''Hippuris vulgaris'' (from Greek: ἵππος — ''horse'' and οὐρά — ''tail''), known as mare's-tail or common mare's-tail, is a common aquatic plant of

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and

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ranging from

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to the

Tibetan Plateau The Tibetan Plateau (, also known as the Qinghai–Tibet Plateau or the Qing–Zang Plateau () or as the Himalayan Plateau in India, is a vast elevated plateau located at the intersection of Central, South and East Asia covering most of the Ti ...

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. It prefers non-acidic waters.

Description

The common mare's tail is a creeping,

perennial A perennial plant or simply perennial is a plant that lives more than two years. The term ('' per-'' + '' -ennial'', "through the years") is often used to differentiate a plant from shorter-lived annuals and biennials. The term is also wide ...

herb In general use, herbs are a widely distributed and widespread group of plants, excluding vegetables and other plants consumed for macronutrients, with savory or aromatic properties that are used for flavoring and garnishing food, for medicinal ...

, found in shallow waters and mud flats. It roots underwater, but most of its

leaves A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...

are above the water surface. The leaves occur in

whorls A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral d ...

of 6–12; those above water are 0.5 to 2.5 cm long and up to 3 mm wide, whereas those under water are thinner and limper, and longer than those above water, especially in deeper

stream A stream is a continuous body of water, body of surface water Current (stream), flowing within the stream bed, bed and bank (geography), banks of a channel (geography), channel. Depending on its location or certain characteristics, a stream ...

s. The stems are solid and unbranched but often curve, and can be up to 60 cm long. In shallow water they project 20–30 cm out of the water. It grows from stout

rhizome In botany and dendrology, a rhizome (; , ) is a modified subterranean plant stem that sends out roots and shoots from its nodes. Rhizomes are also called creeping rootstalks or just rootstalks. Rhizomes develop from axillary buds and grow hori ...

s. The

flower A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...

s are inconspicuous, and not all plants produce them. Studies of ''H. vulgaris'' in the Tibetan Plateau have shown that it is a prolific

methane Methane ( , ) is a chemical compound with the chemical formula (one carbon atom bonded to four hydrogen atoms). It is a group-14 hydride, the simplest alkane, and the main constituent of natural gas. The relative abundance of methane on Eart ...

emitter.Hirota, H., Tang, Y., Hu Q. et al. (2004) Methane emissions from different vegetation zones in a Qinghai-Tibetan Plateau wetland. Soil Biology & Biogeochemistry, 36, 737-748 ''H. vulgaris's'' roots extend into the anoxic zone of wetland soils and create a conduit for methane produced in the anoxic zone to travel to the atmosphere.

Uses

It can also be a troublesome weed, obstructing the flow of water in rivers and ditches.

References

External links

Jepson Manual TreatmentUSDA Plants Profile
{{Taxonbar, from=Q33115 Plantaginaceae Freshwater plants Plants described in 1753 Taxa named by Carl Linnaeus