Yellow Floating Heart

The showy 5-petalled flower of the yellow floating heart.

Habitat: Yellow floating heart is found within the floating-leaf plant community. It can grow in various substrates (sand, mud, gravel, etc.), in littoral areas from water’s edge to a depth of 4m. 

Description: Rounded to heart-shaped floating leaves (3-10 cm in diameter) emerge on long stalks from rooted stems. Each rooted stem supports a loosely branched group of several stems. The leaves are typically wavy (shallowly scalloped) along the outer edges and have purplish undersides. The flowers are showy (3-4 cm in diameter), bright yellow with five distinctly fringed petals. They are held above the water surface on slender stalks with 1 to 5 flowers per stalk. The fruit capsule is 2.5 cm long and contains numerous seeds. The seeds are oval and flat (about 3.5 mm long) and hairy along their outer edges.

Origin and Range: Yellow floating heart is native to parts of Europe and Asia. It was introduced to this continent as an ornamental pond species. It has not yet been found in New Brunswick. However, in Canada, it can be found in Nova Scotia, Quebec, Ontario, Newfoundland, and British Columbia and can be found in every New England state in the U.S except Maine.

Annual Cycle: Yellow floating heart is an aquatic perennial that propagates by seeds, fragmentation, and spreading rhizomes. Many floating- leaved plants lack the ability to propagate by fragmentation, but in the case of yellow floating heart, broken leaves with attached stem parts will form new plants. Viable seeds are produced abundantly and germinate readily. Seed hairs help the seeds float and aid their attachment to waterfowl, increasing possibility of spread to new areas.

Look Alikes: It may be confused with: fragrant waterlily (Nymphaea odorata), which have a white flower; spatterdock (Nuphar variegata) which have a ball-shaped yellow flower. It is most similar to the native little floating heart (Nymphoides cordata) which is nonetheless easily distinguished by its small white flowers.

Impact: Yellow floating heart can form dense mats of floating vegetation that excludes native species. It can also create stagnant areas
which results in a lower level of oxygen and negatively affects native fish habitat. The quality of native freshwater habitat suffers, and even recreational activities (like swimming and canoeing) can become difficult or impossible. Upon decaying, the increased biomass created by dense populations can, in some situations, lead to the eutrophication of water bodies.

 

 Each rooted stem supports a loosely branched group of several stems. All other heart-shaped floating leaved plants in New Brunswick only have one leaf per rooted stem. 

Each rooted stem supports a loosely branched group of several stems. All other heart-shaped floating leaved plants in New Brunswick only have one leaf per rooted stem. 

 Yellow floating heart can form dense mats that exclude native species. 

Yellow floating heart can form dense mats that exclude native species.