Rough cinquefoil (upright cinquefoil, yellow cinquefoil, Norwegian cinquefoil)
Stems & Roots: 20-50cm (8-20in.) high, usually branched, sometimes with 2 or more stems from the same root, hairy throughout.
Leaves: Alternate (1 per node), compound; 1 leaf consisting of 3 leaflets at the end of a leafstalk (petiole) and a pair of stipules at the base of the leafstalk where it joins the stem; each leaflet oblong to roundish with coarse, sharp, forward-pointed teeth; leaves in a rosette early in the growing season and, at this stage, frequently mistaken for strawberry; lower stem leaves long-stalked; uppermost leaves stalkless with the 3 leaflets and pair of stipules apparently attached directly to the stem.
Flowers & Fruit: Flowers about 6mm (1/4 in.) across, on short stalks from leafy branches in the upper part of the plant; 5 pale yellow petals about the same length as the green sepals, a ring of many stamens around the cluster of many tiny pistils which mature into a cluster of seeds; each seed about 1mm (1/25 in.) long, yellowish to pale brown and ridged lengthwise. Flowers in June and July.
Habitat: Rough cinquefoil occurs throughout Ontario in pastures, meadows, waste areas, roadsides, and occasionally in gardens and cultivated fields.
Similar Species: Rosettes of Rough cinquefoil are distinguished from strawberry plants (Fragariaspp.) by having teeth all around the margins of all 3 leaflets, whereas with strawberry the lower 1/4 to 1/3 of each leaflet is usually without teeth. Older plants have robust, erect stems with several leaves and yellow flowers, whereas strawberry has a slender, short, nearly leafless stem with loose clusters of white flowers. It is distinguished from the yellow-flowered buttercups by its 3-leaflet leaves and the presence of a pair of stipules at the base of each leafstalk. Rough cinquefoil is distinguished from other cinquefoils by the combination of 3-leaflet leaves green on both surfaces, and small (6-10mm, 1/4-2/5 in. across), pale yellow flowers in which the sepals and petals are of about equal length.