Horsetail

Field horsetail (Equisetum arvense) is often confused with Mare's tail (Hippuris vulgaris). Although superficially looking similar, they are very different with the former having a wide range of habitats and the latter preferring aquatic habitats. The stems are slender with the leaves being very fine protruding as whorls of long rough hair like structures forming a horsetail like structure. These plants have deep roots (rhizome) and spread via microscopic spores.

Field horsetail is native to the UK and is not an invasive non-native species. However, it can be considered a nuisance weed as a result of it growing through gaps in paving, cracks in driveways and general persistence in landscaped areas. In countries such as New Zealand where it has been introduced it is an invasive non-native species and can impact on agriculture and natural ecosystems.

The plant is difficult to control using herbicides due to the fine leaves which result in reduced absorption of the active ingredients and although the top of the plant may initially be controlled, it will eventually re-emerge from the deep rhizome. Mechanical removal can remove the weed, but the rhizome can go down several metres into the soil and if locally abundant can require large volumes to be removed. It should be remembered that this plant is native, abundant and spreads via spores making long term management necessary to minimise impact.