Equisetum (Horsetail, Mare’s Tail, Scouring Rush) (prepared by Gwen Heistand for ACR Education) Equisetum … Folks have been asking about the horsetail reproductive structures that can be seen at many places on the preserve in March. What you are seeing are the strobili (singular strobilus) with whorls of hexagonal scales. Sporangia (or sporangiophores, containing spores) attach to the scales. One neat thing about equisetum spores … each one has four unique strap-like structures called elaters that attach at a common point. These elaters expand and contract with changes in humidity. When it is dry, elaters spread out, promoting release from sporangia and wind-dispersal. Under moist conditions, the elaters tightly hug the spores, encouraging them to stay put. Equisetum also reproduce vegetatively along rhizomes. A single rhizome clonal system may cover hundreds of feet. This ability helps equisetum rapidly colonize disturbed areas. Equisetum formed huge monotypic stands in the newly deposited material after Mt St. Helens’ eruption in 1980. (The photograph was taken from along the Fern Trail in Volunteer Canyon) Equisetum Page 1 Equisetum (Horsetail, Mare’s Tail, Scouring Rush) (prepared by Gwen Heistand for ACR Education) Another cool thing about Equisetum is its ability to accumulate silica in its tissues – giving the plant its rough texture. Ask kids how this might benefit the plant… Some studies have shown that silica solutions applied to plants protect them from fungal diseases and insect attack. Some gardeners use equisetum extract to protect plants from pathogens and herbivores. As you all know, this is where they get the name “scouring rush”. Some species are reported to be equivalent to the finest grades of steel wool in polishing wood finishes and were used by European cabinet makers. Native Americans used horsetail to produce dyes. (layer wool or yarn with Horsetail using about a 10:1 ratio of Horsetail:yarn, boil 30 minutes, then dry in the shade.) Early Irish peoples used Equisetum dyes as well. I’ve read that in early Ireland dyeing was considered to be a magical process. It was a women’s craft and there was a taboo against dyeing fabric in the presence of men and also rules about which days of the month or week were proper for dyeing. Dyers also had a reputation for being herbal healers, since many dyestuffs were used in folk medicine. Native Americans also made a diuretic tea from horsetail. [Photo by Dustin Kahn of yarn she dyed. Today silica extracted from horsetail is still used in diuretic (clockwise from top): Horsetail, Toyon, and medicinal products (kidney and bladder stones, urinary California coffeeberry, California sagebrush, tract infections, incontinencel; balding; tuberculosis; Black walnut] jaundice; hepatitis; brittle fingernails; joint diseases; gout; osteoarthritis; weak bones (osteoporosis); frostbite; weight loss; heavy menstrual periods; and uncontrolled bleeding (hemorrhage) of the nose, lung, or stomach. Horsetail is applied directly to the skin to treat When you come upon Horsetails wounds and burns. Other modern uses include abrasives, with kids … what questions might toothpaste, protective cloth, optical fibers, paint you ask? thickeners. Chemicals found in leaf odors were used in the What does this plant feel like? 1970’s in perfumes. Today they are used as food flavors, Does it smell? flavor enhances, and as animal repellants. Where did you find it? (All of these modern uses were taken from WebMD.) What else is growing around it? If you had to name this plant – what The Horsetail genus (Equisetum) is an ancient genus. During would you call it? the Carboniferous age Does anyone know how native peoples (more than 230 million used this plant? years ago), Horsetails Who do you think might eat it? Does it produce flowers? were the dominant How does it reproduce? plant group reaching How long do you think relatives of this gigantic sizes. plant have been on the earth? Calamites, well-known fossils from this period, are stems of gigantic horsetails. Equisetum Page 2 .