This section is from the book "Wayside And Woodland Blossoms", by Edward Step. Also available from Amazon: Wayside And Woodland Blossoms: A Guide To British Wild-Flowers.
When "cool tankards" were more generally compounded than they are to-day, Salad Burnet was a better-known plant, for, like Borage, it formed one of the ingredients. It was used also in the salad bowl, its leaves having a flavour very similar to that of cucumber. It is a perennial, the rosette of radical leaves springing from a stout rootstock. The leaves are all pinnate; the leaflets in pairs, coarsely toothed, and a terminal leaflet. The stems are slender, branched, and the flowers are gathered into a purplish head. They have no petals, and are of two kinds: the upper ones have a four-lobed calyx with a narrow mouth, from which two styles with brush-like stigmas are exserted; the lower bear both stamens and stigmas, or stamens only. The stamens are four in number, attached to the mouth of the calyx, and the anthers hang out. The plant may be found abundantly in dry pastures, especially in a chalk district, flowering from June till August.
The Rough Burnet (P. muricatum), found in cultivated fields in the Midlands and South of England, is probably only a variety of sanguisorba, owing its large size and roughness to the richer soil it finds in the fields.
The Great Burnet (P. officinale), was formerly regarded as constituting a separate genus, Sanguisorba, but it is very similar to the Salad Burnet. Its flowers, however, are all alike, and contain both stamens and pistils. It is much larger than Salad Burnet, and its flower-heads more cylindric, longer, and of a darker purple hue. The stamens, too, instead of hanging far outside the calyx, are no longer than the lobes of that organ. The flowers produce honey, and are fertilized by insects. The leaflets are fewer and longer in this species. Its habitat is damp meadows, and its flowering time the same as Salad Burnet.
The name Poterium is the Latin term for a drinking-cup, in allusion to its use indicated above.
Poterium sanguisorba. - Rosaceae. -