Mares Tail (also known as Horse Tail)
Mares tail generally prefers moist and shady areas but is can increasingly be found on waste ground and non-cropped areas. Mares tail is an invasive, deep-rooted weed with fast-growing rhizomes (underground stems) that quickly send up dense stands of foliage.
In spring, it produces light brown stems up to 20-50cm (10-20in) tall which appear as a cone like structure which produces spores at the end of the stems.
Mares Tail is easily recognised by its upright, fir tree-like shoots that appear in summer and reach up to 2 ft tall.
It has a thick waxy cuticle and small needle-like leaves that make it difficult to get sufficient spray into the plant to kill the roots. Repeated cutting will weaken rhizomes but is generally ineffective on its own as horsetail has a deep root system..
TREATMENT
Diamond is a total weed killer and will kill mares tail, weeds and grass in about 7-10 days. It will kill the horsetail systemically, right through to the root and treated plants will not grow back. You may need to treat new plants that grow from untreated roots, but once sprayed they too will be completely controlled.
Sprayed mares tail usually takes 1-2 weeks to appear as if it is dead, but it will take longer to rot down and disappear. Only once it has died and disappeared is the grass safe to graze or bale for hay.