Horsetail makes up a persistent group of weeds that have been in existence for millions of years. Pulling this weed often results in forcing the underground portion to grow in new directions. Although it is a weed, horsetail does have some uses that make it a beneficial plant, as long as it's not taking over your garden or field crops.
Horsetail weeds are also called scouring rush, marestail, snake grass and horse pipes. They're often ignored as they grow along the edges of ponds and roadways, but when they encroach on desirable plants, they become a nuisance. Horsetail is characterised by hollow, jointed stems that are rough in texture. The fertile stem is typically branchless and light brown in colour. The sterile stems grow to 2 feet in height with green, leaflike branches that form at the joints. These sterile stems begin growth as the fertile stems disappear in late autumn. Horsetail weed does not appear to have leaves because it's extremely small.
Horsetail reproduces by spores and does not have flowers. Its deep root system produces several stems, making it appear as more than one plant. Although it prefers wet environments, horsetail weeds can move to drier soils and continue to grow.
The growing tips of horsetail can be stir fried with vegetables and meat to add flavour. Some animals also eat horsetail weed -- although this weed can be deadly to horses. It has also been used by campers to clean frying pans because of its rough texture, giving it the nickname, "scouring rush."
In proper growing conditions, most desirable plants and crops can compete successfully with horsetail weeds. Weak plants, however, may not be strong enough to handle the competition for nutrients and water. In gardens, the appearance of horsetail is unappealing, and when grown with crops and in fields, horsetail can be toxic if eaten by horses, sheep and cattle. Equisetosis, primarily affecting horses, can result if the horsetail is ingested. This poisoning causes breathing and heart problems, fever, digestive issues, convulsion and may cause death.
Prevention and Control
Control of horsetail weed is difficult, so prevention is important. Avoid light tilling of the soil in areas near where horsetail grows, as light tilling can spread seeds -- and root parts that aren't caught by the blades can regrow. Irrigate poorly drained soil near ditches, ponds and low sections of land. There are few herbicides that effectively control horsetail weeds because of their deep root system and the lack of leaf area to take up the chemicals in high enough levels to kill them. Glyphosate may suppress horsetail, but only for short-term periods. Regrowth is likely to occur. To eradicate a patch of horsetail, several applications will be required.