Sanguisorba L.

Scientific Description

Common name. Sheep's Burnet, Salad Burnet. Family Rosaceae.

Habit and leaf form. Herbs; evergreen. Annual, or perennial. Leaves basal, or cauline. Plants with a basal concentration of leaves; to 0.1–2 m high; rhizomatous. Helophytic, or mesophytic. Not heterophyllous. Leaves medium-sized; not fasciculate; alternate; spiral; not decurrent on the stems; ‘herbaceous’, or leathery; imbricate, or not imbricate; petiolate. Petioles wingless. Leaves sheathing; compound; epulvinate; pinnate; imparipinnate. Leaflets 3–25; 0.5–5 cm long. Lateral leaflets opposite. Leaflets not stipellate; epulvinate; elliptic, or ovate, or obovate, or obtriangular, or orbicular; cordate, or rounded at the base; flat; without lateral lobes. Leaflet margins flat. Leaf blades dorsiventral; pinnately veined; cross-venulate. Mature leaf blades adaxially glabrous; abaxially glabrous, or pilose, or villous. Leaves with stipules. Stipules intrapetiolar; adnate to the petiole (those of basal leaves adnate for entire length, forming membraneous wings; those of cauline leaves basally adnate with free apices); free of one another; ochreate, or not ochreate (partly sheathing the stems); leafy; persistent. Leaf blade margins crenate, or serrate, or dentate (deeply); not prickly; flat. Vegetative buds scaly. Leaves without a persistent basal meristem. Leaf anatomy. Hairs present. Unicellular hairs present. Complex hairs absent. Stem anatomy. Secondary thickening developing from a conventional cambial ring.

Reproductive type, pollination. Fertile flowers hermaphrodite, or functionally male, or functionally female. Unisexual flowers present, or absent (in different species). Plants hermaphrodite, or monoecious, or gynomonoecious, or dioecious, or polygamomonoecious. The unisexual flowers aggregated in different parts of the same inflorescence. Female flowers aggregated in ‘inflorescences’. Male flowers aggregated in ‘inflorescences’. Plants not viviparous; homostylous. Floral nectaries present. Nectar secretion from the disk. Anemophilous (in Western Australia), or entomophilous; via lepidoptera.

Inflorescence and flower features. Flowers aggregated in ‘inflorescences’; not crowded at the stem bases. Inflorescence many-flowered. Flowers in spikes, or in heads. Inflorescences simple. The terminal inflorescence unit racemose, or cymose (rarely). Inflorescences terminal; ascending; compact to dense with long peduncles; with involucral bracts. Flowers subsessile; bracteate; bracteolate; minute; regular; 4 merous. Floral receptacle markedly hollowed. Free hypanthium present; urceolate (constricted at apex; 4-angled); extending beyond ovary. Hypogynous disk present, or absent. Perianth sepaline; 4; 1 -whorled. Calyx present; 4; 1 -whorled; polysepalous. Calyx segments entire. Calyx erect; glabrous; imbricate; green, or white, or red; non-fleshy; not persistent. Sepals oblong, or ovate, or obovate. Corolla absent. Androecium present. Androecial members definite in number, or indefinite in number. Androecium 2–4, or 12, or 48 (approx.). Androecial members free of the perianth; all equal; free of one another. Stamens 2–4, or 12, or 48 (approx.); attached inside the hypanthium (in throat); becoming exserted, or remaining included; all more or less similar in shape; reduced in number relative to the adjacent perianth, or isomerous with the perianth, or polystemonous; alternisepalous, or oppositisepalous; inflexed in bud. Filaments not geniculate; glabrous; filiform, or club-shaped. Anthers all alike; dorsifixed; versatile; dehiscing via longitudinal slits; tetrasporangiate. Pollen grains psilate. Gynoecium 1–3 carpelled, or 5 carpelled. The pistil 1–3 celled, or 5 celled (2 in Western Australia). Carpels reduced in number relative to the perianth, or increased in number relative to the perianth. Gynoecium monomerous, or apocarpous; of one carpel, or eu-apocarpous; superior. Carpel stylate; apically stigmatic. Style straight. Carpel 1 ovuled. Placentation apical. Ovary summit glabrous. Styles simple; becoming exserted, or not becoming exserted; deciduous. Stigmas much-branched, fimbriate or pubescent. Ovules pendulous; non-arillate; anatropous.

Fruit and seed features. Fruit 3–8 mm long; non-fleshy; brown; not hairy; an aggregate. The fruiting carpel indehiscent; an achene. Fruit 1 celled. Dispersal unit the fruit. Dispersal by animals or wind. Fruit 1–3 seeded, or 5 seeded. Seeds 1 per locule. Seeds non-endospermic; compressed; small. Cotyledons 2; folded (plano-convex). Embryo straight. Testa hard; non-operculate; smooth, or with tubercles (pitted). Seedling. Cotyledon hyperphyll assimilatory.

Geography, cytology, number of species. World distribution: Mainly Eurasia, North Africa and North America; naturalised in Australia. Adventive. Australian states and territories: Western Australia, or South Australia, or Queensland, or New South Wales, or Victoria, or Australian Capital Territory, or Tasmania. South-West Botanical Province. X=7; ploidy levels recorded 4, or 8. A genus of 10 species; 1 species in Western Australia; Sanguisorba minor Scop.

Economic uses, etc. Used in salads, as a fodder plant, purported to staunch bleeding.

Additional comments. Some species of Sanguisorba are insect pollinated, with inflorescences having all perfect flowers, stamens short and stiff, stigmatic branches short and compact and a prominent nectar ring. Other species are wind pollinated having inflorescences with flowers a combination of perfect and imperfect, stamens filiform and long exserted, stimatic branches penicillate and the nectar ring almost lacking.

Additional characters Pollen grains 6 or 3 colporate.

Etymology. From the Latin sanguis, "blood", and sobere, "to absorb", pertaining to the use of the type species as an astringent.