Althaea cannabina

Linnaeus
Sp. Pl. 2: 686. 1753.
Common names: Hemp-leaved marshmallow
Introduced
Synonyms: Althaea kotschyi Boissier A. narbonnensis Pourret ex Cavanilles
Treatment appears in FNA Volume 6. Treatment on page 232. Mentioned on page 231.

Herbs perennial, (0.5–)1–2 m. Stems erect, clumped, branched distally, canescent, hairs stellate. Leaves: stipules mostly persistent, narrowly linear, simple or 3-fid, 2–8 mm; petiole as long as blade in proximal leaves, greatly reduced in distal leaves; blades of proximal leaves deltate-ovate, 3–5-palmately lobed or divided ± to base, 3–12 × 2–16 cm, lobes oblong to lanceolate, middle lobe longest, margins deeply dentate to serrate, surfaces stellate-hairy, blades of upper leaves similar but narrower, 3–5-palmately lobed or divided, 1–4.5 × 0.5–6 cm, base cuneate, margins serrate, apex acuminate. Inflorescences solitary flowers, usually long-pedunculate (1–15 cm) or peduncle 2–3-flowered apically; bracts 2, linear, 2 mm. Pedicels 0.5–16 cm; involucellar bractlets 7–9, erect, lanceolate, 3–7 mm, slightly accrescent, 1/2+ as long as calyx, stellate-tomentose. Flowers: calyx 5–7(–10) mm, lobes ovate, 2 times as long as tube, margins entire, apex obtuse, acuminate, or apiculate, stellate-tomentose; petals pink to pink-purple, 10–23 × 5–12 mm, 2 times as long as calyx, apex obtuse or notched; staminal column 0.5–6 mm, glabrous or sparsely clavate-hairy; anthers in upper 1/2, purplish to purplish brown; stigmas 12–16. Fruits somewhat longer than calyx and not concealed, 7 mm diam.; mericarps 12–16, brown, unwinged, reniform, 2.5–4 × 2–3.5 mm, striate with ribs radiating from rugose central area, back herringbone-veined, glabrous. Seeds brown, reniform, 3 mm, glabrous. 2n = 84.


Phenology: Flowering summer.
Habitat: Disturbed, usually moist areas
Elevation: 0–200 m

Distribution

V6 414-distribution-map.jpg

Introduced; D.C., Europe, Asia (nw Iran, s Russia, Turkey, Turkistan), widespread.

Discussion

Althaea cannabina is occasionally cultivated as an ornamental, and rarely escapes or naturalizes.

Selected References

None.

Lower Taxa

None.