Yellow Avens

This species is used medicinally and as a source of oil.

Roots fascicled, fibrous. Stems erect, 30–100 cm tall, together with petioles spreading rigid hairy, rarely glabrescent. Radical leaves lyrate-pinnate, 5–15 cm including petiole, usually with 2–6 pairs of leaflets, both surfaces sparsely rigid hairy; leaflets unequal, terminal one largest, broadly rhombic-ovate or compressed orbicular, 4–15 × 5–15 cm, base broadly cordate to cuneate, margin usually irregularly coarsely serrate, apex obtuse or acute; cauline leaves: stipules green, leaflike, ovate, large, margin irregularly coarsely serrate; leaf blade pinnate, sometimes repeatedly lobed; terminal leaflet lanceolate or obovate-lanceolate, base cuneate, apex often acuminate or shortly so. Inflorescence terminal, lax. Flowers 1–1.7 cm in diam.; pedicel pubescent or hirtellous. Sepals ovate-triangular, apex acuminate; epicalyx segments lanceolate, minute, ca. 1/2 as long as sepals, abaxially pubescent and villous, apex acuminate, rarely 2-fid. Petals yellow, suborbicular, longer than sepals. Style terminal, twisted at joint ca. 1/4 way from apex; proximal section pilose; distal section deciduous at fruit maturity. Achene aggregate obovoid; fruiting receptacle hispidulous, hairs ca. 1 mm; achenes hirtellous; proximal section of style persistent, glabrous, apex hooked. Fl. and fr. Jul–Oct.

Gansu, Guizhou, Heilongjiang, Henan, Hubei, Jilin, Liaoning, Nei Mongol, Shaanxi, Shandong, Shanxi, Sichuan, Xinjiang, Xizang, Yunnan [widespread in N temperate zone].

Forests, open places in forests, grassy mountain slopes, river and stream banks, fields; 200--3500 m.

Geum aleppicum var. bipinnatum (Batalin) Handel-Mazzetti; G. intermedium Besser ex Marschall von Bieberstein (1808), not Ehrhart (1791), nor Willdenow (1806), nor Tenore ex Nyman (1878); G. potaninii Juzepczuk; G. strictum Aiton; G. strictum var. bipinnatum Batalin; G. vidalii Franchet & Savatier.

Geum strictum Ait. Hort. Kew. 2: 217. 1789
Geum canadense Murr. Novi Comm. Gott. 5: 33. 1775. Not G. canadense Jacq. 1773. Geum heterophyllum Link, Enum. 2: 65, as synonym. 1822. Geum scopulorum Greene, Pittonia 4: 148. 1900.
Perennial, with a short rootstock; stem 5-15 dm. high, strongly hirsute, especially below, also finely puberulent in the inflorescence; basal leaves interruptedly lyrate-pinnate; rachis more or less hirsute; principal leaflets 5-9, cuneate, obovate, or on the young shoots the terminal leaflet rounded or reniform, 2-10 cm. long, variously cleft or divided and double-toothed, more or less pubescent on both sides or glabrate; lower stem-leaves similar, the uppermost 3-foliolate and short-petioled; inflorescence few-flowered with ascending branches; bractlets linear, one-third as long as the sepals; sepals lanceolate, acuminate, reflexed, about 6 mm. long; petals orbicular, 5-8 mm. long, bright-yellow; receptacle densely short-pubescent; fruiting head 15-18 mm. in diameter; body of the achenes 3-4 mm. long, appressed-pubescent throughout and hispid towards the apex ; lower internode of the style 4-5 mm. long, glabrous throughout, or sparingly hispid at the base; upper internode 1.5 mm. long, hirsute with hairs 0.5 mm. long.
Type locality: North America.
Distribution: Low meadows, from Newfoundland to Pennsylvania, Missouri, Mexico, and British Columbia. The European and Asiatic plant known under this name is probably distinct.

