Herbs, perennial, 4–10 dm, glabrous or hairy, hairs simple and glandular; rhizomatous, rhizomes horizontal, woody. Stems 1–5, proximal to inflorescences, erect to ascending, usually red when young, usually simple. Leaves persistent, basal and cauline, ternate; stipules depressed-ovate or linear, margins serrate, doubly serrate, shallowly laciniate, incised, lobed, or dissected; petiole present or absent; blade trullate to widely trullate, 3–9 cm, herbaceous, leaflets 3, lanceolate to ovate-oblong, 4–8 cm, margins flat, incised, doubly serrate, teeth gland-tipped, variably glandular and hairy. Inflorescences terminal, 3(–9)-flowered, loose, leafy panicles; bracts present; bracteoles absent. Pedicels present, 1–7 on each branch. Flowers 10–20 mm diam.; hypanthium often red or purple, 4.5–8 mm, glabrous; sepals 5, erect, triangular-ovate; petals 5, white to pale rose, linear-lanceolate, unequal; stamens 20 (in 3 whorls), shorter than petals; styles filiform, glabrous, stigmas capitate. Fruits aggregated follicles, 5 (1–5 maturing), broadly ovoid to broadly elliptic-ovoid, slightly flattened, 4.5–8 mm, strigose to villous-strigose, glabrous, or glabrate, partially dehiscent abaxially and partially adaxially; hypanthium persistent; sepals persistent, erect to loose spreading at apices. Seeds 2 per follicle, light brown to reddish, longitudinally rugulose, glabrous. x = 9.

Distribution

North America.

Discussion

Species 2 (2 in the flora).

Porteranthus Britton, a superfluous and illegitimate name, was proposed by N. L. Britton in 1894 as a substitute for Gillenia because the similar name Gillena had been used by Adanson in 1763. Both names refer to Arnold Gillen. A proposal to conserve Gillenia (D. R. Hunt 1982) was opposed by K. R. Robertson (1983); a vote (E. G. Voss 1986) indicated that the two names are not confusable.

Selected References

Evans, R. C. and T. A. Dickinson. 2005. Floral ontogeny and morphology in Gillenia ("Spiraeoideae") and subfamily Maloideae C. Weber (Rosaceae). Int. J. Pl. Sci. 166: 427–447.

Lower Taxa

Gillenia stipulata, Gillenia trifoliata

Key

1	Stipules depressed-ovate, persistent, 10–20(–25) × 10–20 mm; leaflets: abaxial surfaces densely glandular; follicles glabrous or glabrate.	Gillenia stipulata
1	Stipules linear, deciduous, 3–8 × 1–3 mm; leaflets: abaxial surfaces eglandular or sparsely glandular; follicles strigose to villous-strigose.	Gillenia trifoliata