Horsetail is somewhat similar in appearance to asparagus, and its stems are bushy, giving the appearance of a horse's tail. The roots contain tuber-like growths which are high in starch. Horsetail reproduces by spores produced in a cone at the terminal end of each stock. It is commonly found on moist, sandy soil. Horsetail contains several poisonous chemicals and is especially high in silica.
Horses are particularly sensitive to horsetail poisoning.
However, most cases of poisoning occur when it is fed in hay. Control Horsetail can be controlled after it emerges with MCPA Ester. It is important to use this specific formulation of MCPA since the other formulations of both 2,4-D and MCPA are not readily taken up by the plant. Other herbicides which control horsetail when applied in the fall include Ignite, Lorox, Casoron, Hyvar, Oust and Tiller. This article is the fourth in a series on practical farm records using examples from the ICPM Record Keeping System.