. This species can also survive on mudflats. The growing season for this species is April through late October; leaves have a 23–43 day life span. It also overwinters as dormant rhizomes (underground stems).The small fruits contain hairy seeds that float in the water and can attach to animals. Research shows dispersal mechanisms may include transport by waterfowl as well as chain-like rafts of floating seed. This species can also reproduce vegetatively; plant fragments (from nodes and leaves) and rhizomes can develop into new plants.Origin and Spread
The species is native to Eastern Asia and the Mediterranean. The main pathway of introduction is trade. Yellow floating heart is a popular plant for cultivating in the water garden industry and has a high potential for escape as it can easily propagate through stem fragments or seeds. Refer to the EDDMapS for current distribution.Don’t be fooled by this look-alike
Yellow floating heart looks similar to some native, beneficial floating plants found in Minnesota lakes and rivers but can be distinguished based on its unique leaf structure, flowers and the shape of its seeds.- Yellow pond lily (native) – has larger leaves that grow to 30 cm or more and has yellow flowers in the shape of a ball with six or more petals.
- American Lotus (native) – has larger, ovular, smooth leaves that grow to 30 cm or more.
- American white waterlily (native) – has white flowers and leaves are circular.
- Regulatory Classification
- Yellow floating heart (Nymphoides peltata) is a prohibited invasive species in Minnesota, which means it is unlawful (a misdemeanor) to possess, import, purchase, transport or introduce this species except under a permit for disposal, control, research or education.
- Threat to Minnesota Waters
- Invasive species cause recreational, economic and ecological damage—changing how residents and visitors use and enjoy Minnesota waters.Yellow floating heart impacts:
- Dense mats at the water’s surface inhibit water recreationists.
- Overtakes habitat and outcompetes native aquatic plants, potentially lowering diversity.
- Provides unsuitable shelter, food, and nesting habitat for native animals.
- What you Should Do
- People spread yellow floating heart through the illegal release of aquarium or water garden plants into public waters and through movement of water-related equipment. This species can easily reproduce through the dispersal of seeds or plant fragments making the spread through ‘hitchhiking’ on water-related equipment common. Do not dispose of unwanted aquatic plants or animals in or near public waters. Yellow floating heart plants should be disposed of in the trash sealed in a plastic bag.While yellow floating heart was previously a regulated invasive species, as of February 20, 2024, it is now prohibited, meaning it is illegal to possess, import, purchase, transport or introduce this species except under a permit for disposal, control, research or education. Refer to control methods for management options.Whether or not a lake is listed as infested, Minnesota law requires water recreationists to:
- Clean watercraft of all aquatic plants and prohibited invasive species.
- Drain all water by removing drain plugs and keeping them out during transport.
- Dispose of unwanted bait in the trash.
- Dry docks, lifts, swim rafts and other equipment for at least 21 days before placing equipment into another water body.
Report new occurrences of yellow floating heart to the DNR immediately by contacting your DNR Invasive Species Specialist or log in and submit a report through EDDMapS. - Control Methods
- Management of invasive aquatic plants involving either mechanical removal of plants or application of herbicides to public waters requires a permit from the DNR. Talk to a DNR invasive species specialist for more information.Mechanical control can be done by cutting the plant below the water surface several times per summer and removing all cut parts from the water. However, this is labor intensive, and in some instances, cutting has facilitated spread of yellow floating heart. Hand digging or raking is best for small infestations, especially when water levels are low. Hand dig isolated plants with care, as root fragments can spread and sprout.Herbicide control can be done using a variety of herbicides labeled for use on floating leaf plants. An aquatic herbicide formulation is required if treatment is to be conducted on or near water.
- Resources
