Plants of the Eloise Butler Wildflower Garden

Rough Cinquefoil is an erect forb that can be annual, biennial or a short lived perennial. It begins life with a basal rosette, later sending up a flowering stalk from 1 to 3 feet high. The stem is leafy, hairy, and usually branched near the top, green initially then turning to a dull reddish-purple. Lower stem hairs are usually stiff and usually without glands. There are both Eurasian and native populations found in North America.

Leaves, both basal and on the stem, are slightly hairy on top, more so on the underside, are 3-parted with each elliptical to oval leaflet 2 to 3 inches long, tapering to the base, with slightly rounded edges on the teeth, some of which are double. The basal leaves have long hairy leaf stalks while the stem leaves are alternate with shorter stalks. The uppermost leaves are stalkless.

The inflorescence is a tight branched cluster (a cyme) or clusters, as several may form on the upper branches. Solitary flowers also occur from the upper leaf stalks.

Flowers: Each pale yellow 5-parted flower is only 1/3 to 1/2 inch wide with gaps between the 5 yellow petals through which appear the 5 green hairy calyx lobes (sepals) that are longer than the petals. Petals are obovate in shape (widest in the center, length about 1.5x the width) and widely spaced. Just below the sepals are 5 still longer green spreading bracts that are more triangular shaped. The flower has 15 or 20 stamens with yellow filaments and broad yellow anthers in a circular pattern around a dome shaped center receptacle containing 60 to 150 carpels with their thread-like styles. Flowers do not all bloom at once, giving an extended bloom period of a month or more for the plant.

Seed: In fertile flowers, the long calyx lobes (sepals) fold upward and over the flower head forming a cone like protective structure until the seeds (dry flattened achenes without a pappus) are mature and are scattered from the plant by wind action on the tall stem. Regeneration is from re-seeding. The achenes are tan to brown, 0.8 to 1.3 mm long.

Habitat: Rough Cinquefoil is found in many sites, from dry to slightly moist soils, in full sun to partial shade. As it regenerates from seed, it usually takes hold along edgeways where seedlings are not crowded out by more vigorous perennial vegetation. Native North American populations prefer more moist sites

Names: The genus name, Potentilla, is from the Latin word potens, meaning 'powerful' and refers to the medicinal power of some species of the genus which have medicinal properties. The species name, norvegica, means "of Norway" and perhaps is a reference to whose settlers brought the plant to North America. The old common name of Strawberry Weed is due to the similarity of the leaves of a young plant to the common strawberry. The author name for the plant classification from 1753 - 'L.' refers to Carl Linnaeus (1707-1778), Swedish botanist and the developer of the binomial nomenclature of modern taxonomy.

The Pontentilla are are large genus of about 400 species. These have been separated into sections. P. norvegica is in section Rivales which is composed of those species that are primarily annuals, biennials, or short-lived perennials. See Flora of North America (Ref. #W7) for a complete key.

Comparisons: Another non-native Cinquefoil that is similar to this species is P. recta, the Rough-fruited Cinquefoil. But there the lower leaves are 5 to 7 parted and the flower sepals and bracts are much shorter than the petals.