Stems: annual, hollow, jointed, provided with scattered stomata, the fertile appearing in early spring before the sterile. Leaves: reduced to sheaths at the joints.

This is a rush-like plant of a very rank coarse nature, which grows in ditches and along the sandy waysides. The fertile stems, which appear in the early spring, grow from four to ten inches high and are light brown in colour. They are not branched, but terminate in a solitary cone-like spike. The sterile stems, which appear later on in the season, are green and rather slender, averaging eighteen inches in height. They have numerous verticillate branches, the sheaths of which are four-toothed.

Eqiiisetum pratcnse, or Thicket Horsetail, has many more cup-shaped sheaths on the fertile stems (which become branching when old) than the preceding species; also its branches are more or less horizontal, those of the Field Horsetail growing upwards.

Equisetum sylvaticiim, or Wood Horsetail, has furrowed stems, and compound branches; the tiny branchlets curving downwards.

Eqiiisetum scirpoidcs, or Rush Pipes, has evergreen, perennial, slender, furrowed stems, which grow in tufts from the subterranean rootstock.

Eqiiisetum fluviatile, or Swamp Horsetail, is a large, coarse plant found, as its name denotes, in very wet places. It has a big central cavity in the stem, hollow branches, and a hollow rootstock.

Equisetum varicgatum, or Varigated Horsetail, has rough, perennial, evergreen stems, growing in tufts, and resembles Rush Pipes, being, however, a much taller plant.

Equisetum hyemale, or Scouring Rush, has stiff, slender stems, and pointed spikes. Its name denotes that it is used by European peasants for scouring floors.