Field Horsetail Frequently Asked Questions

What is Field horsetail?

Field horsetail (Equisetum arvense) also known as Bottlebrush plant, Cat’s tail, Pipe weed and commonly miscalled Mare’s tail is a native perennial weed that can be found growing throughout the UK.

What does Field horsetail look like?

Field horsetail appears light green in colour with a mass of spindly, very thin leaves growing from a single stem. The entire plant has a rough texture due to the presence of silica within the stem and leaf structure. Field horsetail growth will vary in size but will typically range 5-60cm in length. Appearing in March-April as tough, light brown/white stems, Field horsetail will produce spore-bearing bodies that ripen and shed their spores in late April then die back. Soon after the light green stems will appear and cover much of the surrounding area, dying back above ground completely in winter.  Field horsetail can also reproduce using underground creeping stems or rhizomes, extending up to 2 metres in depth and 1.5 metres in width from the parent plant.

Why is Field horsetail a problem?

Field horsetail is a highly invasive species that is capable of rapidly colonising many adverse areas, requiring very little nutritional content and slight water content from the ground it is present on. It can be found growing in some of the most unusual and seemingly barren places, from marshland to rubble piles. Due to its messy appearance, Field horsetail can spoil the aesthetic qualities of a well kept garden but can also adversely affect the biodiversity of the surrounding area by consuming local resources and thereby denying them to its neighbours.  Field horsetail poses a threat to animals (see below).

What damage can Field horsetail cause?

It is the ability to rapidly colonise areas that makes Field horsetail a serious threat to local plant populations, out-competing other plant species and threatening biodiversity. The lack of certain plant species that would have otherwise thrived in an area had it not been for the presence of Field horsetail can have dramatic effects for local wildlife. Field horsetail is also a toxic plant which can poison and potentially kill livestock unfortunate enough to graze on it, posing a serious danger to cattle, sheep and ironically (due to its name) horses.

How can you kill Field horsetail?

Field horsetail can be controlled with professional application of suitable herbicides although a majority of domestic weed killers will not result in complete eradication. It is also possible to eliminate Field horsetail by careful control of the nutrient and pH levels of the soil where it is found, however this must only be carried out by experienced individuals to reduce the risk of damage to the surrounding ecosystem. Excavation of Field horsetail is also possible but should only be attempted by trained persons due to the extensive underground rhizome network.

How can I prevent Field horsetail spreading?

The main priority when attempting to control Field horsetail is to minimise unnecessary disturbance. Field horsetail is able to regenerate from cuttings of its leaves so any inexperienced handling of the plant will only increase the chances of spreading. The ground on which Field horsetail is present will contain a potentially vast underground network of rhizomes that are capable of producing new growth from tiny fragments. It is all too common for amateur excavations of Field horsetail to result in not only increasing the coverage of the target infestation but also inadvertently spreading the weed to other areas nearby.