All Floras      Advanced Search
FNA Vol. 9 Login | eFloras Home | Help
FNA | Family List | FNA Vol. 9 | Rosaceae | Potentilla

8i. Potentilla Linnaeus sect. Chrysanthae (Th. Wolf) Juzepczuk in V. L. Komarov et al., Fl. URSS. 10: 180. 1941.

Reidar Elven, Barbara Ertter, James L. Reveal

Potentilla [unranked] Chrysanthae Th. Wolf in P. F. A. Ascherson et al., Syn. Mitteleur. Fl. 6(1): 671, 775. 1904

Perennials, rosetted or tufted, not stoloniferous; taproots not fleshy-thickened; vestiture mostly of long hairs (and crisped hairs in inflorescence), glands absent or sparse to abundant, sometimes red (P. rubella). Stems ascending to erect, not flagelliform, not rooting at nodes, lateral to persistent basal rosettes, (0.2–)1–5(–7) dm, lengths usually 2–5 times basal leaves, rarely shorter than leaves. Leaves: basal not in ranks; cauline 1–3; primary leaves palmate, 3–25(–35) cm; petiole: long hairs spreading to appressed, weak to stiff, glands absent or sparse to common; leaflets (4–)5–11, at tip of leaf axis, ± overlapping or not, narrowly oblanceolate or oblanceolate-elliptic to obovate, margins flat, distal 1/2–3/4+ evenly incised 1/4–1/3(–1/2) to midvein, teeth 1–10(–13) per side, or distal 1/4 or less incised less than 1/10(–1/4) to midvein, teeth 1–2(–5) per side (P. stipularis), surfaces ± similar, green to pale green or reddish, sometimes glaucous, long hairs absent or weak to stiff, cottony hairs absent. Inflorescences (1–)2–20-flowered, usually cymose, open. Pedicels usually ± straight in fruit, sometimes ± curved (P. thuringiaca), 1–3(–6) cm, proximal often much longer than distal. Flowers: 5-merous; hypanthium 2.5–5 mm diam.; petals yellow, ± obcordate, (4–)5–10 mm, longer than sepals, apex retuse; stamens ca. 20; styles subapical, ± columnar, rarely columnar-filiform, to tapered, not or ± papillate-swollen proximally, 0.7–1.3 mm. Achenes smooth to faintly rugose.

Species ca. 8 (3 in the flora): n North America, Eurasia.

1 Cauline leaves: stipules fused with less than 1/3 of petiole, free portion longer than fused portion; basal leaves: distal 2/3–3/4+ of leaflet margins with (4–)6–10(–13) teeth per side; petiole hairs ± spreading, 1–2.5 mm; introduced; Quebec and Rhode Island.   18 Potentilla thuringiaca
+ Cauline leaves: stipules fused with all or most of petiole, free portion shorter than fused portion; basal leaves: distal 1/10–1/2 or less of leaflet margins with 1–2(–5) teeth per side; petiole hairs absent or appressed to spreading, 0.5–1.5 mm; native; Alaska and Greenland   (2)
2 (1) Leaflets 7–11, margins incised in distal 1/4 or less; glands mostly absent.   19 Potentilla stipularis
+ Leaflets (4–)5(–6), margins incised in distal ± 1/2; glands sparse to abundant (especially on pedicels, epicalyx bractlets, and sepals).   20 Potentilla rubella


 |  eFlora Home |  People Search  |  Help  |  ActKey  |  Hu Cards  |  Glossary  |