Kochia
J. Bot. (Schrader) 1800(1): 307. 1801.
Herbs and subshrubs, annual or perennial, glabrous or densely tomentose-sericeous. Stems erect, ascending, or prostrate, simple or branched, not jointed, not armed, not fleshy; branches alternate [proximal sometimes almost opposite]. Leaves alternate [rarely proximal almost opposite], sessile (sometimes narrowed into pseudopetiole); blade obovate-lanceolate, lanceolate, linear, or filiform, flat or semiterete, base truncate, margins entire, apex rounded. Inflorescences terminal, spicate or paniculately branched; flowers solitary or in 2–5-flowered clusters in axils of bracts; bracts leaflike. Flowers bisexual or pistillate, sessile; perianth segments 5, with horizontal, membranous wing [sometimes reduced to slightly winged tubercles] adaxially; stamens 5; stigmas 2–3. Fruiting structures: perianth covering utricles at maturity, utricles compressed-spheric or compressed-elliptic; pericarp free or nearly so, membranous. Seeds wedge-shaped; seed coat dull brown, slightly ribbed; embryo annular; perisperm copious. x = 9.
Distribution
North America, Eurasia, Africa, some species nearly worldwide (as introduced).
Discussion
Species 13–16 (3 in the flora).
Kochia occurs mostly in steppe, desert, and semidesert zones.
Selected References
Lower Taxa
Key
| 1 | Annual herbs; proximal cauline leaves usually (1-)3-5-veined, distinctly cuneate at base, sometimes narrowed into pseudopetiole [17a. Kochia sect. Semibassia] | Kochia scoparia |
| 1 | Subshrubs, stem bases woody; all leaves 1-veined (or vein obscure), sessile [17b. Kochia sect. Neokochia] | > 2 |
| 2 | Stems abundantly branched near base, distal parts simple or nearly so, finely white- tomentose or becoming glabrous; leaves usually overlapping | Kochia americana |
| 2 | Stems solitary or little-branched at base, branched throughout, grayish or brownish puberulent; leaves generally not overlapping | Kochia californica |