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Scouring Rush

Equisetum hyemale affine Horsetail family (Equisetaceae)


Scouring Rush (Equisetum hyemale affine) is not a rush, but a horsetail. The horsetails are closely related to ferns and both were common during the Carboniferous period (280-345 million years ago), when tree-sized horsetails and ferns occurred. This perennial plant is 2-5' tall, producing both fertile and infertile shoots. Each shoot has a single central stem that is jointed, unbranched, more or less erect, and ¼–¾" (6-18 mm.) across. The central stem is medium green, olive-green, or dark green, rough in texture, and evergreen. The individual joints that make up the central stem are up to several inches long; the upper joints are usually shorter than the lower joints. The stem joints have about 15-40 fine longitudinal ridges. At the conjunctions of adjacent joints, there are appressed ring-like sheaths up to ¾" long. Except along their upper and lower rims, the sheaths are whitish grey, brown, or black. The lower rims of these sheaths are usually black, while their upper rims have 15-40 tiny black teeth (scale-like leaves). These teeth are semi-deciduous and they often break off the sheaths with age. The interior cavity of the central stem is quite large, spanning at least two-thirds of its diameter. The central stem of each fertile shoot terminates in a spore-bearing cone up to 2" long on a short stalk. This cone is ovoid to broadly ellipsoid in shape, and it has a short narrow point at its apex. The cone is densely covered with rows of spore-bearing tubercles; it is usually pale yellow or pale reddish yellow. Instead of a single terminal cone, sometimes an older shoot will produce 1-4 spore-bearing cones on short lateral stalks just below its terminal joint. Infertile shoots are very similar to fertile shoots, except they lack spore-bearing cones. The cones release their spores from late spring to mid-summer; they wither away later in the year. The root system consists of extensive rhizomes with fibrous secondary roots. This plant often forms dense colonies; sometimes these colonies can be quite large in size.


Redwood Forest by water and Pacific Ocean beaches in Crescent City California


Not Edible. Medicinal use for professional herbalists only. Called scouring rush because it was and can be used as a scrub brush. Some people can make them into a flute whistle type instrument. Some Plateau Indian tribes boiled the stalks to produce a drink used as a diuretic and to treat venereal disease.[10] It is used as a homeopathic remedy.[4]

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1 Comment

maplemoth662 3 years ago

A very pretty, landscape photo....

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California, USA

Spotted on Mar 22, 2018
Submitted on Mar 22, 2018

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