Yellow floating heart (Nymphoides peltata)
Yellow Floatingheart is an aquatic, bottom rooted perennial plant that is native to Eurasia and the Mediterranean Sea region1. It was popular as an ornamental plant for water gardens in North America, but has escaped from cultivation and become invasive in Canada and the US. Yellow Floatingheart is currently found in isolated patches within the Credit River Watershed.
Yellow Floatingheart grows from a rhizome anchored in the soil, and prefers to grow in slow moving waters such as lakes, rivers, ponds, and marshes. It typically grows in water between 0.5 and 4 m deep, but can also survive in wet mud. Its heart shaped leaves are usually opposite and unequal, measuring 3 – 10 cm across1. The leaves float at the water surface and have wavy, slightly scalloped edges and a pink or purple tinge on their undersides. Yellow Floatingheart produces bright yellow flowers that are held above the water by a single long stalk. Each flower has five petals arranged like the spokes of a wheel. Yellow Floatingheart is known for its long blooming period which lasts from July to September. The seeds produced are contained in beaked capsules. The seeds are flat, oval, about 3.5 mm long, and are capable of floating with the aid of hairs on their edges1. The hairs allow the seeds to attach to waterfowl and other animals, which then in their dispersion. Yellow Floatingheart can also reproduce vegetatively by fragmentation.
Yellow Floatingheart is commonly sold as a pond plant at nurseries. However, it can then escape from water gardens, into natural waterways either through flooding or attaching its seeds to waterfowl and other animals. In aquatic ecosystems, it can form dense mats of vegetation that shade or crowd out native aquatic plants. In extremely dense stands, it can cause the water to become stagnant, resulting in lower dissolved oxygen levels, which harm fish and other aquatic organisms2.
The best way to stop the spread of Yellow Floatingheart is to not plant it in the first place, especially in areas that may be flooded or in areas that are connected to natural water courses. Consider using native aquatic plants for water gardens instead. In established populations, control is very difficult. However, manual removal such as cutting and harvesting can be done to stop the plant from spreading further. Barrier material can also be used in some situations to suppress growth of Yellow Floatingheart; however fluctuating water levels make this technique difficult to implement and be effective.
For more information on how to control Yellow Floatingheart, please contact CVC via email or to report sightings of Yellow Floweringheart call the Ontario Federation for Anglers and Hunters Invasive Species Hotline at 1-800-563-7711 and add the sighting to the EDDMaps Ontario website.
https://www.youtube.com/watch?v=w3VPdqWtX6U (Video created by Michigan Department of Environmental Quality)
- Indiana Department of Natural Resources. 2005. “Aquatic Invasive Species: Yellow Floating Heart”. Web. 21 August 2018. https://www.in.gov/dnr/files/YELLOW_FLOATING_HEART.pdf
- Ontario’s Invading Species Awareness Program. 2006. “Yellow Floating Heart: Invades Ontario Waters”. Ontario Federation of Anglers and Hunters. Web. 21 August 2018. http://londonregionreel.pbworks.com/f/YellowFloatingHeart.pdf