Potamogeton friesii | |
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Scientific classification | |
Kingdom: | Plantae |
Clade: | Tracheophytes |
Clade: | Angiosperms |
Clade: | Monocots |
Order: | Alismatales |
Family: | Potamogetonaceae |
Genus: | Potamogeton |
Species: | P. friesii |
Binomial name | |
Potamogeton friesii | |
Synonyms [2] | |
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Potamogeton friesii, known as flat-stalked pondweed, [3] or Fries' pondweed, [4] is an aquatic plant in the genus Potamogeton. It grows mainly in mesotrophic to eutrophic rivers, lakes, ponds and ditches, rarely in brackish water. It occurs in North America, Europe, western Asia and a few scattered locations elsewhere in Asia.
Flat-stalked pondweed grows annually from turions and seed, producing branching plants with slender, flattened stems that are well-branched. The submerged leaves are long, rather grass-like, sessile, and translucent. The leaf tips are mucronate (i.e. with the midrib extending out of the leaf, giving a pointed appearance). [5] Abundant turions are produced along the stem, especially in autumn as the plant disintegrates.
Flat-stalked pondweed could be confused with other fine-leaved pondweeds within its range, especially Potamogeton obtusifolius [5] but potentially also P. pusillus . The combination of open stipules, rounded tips to the leaves, dense flower spikes and a tendency to produce a mass of bushy growth at the surface all help to distinguish this plant, but use of a botanical key or flora is recommended.
Potamogeton friesii is diploid, with 2n=26. [6]
Two hybrids of Potamogeton friesii have been described, with P. crispus (P. × lintoniiFryer) and P. acutifolius (P. × pseudofriesiiDandy & G.Taylor). [7]
Flat-stalked pondweed was first described in 1847 by the Austrian botanist Franz Josef Ruprecht. [2] The specific name friesii commemorates the Swedish mycologist and botanist Elias Magnus Fries. [8] It is related to other fine-leaved pondweeds such as P. obtusifolius, P. foliosus and P. pusillus. [9]
Potamogeton friesii occurs predominantly in North America (Canada, northern USA), [10] Europe (Scandinavia, Germany, Poland, British Isles, NE and central France, Belarus, Ukraine, European Russia, Pyrenees, Carpathians), [8] There are isolated populations in southern Europe (Corsica, N Italy, Balkans) and in Asia (N China, Russia, Japan, Kazakhstan, Tajikistan). [8] [11]
In Britain, P. friesii occurs in a range of standing water habitats including ponds, ditches, canals, [12] sluggish rivers and shallow lakes, favouring calcareous waters. [13] [5] It is strictly a lowland plant [13] and is tolerant of eutrophication, especially in rivers. [14] [15] [16] Like other fine-leaved pondweeds, P. friesii probably benefits from a certain amount of disturbance to suppress competing vegetation.
Flat-stalked pondweed has suffered local declines and is thought to be extinct in the Czech Republic, [17] and is Endangered in Switzerland, [18] and Germany. [19] It is considered to have declined in Britain, but is still widespread, [13] and was listed as Near Threatened in 2002. [20] A more recent assessment for England only [21] reassessed its status as Vulnerable, reflecting ongoing population declines. However, in the Netherlands it is considered least concern. [22]
Flat-stalked pondweed is not presently in cultivation. Although its wide ecological tolerance suggests it may not be difficult to grow, it would probably require a deeper substrate than is usual in most ornamental ponds. It is also likely to compete poorly with other pond plants.
Potamogeton is a genus of aquatic, mostly freshwater, plants of the family Potamogetonaceae. Most are known by the common name pondweed, although many unrelated plants may be called pondweed, such as Canadian pondweed. The genus name means "river neighbor", originating from the Greek potamos (river) and geiton (neighbor).
Potamogeton crispus, the crisp-leaved pondweed, curly pondweed, curly-leaf pondweed or curled pondweed, is a species of aquatic plant (hydrophyte) native to Eurasia but an introduced species and often a noxious weed in North America.
