Lavatera olbia

Linnaeus

Sp. Pl. 2: 690. 1753.

Common names: Tree lavatera or mallow
Introduced
Synonyms: Althaea olbia (Linnaeus) Kuntze Lavatera hispida Desfontaines
Treatment appears in FNA Volume 6. Treatment on page 277. Mentioned on page 278.

Subshrubs or shrubs, usually 1–2 m. Stems woody at base, bristly-hairy, young stems tomentose, infrequently glabrescent. Leaves reduced distally; stipules narrowly lanceolate, 2–4 mm; petioles to 10 cm in proximal leaves, reduced distally to 1/4 blade length; blade green, to 15 cm, surfaces densely stellate-tomentose, proximal blades broadly to narrowly ovate, 3–5-lobed, lobes lanceolate to ovate, margins crenate-dentate to nearly entire, apex acute to rounded, distal blades oblong-ovate to lanceolate, often slightly 3-lobed and subhastate. Inflorescences solitary flowers or congested racemelike distally, subsessile. Pedicels 0.2–0.7 cm, not elongating in fruit; involucellar bractlets connate halfway, subequal to calyx, lobes wide-ovate, apex acuminate. Flowers showy; calyx divided halfway, campanulate, ciliate, hispid-hairy, lobes abruptly acuminate, ± enclosing fruit; corolla 4–6 cm diam., petals pink to purple-violet, veins darker rose, 2–3 cm, bases not overlapping (calyx visible between), apex shallowly notched; staminal column glabrous; anthers on upper 3/4 of stamen column, pink to yellowish; style 17–19-branched (same number as locules). Mericarps 17–19, tomentose or hispid, sides sometimes glabrate. 2n = 42.


Phenology: Flowering Jun–Aug(–Oct).
Habitat: Disturbed habitats
Elevation: 0–100 m

Distribution

V6 505-distribution-map.jpg

Introduced; Calif., sw Europe.

Discussion

Lavatera olbia is widely cultivated as a garden ornamental and along highway medians; it only rarely escapes or naturalizes, but a few apparent escapes have been found in Monterey, Orange, and San Francisco counties. Lavatera olbia and L. thuringiaca hybridize to produce the occasionally cultivated hybrid Lavatera ×clementii Cheek.

Selected References

None.

Lower Taxa

None.