View source for Equisetaceae

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| name = ''Equisetaceae''
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| color = IndianRed
| image = Upload.png   <!--- Freesia.jpg -->
| image_width = 240px    <!--- leave as 240px if horizontal orientation photo, or change to 180px if vertical -->
| image_caption =     <!--- eg. Cultivated freesias -->
| regnum = Plantae
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| familia = Equisetaceae
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{{Inc|
Equisetaceae (from the genus Equisetum, meaning horse-bristle). Horse-tail Family. Fig. 1. Plants of striking appearance, often with rhizomes and with a straight, aerial, striated axis bearing whorls of connate, scale-like leaves at the nodes: from the nodes also frequently arise slender branches of different structure which bear different but still scale-like leaves: the stem is hollow, and besides the central canal often contains numerous additional large canals imbedded in the outer tissue: spores of one kind (not microspores and macrospores): sporangia 5-9, borne on the under surface of peltate, polygonal scales which form a terminal cone; dehiscence longitudinal; spores green, provided with several hygroscopic "elaters” which aid in dissemination: prothallia green, unisexual, the female largest, branched.

A single genus and about 24 species are known, of which one section is tropical, the other of temperate distribution. Ten species are native in the eastern United States. The family is very distinct and shows no definite relationship to any existing plants. The habit, the undifferentiated spores, the peltate sporophylls, and the dioecious emergent prothallia are distinctive. The arrangement of the canals and also of the stomates along the stem are important in the distinction of species.

The stems of E. hiemale, rich in silica, were formerly much used for scouring and for polishing woods, and are still used to some extent. E. arvense and E. sylvaticum have been used for polishing tin vessels, hence the name "tinweed." Several species have been used in medicine, as diuretics, E. giganteum is employed as an astringent. E, arvense and E. palustre are bad weeds in parts of Europe.

Several species have been advertised by American dealers in native plants.{{SCH}}
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