EQUISETUM. Scouring rush, horsetail. Nearly worldwide. The equisetums are primitive plants, distantly allied to the ferns and known mostly by the brushes of thread-like branches lining the stems of some species, known as the horsetails. Others have rush-like stems, often with conspicuous rings at the nodes. They also contain quantities of silica and are rough to the touch. In times past, they were even used for scouring pots and pans. These are attractive and unusual perennials, adding a distinctive touch to poolside plantings and shady nooks. However, many spread ferociously by means of tough rhizomes and are difficult to eradicate. Thus containers of some sort—the stronger, the better—are advisable. Sun or part shade, most soils, moderate to regular watering. The following are hardy to 0^oF or less.

hyemale var. robustum. Scouring rush. Eastern U.S. This is an impressive plant, making dense thickets with jointed, hollow stems up to 10’ high. These are dark green, with greyish bands at the joints. Odd, conelike clusters of spore cases are borne at the stem tips. This is one of the essential plants for the shores of a large pond, and it makes an attractive specimen for tubs.

scirpoides. Dwarf scouring rush. North America. This is one of the smallest of the rush-like species. It produces thick clumps of jointed, wire-like stems, usually 6-8" long, tipped by small club shaped fruiting structures. It is an attractive small container and rock garden subject.