Horsetails are plants of such ancient ancestry that they belong to a botanical class of their own. They have been used as cleansers from the earliest times as they contain large quantities of silica from the soil which is redeposited in their stems as fine crystals and makes an ideal cleansing agent. Although invisible to the human eye, the crystals are substantial enough to make a horsetail feel like fine sandpaper if one of them is run through the hand.

Throughout the ages horsetails have been used for a variety of purposes. Dairymaids used to scour their milk pails with them and the North American Indians used them to smooth the shafts of their arrows. Knights used them for polishing their armour, and some watchmakers even used them to give an extra smoothness to the works and casing of their watches.

Horsetails were eventually given the common name of pewterwork when they began to be used regularly for scouring household pots and pans as a precursor to wire wool.

Common horsetails can be found on poorly drained land between May and October and are recognisable by their jointed stems and bristly fonds.