Common Name: BUCKWHEAT FAMILY
Habit: Annual to shrub [tree]. Stem: nodes swollen or not. Leaf: simple, basal or cauline, generally alternate; ocreae present or 0, generally scarious, persistent or not. Inflorescence: flower clusters in axillary to terminal cyme-, panicle-, raceme-, spike-, umbel- or head-like arrangements, entire inflorescence or main inflorescence branches generally subtended by bracts ("inflorescence bracts"); peduncles present or 0; flower clusters in Eriogoneae-Eriogonoideae subtended by involucre of >= 1 free or +- fused, sometimes awn-tipped bracts ("involucre bracts") or, in Polygonoideae and rarely in Eriogonoideae, not (if bracts completely fused, involucre "tubular"); pedicels in Eriogoneae each often subtended by 2 free, transparent, linear bractlets or in Polygonoideae all subtended by 2+ fused, membranous, wide bractlets. Flower: generally bisexual, small, 1--200 per node; perianth parts 2--6, generally in 2 whorls, free or basally fused, generally petal-like, often +- concave adaxially, often darker at midvein, often turning +- red or +- brown in age; stamens [1]3 or 6--9 in 2 whorls; ovary superior, 1-chambered, ovule 1, styles 1--3. Fruit: achenes, included in or exserted from perianth, generally 3-angled, ovoid or elliptic, generally glabrous.
Genera In Family: 48 genera, +- 1200 species: worldwide, especially northern temperate; some cultivated for food (Coccoloba, sea-grape; Fagopyrum, Rheum, Rumex) or ornamental (Antigonon, lovechain; Coccoloba; Muehlenbeckia; Persicaria; Polygonum), a few timbered (Coccoloba; Triplaris). Several (Emex; Fallopia; Persicaria; Polygonum; Rumex) are weeds. Note: Treatment of genera in Eriogonoideae based on monographic work of James L. Reveal. Involucre number throughout is number (1--many) per ultimate grouping, at tips of ultimate branches; flower number is per flower cluster or involucre, unless otherwise stated. Fagopyrum esculentum Moench not naturalized, considered an historical waif (or garden weed +- presently), therefore not treated.
eFlora Treatment Author: Mihai Costea, except as noted
Scientific Editor: Thomas J. Rosatti, Bruce G. Baldwin.

Common Name: SPINEFLOWER
Habit: Annual [perennial herb], generally hairy. Stem: branches basal or from erect stem, prostrate or decumbent to ascending. Leaf: all basal or basal and cauline, alternate except for bracts, awnless; ocreae 0. Inflorescence: cyme-like, open to +- congested; axes generally 3 from plant base or proximalmost branching node of erect stem, equally or unequally forked; bracts opposite or whorled, entire, generally in whorl of 3 at proximalmost branching node, not distinguishable from basal leaves in plants branched from base, distal generally opposite, proximal leaf-like or some or all scale-like to linear, needle-like, awnless or distal often all awned; involucres sessile, generally solitary at axis forks, distally in loose to dense clusters; involucre tubular, 3--6-ribbed, lobes 3, 5, or 6, equally or unequally awned, awns straight or hooked; involucres at forks often differing from those in clusters. Flower: 1(2) per involucre; pedicel short, included in involucre; perianth glabrous or hairy, white, yellow, pink, maroon, or purple, sometimes 2-colored, lobes (5)6, entire, minutely toothed, or fringed, tip acute, rounded, notched, or 2-lobed; stamens generally 3, 6, or 9. Fruit: generally brown or black, generally ellipsoid, glabrous; embryo straight or curved.
Etymology: (Greek: divided flower, for perianth lobes) Note: Involucre length measurements include lobes and awns unless otherwise specified. Chorizanthe minutiflora and C. aphanantha newly described, added; C. eastwoodiae segregated from C. angustifolia.
eFlora Treatment Author: James L. Reveal, Thomas J. Rosatti, David Gowen & David J. Keil
Reference: Morgan et al. 2014 Phytoneuron 2014-63:1--9; Nelson et al. 2018 Madroño 65:184--191; Gowen & Johnson 2020 Phytotaxa 455(1):1--8.