5. Malva sylvestris L. (high mallow)
M. sylvestris var. mauritiana (L.) Boiss.
Pl. 453 e, f;
Map 2060
Plants biennial
(perennial in warmer climates). Stems 40–150 cm long, erect or ascending,
glabrous or sparsely pubescent with stellate hairs. Stipules 3–8 mm long,
linear to ovate-triangular. Leaf blades 2–8 cm long, flat or somewhat crisped
or curled toward the margins, circular to broadly kidney-shaped in outline,
unlobed to 3–7-angled or broadly and shallowly lobed (much less than 1/2 way to
the base), the margins finely scalloped or toothed, the surfaces glabrous or
sparsely pubescent with mostly simple or fasciculate hairs, also usually with
stellate hairs at the base. Flowers in axillary clusters, long-stalked, the
bractlets subtending the calyx oblong-ovate to narrowly obovate, glabrous or
sparsely hairy, except along the margins. Calyces 5–6 mm long at flowering,
expanding to 9 mm long at fruiting, initially cup-shaped, but becoming slightly
enlarged and somewhat flattened horizontally at fruiting, with a distinct
network of veins toward the base, the outer surface pubescent with mostly
stellate hairs, the marginal hairs stellate and fasciculate, all less than 0.5
mm long. Petals 1.5–2.5 cm long, reddish purple. Fruits 2.0–2.5 mm long, flat
on the dorsal surface, glabrous or somewhat hairy, moderately to strongly
wrinkled or with a reticulate pattern of thickenings, angled at the junction
between the dorsal and lateral surfaces, the sides thin and papery, with a
radiating network of thickened veins. Seeds 1.5–2.2 mm long. 2n=42.
May–July.
Introduced,
widely scattered in Missouri (native of Europe, Asia; escaped sporadically in
North America). Roadsides, railroads, and open disturbed areas.
Malva
sylvestris is cultivated
as an ornamental in gardens and occasionally escapes from cultivation.