Atriplex coulteri |
Atriplex linearis |
|
---|---|---|
Coulter's orach, Coulter's orache, Coulter's saltbush |
slenderleaf saltbush, thinleaf fourwing saltbush |
|
Habit | Herbs, perennial, sometimes flowering as an annual, spreading 0.7–10 dm, slightly woody at base. | Shrubs dioecious, erect, mainly 10–25 dm; branchlets slender, terete. |
Stems | frequently tinged with red, much branched, sparsely scurfy. |
|
Leaves | many, sessile or short petiolate; blade obovate, oblong, oblanceolate, or elliptic, (5–)7–20 × 1–3(–5) mm, base cuneate, margin entire, apex acute. |
sessile; blade narrowly linear-elliptic, 10–50 × 2–3 mm, firm, revolute, often acute apically. |
Staminate flowers | in glomerules in distal axils and short terminal spikes. |
in glomerules borne in slender interrupted mostly paniculate spikes. |
Pistillate flowers | in small axillary clusters. |
paniculate or in few-flowered axillary glomerules. |
Seeds | brown, 1.3–1.5 mm. |
|
Fruiting | bracteoles sessile or subsessile, broadly obovate, 2–3 mm and as broad or about as broad, united 1/2 of length, margin free, deeply and sharply dentate, narrowed at summit, faces smooth or sometimes tuberculate. |
bracteoles sessile or subsessile, lanceolate to ovate, 4–6 mm, about as wide, each bract with a pair of thin wings 3 mm broad or less, irregularly dentate or laciniate, free tips of bracts much exceeding the wings. |
2n | = 18. |
|
Atriplex coulteri |
Atriplex linearis |
|
Phenology | Flowering spring–fall. | Flowering spring–fall. |
Habitat | Somewhat alkaline or clay low places, valley grasslands, coastal sage scrub, coastal slopes | Saline deserts, with shadscale, Canotia, Yucca, Opuntia, Rhus, and Eriogonum |
Elevation | 0-500 m (0-1600 ft) | 0-800 m (0-2600 ft) |
Distribution |
CA
|
AZ; CA; nw Mexico (Baja California, Sonora)
|
Discussion | Of conservation concern. Atriplex coulteri is closely allied to the geographically disjunct A. fruticulosa, from which it is said to differ in the compressed, small (2.5–3 mm) versus thickened and larger (3–5 mm) bracts. Specimens of A. fruticulosa, including the type, examined by me have bracteoles compressed-thickened, but hardly “globoid” as stated in the key to the species by H. M. Hall and F. E. Clements (1923). Additional specimens borrowed from California might clarify the situation; otherwise the two species are sufficiently close as to be treated as a single entity. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Specimens of Atriplex canescens var. macilenta resemble A. linearis. The taxa have been placed together by some previous workers. Nevertheless, the stems of A. linearis are consistently more slender, the leaves proportionally narrower, and the bracts, though smaller, more closely simulate those of A. canescens. Its diploid nature signals a different evolutionary pathway than that for most of A. canescens, considered broadly. Narrow leaves occur within A. canescens, in the broad sense, sometimes with geographic correlation, sometimes not. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 4, p. 363. | FNA vol. 4, p. 381. |
Parent taxa | Chenopodiaceae > Atriplex > subg. Obione > sect. Obione > subsect. Arenariae | Chenopodiaceae > Atriplex > subg. Pterochiton |
Sibling taxa | ||
Synonyms | Obione coulteri | A. canescens subsp. linearis, A. canescens var. linearis |
Name authority | (Moquin-Tandon) D. Dietrich: Syn. Pl. 5: 537. (1852) | S. Watson: Proc. Amer. Acad. Arts 24: 72. (1889) |
Web links |