Geum decurrens Rydberg, sp. no v
Perennial, with a short rootstock; stem more or less pubescent, but not conspicuously hirsute; basal leaves similar to the lower stem-leaves, but the terminal division sometimes much broader and more rounded; lower stem-leaves interruptedly pinnate, sparingly pubescent; leaflets 5-9, oblanceolate to obovate, more or less decurrent on the rachis, the upper ones more or less confluent, 1-5 cm. long, cleft and more or less doubly toothed; upper stem-leaves ternate and short-petioled; inflorescence corymbiform with short branches; bractlets lanceolate, half as long as the sepals; sepals triangular-lanceolate, 5-6 mm. long; petals orbicular or broadly oval, about 6 mm. long; receptacle pubescent; body of the achenes 3-4 mm. long, pubescent, hirsute above; lower internode of the styles glabrous, the upper short-hirsute.
Type collected at Baker's Butte, Mogollon Mountains, Arizona, July 28, 1887, Edgar A. Mearns 59 (herb. N Y. Bot. Gard.; dupl. in herb. Columbia Univ.). Distribution: Arizona, New Mexico, and Colorado.

Flowering and fruiting from July to October.

Geum aleppicum is close relative of Geum japonicum var. chinense, but differs from the latter in its receptacle hispidulous (vs. hirtellous), hairs ca. 1 mm (vs. 2-3 mm); cauline leaves 2-6-foliolate, sometimes repeatedly pinnatifid (vs. upper cauline leaves usually simple, entire or 3-lobed); terminal leaflet of radical leaves broadly rhombic-ovate or obovate-lanceolate (vs. ovate to broadly obovate), apex usually acuminate (vs. rounded).

Geum aleppicum is occurring in Gansu, Guizhou, Heilongjiang, Henan, Hubei, Jilin, Liaoning, Nei Mongol, Shaanxi, Shandong, Shanxi, Sichuan, Xinjiang, Xizang, Yunnan of China, widespread in N temperate zone.

Roots fascicled, fibrous. Stems erect, 30-100 cm tall, together with petioles spreading rigid hairy, rarely glabrescent. Radical leaves lyrate-pinnate, 5-15 cm including petiole, usually with 2-6 pairs of leaflets, both surfaces sparsely rigid hairy; leaflets unequal, terminal one largest, broadly rhombic-ovate or compressed orbicular, 4-15 cm long, 5-15 cm wide, base broadly cordate to cuneate, margin usually irregularly coarsely serrate, apex obtuse or acute; cauline leaves: stipules green, leaflike, ovate, large, margin irregularly coarsely serrate; leaf blade pinnate, sometimes repeatedly lobed; terminal leaflet lanceolate or obovate-lanceolate, base cuneate, apex often acuminate or shortly so. Inflorescence terminal, lax. Flowers 1-1.7 cm in diameter; pedicel pubescent or hirtellous. Sepals ovate-triangular, apex acuminate; epicalyx segments lanceolate, minute, ca. 1/2 as long as sepals, abaxially pubescent and villous, apex acuminate, rarely 2-fid. Petals yellow, suborbicular, longer than sepals. Style terminal, twisted at joint ca. 1/4 way from apex; proximal section pilose; distal section deciduous at fruit maturity. Achene aggregate obovoid; fruiting receptacle hispidulous, hairs ca. 1 mm; achenes hirtellous; proximal section of style persistent, glabrous, apex hooked.

The chromosomal number of Geum aleppicum is 2n = 42 (Packer and Witkus, 1982; Dmitrieva, 1986; Iwatsubo and Naruhashi, 1993; Mesicek and Sojak, 1995).

Growing in forests, open places, grassy mountains slopes, river and stream banks, field; 200-3500 m.

The fruits of Geum aleppicum is used medicinally and as a source of oil.

Geum aleppicum, commonly called yellow avens or common avens is a flowering plant native to most of the temperate Northern Hemisphere, from eastern Europe across Asia and North America.

It is a herbaceous perennial plant growing to 1 m tall with pinnate leaves. The flowers are 2 cm diameter, yellow, with five to seven toothed petals.

There are two subspecies:

Geum aleppicum subsp. aleppicum. Europe and Asia. Geum aleppicum subsp. strictum. North America.