Lavatera trimestris

Linnaeus

Sp. Pl. 2: 692. 1753.

Common names: Annual or rose mallow
Introduced
Synonyms: Althaea trimestris (Linnaeus) Kuntze Stegia trimestris (Linnaeus) T. Luque & Devesa
Treatment appears in FNA Volume 6. Treatment on page 278. Mentioned on page 277.

Herbs, annual, usually 0.5–1.4 m. Stems sparsely hispid-hairy, hairs simple or few-rayed, glabrate in age. Leaves reduced distally; stipules narrowly triangular, 2–6 mm; petioles equaling blades proximally, 1–7 (–13) cm, reduced distally ca. 1/2 blade length; blade green, orbiculate, 2.5–7 (–12) cm, proximal leaves unlobed to shallowly 3–5-lobed or angled, distal leaves shallowly palmately 3–7-lobed, lobes triangular, margins crenate or dentate (serrate), apex acuminate or acute to obtuse, surfaces sparsely bristly to glabrous. Inflorescences solitary flowers, clustered towards stem tips, pedicellate. Pedicels 2 (–7) cm, elongating in fruit; involucellar bractlets connate halfway, subequal to or 3/4 length of calyx, lobes wide-deltate, 0.6–1 cm, distinctly enlarging in fruit, apex acute. Flowers showy; calyx divided ca. 1/2 its length, campanulate, 1–1.5 cm, enlarging in fruit, ± enclosing fruit, sparsely short stellate-hairy, lobes triangular to narrowly ovate, apex acute to acuminate; corolla 3–7 (–10) cm diam., petals rose-pink to white with darker rose veins, 2.5–3.5 (–7) cm, bases strongly overlapping (obscuring calyx between), apex blunt to rounded; staminal column puberulent; anthers on upper 3/4 of stamen column, pinkish; style ca. 12+-branched. Mericarps ca. 12+, 3.3–3.7 mm, ridged, covered and obscured by disclike expansion of central axis, glabrous, transverse-reticulately veined on back. 2n = 14.


Phenology: Flowering Jun–Oct.
Habitat: Disturbed habitats
Elevation: 0–600 m

Distribution

V6 507-distribution-map.jpg

Introduced; Calif., Conn., Mo., Pa., Tex., Vt., s Europe, w Asia

Discussion

Lavatera trimestris, the type species of the genus, is occasionally cultivated as a garden ornamental; it rarely escapes or naturalizes. Most records are of plants that did not persist. It is easily distinguished from other commonly cultivated mallows by the disclike expansion of the central axis of the fruit above the mericarps.

Selected References

None.

Lower Taxa

None.

"/2" is not declared as a valid unit of measurement for this property.

... more about "Lavatera trimestris"
indehiscent +
hairy +  and glabrous +
Steven R. Hill +
Linnaeus +
overlapping +
rounded +  and wide-cuneate unlobed or palmately 3-7-lobed +
7 cm70 mm <br />0.07 m <br /> (12 cm120 mm <br />0.12 m <br />) +
orbiculate +
reduced +
2.5 cm25 mm <br />0.025 m <br /> (7 cm70 mm <br />0.07 m <br />) +
narrower +
cupuliform +
stellate-hairy +
campanulate +  and divided +
enlarging +
1 cm10 mm <br />0.01 m <br /> (1.5 cm15 mm <br />0.015 m <br />) +
indehiscent +  and loculicidal +
Annual or rose mallow +
purple +, white +  and rose-pink +
3 cm30 mm <br />0.03 m <br /> (7 cm70 mm <br />0.07 m <br />) +
Calif. +, Conn. +, Mo. +, Pa. +, Tex. +, Vt. +, s Europe +  and w Asia +
rounded +
0–600 m +
sparse;copious +
pistillate +  and staminate +
unisexual +  and bisexual +
flattened-globose +  and not inflated +
Disturbed habitats +
few-rayed +  and simple +
axillary +  and terminal +
tough-fibrous +
connate +  and distinct +
simple +, stipulate +, sessile +, subsessile +  and petiolate +
distichous +  and alternate +
reduced +
triangular +  and narrowly ovate +
enlarging +
entire +  and serrate +
dentate;crenate +
Brown (?) +, Tan (?) +  and Drying (?) +
0.33 cm3.3 mm <br />0.0033 m <br /> (0.37 cm3.7 mm <br />0.0037 m <br />) +
[9-]12-22[-40]-carpellate +
2 cm20 mm <br />0.02 m <br /> (7 cm70 mm <br />0.07 m <br />) +
elongating +
2 cm20 mm <br />0.02 m <br /> (?) +
3.5 cm35 mm <br />0.035 m <br /> (7 cm70 mm <br />0.07 m <br />) +
adnate +  and distinct +
2.5 cm25 mm <br />0.025 m <br /> (3.5 cm35 mm <br />0.035 m <br />) +
Flowering Jun–Oct. +
reniform +
persistent +
Introduced +
sessile +  and subsessile +
filiform +  and decurrent +
1-2 times number of carpels +
early-deciduous +
0.2 cm2 mm <br />0.002 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
12+-branched +
disc--shaped +, conic +  and swollen +
sparsely bristly +  and glabrous +
Althaea trimestris +  and Stegia trimestris +
Lavatera trimestris +
Lavatera +
species +
darker rose +
keeled +  and ridged +
glabrate +  and stellate-hairy +
monoecious +, dioecious +  and hermaphroditic +