Potamogeton perfoliatus is a perennial aquatic plant in the family Potamogetonaceae occurring in both standing and flowing freshwater habitats. It is widely distributed globally, occurring in all continents except South America and Antarctica.
Potamogeton praelongus, commonly known as whitestem pondweed in North America and long-stalked pondweed in Britain, is a large, perennial aquatic plant in the family Potamogetonaceae. It is widely distributed in lakes and rivers in the northern hemisphere, but is sensitive to poor water quality.
Potamogeton polygonifolius or bog pondweed is an aquatic plant. It is found in shallow, nutrient-poor, usually acid standing or running water, bogs, fens and occasionally ditches.
Potamogeton coloratus, the fen pondweed, is an aquatic plant in the genus Potamogeton. It is found in shallow peaty calcareous lakes, ponds and ditches, commonly associated with lowland fens.
Potamogeton lucens, or shining pondweed, is an aquatic perennial plant native to Eurasia and North Africa. It grows in relatively deep, still or slow-flowing, calcareous freshwater habitats.
Potamogeton alpinus is a species of perennial aquatic plant known by the common names alpine pondweed and red pondweed. It is widespread in the northern hemisphere in both rivers and lakes with good water quality.
Potamogeton diversifolius is a species of aquatic plant known by the common names waterthread pondweed and diverse-leaved pondweed. It is native to most of the United States, as well as sections of southwestern Canada, and northern Mexico, where it grows in water bodies such as ponds, lakes, ditches, and slow-moving streams. This is a perennial herb producing a very narrow, compressed stem branching to a maximum length around 35 centimeters. It has thin, pointed linear leaves a few centimeters long spirally arranged about the thin stem. The inflorescence is a small spike of flowers emerging from the water surface. Inflorescences also grow on submersed sections of the stem; these are smaller and spherical. It can be difficult to distinguish from similar species of pondweed.
Potamogeton epihydrus is a perennial aquatic plant known by the common names ribbonleaf pondweed and Nuttall's pondweed, and American pondweed in the United Kingdom. It is native to much of North America, where it grows in water bodies such as ponds, lakes, ditches, and slow-moving streams.
Potamogeton gramineus is a species of aquatic plant known by the common name various-leaved pondweed, variableleaf pondweed, grass-leaved pondweed or grassy pondweed, native to the northern hemisphere where it grows in shallow, clean water.
Potamogeton pusillus is a species of aquatic plant known by the common names small pondweed, lesser pondweed or least pondweed. It occurs in standing and slow-flowing freshwater habitats throughout the Northern Hemisphere.
Potamogeton compressus is a species of aquatic plant known by the common names grass-wrack pondweed, flatstem pondweed and eel-grass pondweed.
Potamogeton obtusifolius, known as blunt-leaved pondweed, is an aquatic plant in the genus Potamogeton. It grows mainly in mesotrophic to eutrophic lakes, ponds and ditches, rarely in brackish water. It occurs primarily in Central Europe, the British Isles, Fennoscandia and eastern North America.
Stuckenia is a genus of flowering aquatic plants. It contains approximately 30 species that grow in shallow water. Pondweed is a common name for plants in this genus.
Potamogeton berchtoldii, common name small pondweed, is an aquatic plant.
Potamogeton acutifolius is a European species of aquatic plant in the family Potamogetonaceae, known by the common name sharp-leaved pondweed. It is threatened and declining in at least part of its range.
Potamogeton × griffithii is a hybrid pondweed between Potamogeton alpinus and Potamogeton praelongus. It occurs in oligotrophic, moderate alkalinity lakes.
Potamogeton trichoides is a species of aquatic plant known by the common name hairlike pondweed, native to Europe and western Asia where it grows in calcareous, usually nutrient-rich standing or slow-flowing water.
Potamogeton × angustifolius is a hybrid pondweed between Potamogeton gramineus and Potamogeton lucens, known as long-leaved pondweed. It is widespread in rivers and lakes except where the water is very soft.