Indeterminate nodules are the only type found in Caesalpiniodeae and Mimosoideae and the most common type in Papilionoideae (Sprent, 2001; p. 32). As a result of the variety of ways the plant is infected by rhizobia, there are different types of nodules.
Vitamins are organic compounds that are needed in even smaller quantities than minerals by the horse, although no less critical. Vitamins can be divided into two groups, the fat soluble vitamins A, D, E and K and the water soluble C and B-complex vitamins.
However, horsetail is valued more for its health benefits due to a number of great minerals and other nutrients it contains, such as manganese, calcium, iron, flavonoids, caffeic acid esters, saponins, tannins, alkaloids, fatty acids, phytosterols, glycosides, phenolic acids, aconitic acid, and silica.