Rough cinquefoil

Description

Potentilla norvegica is a species of cinquefoil known by the common names rough cinquefoil, ternate-leaved cinquefoil, and Norwegian cinquefoil. It is native to Europe, Asia, and parts of North America, and it can be found elsewhere as an introduced species. Norwegian cinquefoil is usually an annual but may be a short-lived perennial. It produces a basal rosette of leaves from a taproot, then a green or red stem growing erect up to about 50 cm (20 in) in maximum length, and branching in its upper parts. The leaves are stalked and are either divided into five leaflets, or have three leaflets with the terminal leaflet being divided into three lobes. The basal leaves have narrow, sharp-tipped stipules while the upper leaves have elliptical stipules which are longer than the leaf stalks. Each leaflet is up to 5 cm (2 in) long and is widely lance-shaped with toothed edges. The inflorescence is a cyme of several flowers. Each flower has five rounded yellow petals no more than 4 mm (0.2 in) long inside a calyx of hairy, pointed sepals with reddish tips. There are twenty stamens, a separate gynoecium and many pistils. The calyx lengthens after flowering and the fruit is a cluster of pale brown achenes. Norwegian cinquefoil is native to much of Europe, Asia, and parts of North America, and it can be found in other parts of the world as an introduced species. Its natural habitat is arable fields, gardens, banks, hedgerows, wasteland, logging clearings, loading areas and occasionally shores, often on sandy or gravelly soils. Potentilla is a genus containing over 300 species of annual, biennial and perennial herbaceous flowering plants in the rose family, Rosaceae. Potentillas may also be called cinquefoils in English, but they have also been called five fingers and silverweeds. Some species are called tormentils, though this is often used specifically for common tormentil (P. erecta). Others are referred to as barren strawberries, which may also refer to P. sterilis in particular, or to the closely related Waldsteinia fragarioides. Several other cinquefoils formerly included here are now separated in distinct genera - notably the popular garden shrub P. fruticosa, now Dasiphora fruticosa.