How do you kill Equisetum or otherwise known as horsetail?

Answer 1

Reliable sources report that equisetum grows rhizomes to depths of six feet, although many anecdotal reports exist for depths of twice this depth or more. If your equisetum has appeared only recently, it will have a fairly shallow root depth, and glyphosate may be effective at the maximum label rate, particularly if applied repeatedly. Glyphosate will have little effect on established equisetum as the plants will have considerable "reserves" in the form of carbohydrates stored in tubers and rhizomes at a greater depth in the soil than a first-season occurrence of the plant. Repeated burning or cutting of horsetail forces its continued growth, eventually exhausting its carbohydrate stores. This process can take years for well-established equisetum stands. Equisetum thrives in wet, acidic, sunny locations. Therefore, applying lime, improving drainage, and applying fertilizer to accelerate the growth of grasses in mixed stands serves as a cultural control. Equisetum does not respond significantly to additional nitrogen, giving grasses an advantage.