Knot grass is known by many names, including Knot weed, Bian Xu, Centinode, Ninety-knot, Nine-joints, All seed, Bird's Tongue, Sparrow Tongue, Red Robin, Armstrong, Cow grass, Hog weed, Pig weed, Pig rush, Swynel Grass, and Swine's Grass. The seeds are useful for every purpose in which those of the allied Buckwheat are employed and are produced in great numbers, hence its local name – All seed. Medicinal Actions & Uses: Knot grass has astringent properties, rendering an infusion of it useful in diarrhoea, bleeding piles and all haemorrhages; it was formerly employed considerably as a vulnerary and styptic. It has also diuretic properties, for which it has found employment as an expellant of kidney stones. The concoction was also administered to kill worms.