Scouring Rushes Were The First Scouring Brushes Roy examines a large patch of tens of thousands of tall scouring rushes. It was Robert Marcellus, principal clarinetist with the Cleveland Orchestra, and also with the Peninsula Music Festival orchestra in Door County during the summer, who approached me one day with an unusual request when I was working at the Ridges Sanctuary at Baileys Harbor. "Do you happen to know the whereabouts of some rather thick robust scouring rushes?" Naturally my interest was immediately aroused as I asked him why he was looking for these unusual plants. "I use the individual dried sections as miniature cylindrical sanding devices for shaping my clarinet reeds. The natural abrasives in these plants are as fine and perfect for this job as any manufactured item." Fortunately I was aware of a small patch of tall scouring rushes, also referred to as horsetails, and one two-foot-tall plant was all he needed. It was exactly the species he had hoped we would find. A few weeks ago, having to go to the University of Wisconsin at Green Bay, I decided to take my camera and get some photographs of a large patch of tall scouring rushes growing within ten feet of the highway in southern Door County that had been attracting our attention for twenty or more years. It is a patch growing in the shade in sandy soil at the base of a wooded hill where the plants apparently receive a constant seepage of moisture. I decided to snip off two of the plants, among tens of thousands, and take them home for further examination. They are around 32 inches long, have between 12 and 14 sections, each averaging between two to three inches in length. Having dried, the sections are now extremely abrasive and will easily remove surface material from one of my thumbnails. Here is what makes these scouring rushes so abrasive. Rain falls to the ground and, in doing so, absorbs carbon dioxide from the air which in turn forms a weak solution of carbonic acid in the raindrops. Through the years this constant addition of acid to the wet sandy soil, in which the scouring rushes grow, slowly dissolves some of the sand which is primarily silicon dioxide or quartz. This quartz in solution within the sandy soil is now taken up by these plants and hardens in the outer cell walls into what can be referred to as amorphous quartz that lacks definite form or shape. If one were to take an individual section of a tall scouring rush and carefully suspend it by the end in a container of acid overnight, by morning all that will remain will be the delicate cylindrical form of the uncrystallized quartz, the very fragile glass-like skeleton of the section. Scouring rushes belong to a plant group frequently referred to as horsetails. Its genus name, Equisetum (ek-wi-SEE-tum), is derived from the Latin "equus," meaning horse, and "seta," meaning bristle. This is in allusion to some of the species’ thin leaves which, when bunched together, do resemble a small green horse’s tail. They are segmented and not related to true rushes, which reproduce from seeds, and are extremely far removed from horses! They do not have flowers, instead reproducing from spores as well as from rhizomes situated on the roots. Most people show considerably less interest in plants that do not have flowers. Unfortunately they are missing out on some fascinating and very primitive plants. Modern horsetails date back to somewhat over 200 million years ago. Fossils of tree-sized horsetails indicate that they flourished on Earth more than 400 million years ago. There are some excellent specimens of these fossils in the Third World exhibit at the Milwaukee Public Museum. Imagine a great southern swampland containing hundreds of square miles of wetlands, such as the great Okefenokee Swamp in southern Georgia and northern Florida. Tree-sized horsetails, as tall as 40 to 50 feet, growing in such a swamp for hundreds of years, triggered the development of extensive peat bogs. These in turn produced the vast coal-fields of today. Today’s horsetails, which are allies to the ferns and clubmosses, also spore-producers, are rarely taller than three to four feet. Only about 25 species exist in the entire world, making it an easy plant group to study. Eleven species can be found in Wisconsin. The kind most people see and recognize is the tall scouring rush, very likely the species that the Native Americans, and later the pioneer women who learned from the Indians, tied together into fist-sized bundles for use in scouring their pots and pans blackened by the fires—hence the name of scouring rush. The fact that the stems contain tiny raised ribs running from top to bottom increases their effectiveness as scouring material. It is my guess that no plants indirectly, in the form of coal, used by people date farther back into history than the horsetails. This column appeared in the Door County Advocate on 12/15/2000. © Copyright 2000 Roy Lukes. All rights reserved.