water fringe (Invasive Plants of Maryland)

water fringe

Nymphoides peltata

Description ⁷

Rhizomes horizontal. Stem cylindric, unbranched, sometimes producing rootlets from nodes. Leaves alternate at stem base but opposite at apex; petiole cylindric, 5-10 cm, base widened into an amplexicaul sheath; leaf blade ovate-orbicular to orbicular, 1.5-8 cm in diam., subcoriaceous, abaxially purple-brown and densely glandular, adaxially glabrous, base cordate, margin entire, veins indistinct. Flowers usually densely clustered at nodes, 5-merous, distylous. Pedicel 3-7 cm. Calyx 7-9 mm, lobed to near base; lobes elliptic-lanceolate to elliptic, apex obtuse. Corolla golden yellow, 2.5-3 cm, rotate, lobed to near base; lobes obovate, margin broadly membranous and irregularly laciniate, apex rounded to emarginate. Filaments sparsely pilose. Short styled flowers: ovary 5-7 mm; style 1-2 mm; stigma small, filaments 3-4 mm; anthers curved, sagittate, 4-6 mm. Long styled flowers: ovary 0.7-1.7 cm; style to 1 cm; stigma large, 2lobed, suborbicular; filaments 1-2 mm; anthers 2-3.5 mm. Glands golden yellow. Capsules elliptic, 1.7-2.5 × 0.8-1.1 cm. Seeds brown, compressed, elliptic, 4-5 mm, densely ciliate. Fl. and fr. Apr-Oct. 2n = 54.

As an invasive species ⁸

N. peltata are commonly sold for use in ornamental water gardens. The species is intentionally or accidentally transferred to lakes and rivers outside of its native range. In the United States, the first recorded occurrence of the plant was in 1882 in Massachusetts, and the plant has been sold domestically since the 1930s. N. peltata has been recorded in 29 U.S. states and Washington, D.C., and it has naturalized in slow-moving waters. In Canada, N. peltata has been found in Newfoundland, Nova Scotia, Quebec, Ontario, and British Columbia, but has not yet been naturalized. N. peltata was intentionally introduced to Sweden in the early 19th century and was first recorded as a non-indigenous species in 1870.[2] Native to central and eastern Britain, N. peltata was transported around Britain and Ireland as an ornamental plant and first documented in Ireland in before 1866. In 1988, N. peltata was discovered in New Zealand, where it is considered a noxious weed. It is also designated an invasive species in Sweden, Ireland, and parts of North America.

However, while N. peltata is an invasive species outside its native range, in its indigenous to Japan where it is now classified as a vulnerable species. In Spain, Belarus, and the Czech Republic, N. peltata is critically endangered, and it is endangered in Lithuania, and vulnerable in Germany and Switzerland.

N. peltata can have many negative ecological and social impacts on its introduced regions. N. peltata can rapidly grow and spread to form dense patches of vegetation on the water’s surface that restrict the amount of light penetrating the surface. As a result, native submerged macrophytes are excluded and biodiversity is reduced. Especially if algae are shaded out, entire food webs can be disrupted by dense populations of N. peltata. Dense N. peltata mats can also reduce the amount of oxygen in water and create stagnant water areas. Fish and other aquatic wildlife can also be forced to relocate once N. peltata mats form. N. peltata also affects internal fertilization patterns as it moves nitrogen and phosphorus up from the sediment to its floating biomass as it grows and releases these nutrients back into the ecosystem during its winter decomposition.

Socially, N. peltata can negatively impact recreational activities such as boating, fishing, and swimming. The presence of mats of N. peltata can also decrease the aesthetic value of waterbodies which can, in turn, depreciate property and tourism values.

Description ⁸

N. peltata is an aquatic bottom-rooted perennial species with underwater creeping stolons that extend up to 2 meters. Each node on a stolon can produce a new shoot and roots. N. peltata has cordate floating leaves that are 3-15 cm in diameter, green to yellow-green in color, have purple-tinted undersides, and are attach to submerged rhizomes. The leaves have slightly wavy margins and support a lax, or loose, inflorescence of two to five yellow, five-petal flowers (2-4 cm in diameter) with fringed petal margins. N. peltatapeduncles can rise several inches out of the water. Each flower produces a 1.5-2.5 cm beaked capsule which hold many flattened seeds with stiff marginal hairs.

N. peltata is similar in appearance to Nuphar variegata and species in the genus Nymphaea. N. variegata can be distinguished from N. peltata most easily by its larger leaves, which can measure up to 30 cm, and its cup-shaped flower. Nymphaea have angled leaf bases as opposed to the rounded leaf bases of Nymphoides, and Nymphoides have significantly longer peduncles that support smaller flowers. In order to identify different species within Nymphoides, flowers are usually required.

Range description ⁹

N. peltata is native to Europe and northern Asia, from the Baltic States south to the Iberian Peninsula and east through the Middle East, the Caucasus, Jammu and Kashmir in India, Siberia and Mongolia to the Russian Far East, China, Japan and Korean Peninsula. It is naturalised in North America.

Sources and Credits

(c) Margrit, some rights reserved (CC BY-NC-SA), http://www.flickr.com/photos/27126314@N03/4936511265/
(c) Xth-Floor, some rights reserved (CC BY-SA), https://upload.wikimedia.org/wikipedia/commons/f/fe/Vrbensk%C3%A9_rybn%C3%ADky_-_%C5%A0nejdl%C3%ADk_-_Nymphoides_peltata.jpg
(c) licensed media from BioImages DwCA without owner, some rights reserved (CC BY-NC-SA), http://www.bioimages.org.uk/html/../image.php?id=108853
(c) Michael Wunderli, some rights reserved (CC BY), https://farm1.staticflickr.com/345/19107458680_38690e4047_o.jpg
(c) Howard, R.A., some rights reserved (CC BY-NC-SA), https://collections.nmnh.si.edu/services/media.php?env=botany&irn=10366494
(c) James Bailey, some rights reserved (CC BY-NC), uploaded by James Bailey
(c) Missouri Botanical Garden, 4344 Shaw Boulevard, St. Louis, MO, 63110 USA, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/5001568
(c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Nymphoides_peltata
(c) International Union for Conservation of Nature and Natural Resources, some rights reserved (CC BY-NC-SA), http://eol.org/data_objects/34605336

More Info

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water fringe

Description 7

As an invasive species 8

Description 8

Range description 9