Johanneshowellia

Reveal

Brittonia 56: 299. 2004.

Common names: Howell’s-buckwheat
Etymology: for John Thomas Howell, 1903–1994, California botanist and Eriogonum scholar
Basionym: Puberula Rydberg Fl. Rocky Mts., 211. 1917
Treatment appears in FNA Volume 5. Treatment on page 443. Mentioned on page 219, 220.
Revision as of 22:38, 16 December 2019 by FNA>Volume Importer

Herbs, annual; taproot slender. Stems arising directly from the root, weakly erect to spreading, solid, not fistulose or disarticulating into ringlike segments, silky-puberulent. Leaves usually quickly deciduous, basal, rosulate; petiole present; blade obovate to rounded or somewhat reniform, margins entire. Inflorescences terminal, cymose; branches dichotomous or trichotomous at proximal node, otherwise dichotomous, not brittle or disarticulating into segments, round, silky-puberulent; bracts 3, connate proximally, triangular or linear to narrowly lanceolate, scalelike or somewhat leaflike, not awned, glabrous to puberulent. Peduncles absent. Involucral bracts obscure, in tight spiral of (3–)4(–7) distinct, oblanceolate to obovate lobes, bractlike, not awned. Flowers 4–7 per involucral cluster; perianth white or pale yellowish to rose or red, broadly campanulate when open, narrowly urceolate when closed, smooth or minutely pustulose abaxially, glabrous; tepals 6, connate 1/4 their length, monomorphic or slightly dimorphic, entire apically; stamens 9; filaments basally adnate, glabrous; anthers white to pale pink, oblong. Achenes included, light brown, not winged, 3-gonous, glabrous. Seeds: embryo curved.

Distribution

w United States.

Discussion

Species 2 (2 in the flora).

With recognition of Johanneshowellia, all members of Eriogonum have their involucral bracts fused into a distinct, turbinate to campanulate or hemispheric, tubular structure. In Johanneshowellia, the four to seven, distinct, involucral bracts are arranged in a tight spiral. Each 0.5–1.2 mm, awnless, entire to deeply lobed bract subtends a flower-bearing pedicel. These involucral bracts are themselves usually obscured by inflorescence bracts that subtend each node. As a result, care must be taken to observe the true nature of the involucral complex. The genus is allied with Eriogonum subg. Oregonium.

Selected References

None.

Key

1 Perianths minutely pustulose basally and along midribs, 1.5-2 mm in fruit; outer tepals narrowly ovate, slightly auriculate basally with slightly undulate-crisped margins in fruit; plants grayish to greenish, mostly densely silky-puberulent Johanneshowellia puberula
1 Perianths smooth, 2-2.5 mm in fruit; tepals lanceolate, not auriculate basally, margins entire; plants reddish, thinly silky-puberulent Johanneshowellia crateriorum