Plants 3-15 dm, ± glaucous. Stems woody proximally, fleshy distally; articulations (joints) (2-)3-5(-10) × 1-4.5 mm. Leaves deciduous; blade 2-4 × 2-3 mm. Inflorescences 6-25 × 2.5-4 mm. Utricles enclosed by perianth. Seeds ca. 0.6 mm.

Flowering mid summer-late fall. Alkaline soils, mostly on raised sandy hummocks in salt playas and mud flats; 1000-1700 m; Ariz., Calif., Idaho, N.Mex., Nev., Oreg., Tex., Utah; Mexico.

A dominant shrub of salt playas and mudflats in the American Southwest, iodine bush is easily distinguished from great distances by the dark hue of its stems. The blackish-colored shrubs stand in stark contrast to surrounding vegetation and on close examination can be easily distinguished from the opposite-branched, but vegetatively similar members of Sarcocornia.

Common Name: iodinebush

Duration: Perennial

Nativity: Native

Lifeform: Shrub, Subshrub

Wetland Status: FACW

General: Succulent halophytic shrub, up to 2 m tall, from a woody base; stems fleshy, much branched, distinctly jointed and swollen, glabrous; internodes 5-20 mm.

Leaves: Tiny, scale-like, deciduous, and alternate at stem joints; blades triangular, 2-4 mm long and 2-3 mm wide.

Flowers: Tiny and inconspicuous, arranged in a small, dense, cylindric spike, 5-25 mm long; flowers sessile, spirally arranged, and subtended by deciduous fleshy peltate bracts; perianth 1-1.5 mm long, 4-5 lobed, green; flowers biexual.

Fruits: Utricles ovoid, composed of a single seed enclosed in the spongy fruiting calyx; seed erect, oblong, smooth, brown or reddish brown, less than 1 mm long.

Ecology: Found in alkaline and salty soils, especially at the margins of lakes, playas and streams, below 5,500 ft (1676 m); flowers April to September.

Distribution: OR to w TX; south to Baja Calif. Sonora, MEX.

Notes: A dominant shrub of salt playas and mudflats in the American Southwest, iodine bush is easily distinguished from great distances by the dark hue of its stems. The blackish-colored shrubs stand in stark contrast to surrounding vegetation and on close examination can be easily distinguished from the opposite-branched, but vegetatively similar members of the genus Sarcocornia. Also known as pickleweed, A. occidentalis appears leafless, with green fleshy jointed stems that look like a chain of small pickles. Traditionally placed in the goosefoot family (Chenopodiaceae), that entire family was recently lumped into Amaranthaceae.

Ethnobotany: Cahuilla, Yuma, and Pima used the seeds as a grain to make bread, porridge, and beverages. Seri of Mexico used it ceremonially.

Etymology: Allenrolfea named for Robert Allen Rolfe, an English botanist, orchid specialist, and the first curator of the orchid herbarium at the Kew Royal Botanic Gardens. Occidentalis from Latin occidens, or west, referring to this species' range across the western US.

Synonyms: Halostachys occidentalis

Editor: AHazelton 2015, AHazelton 2017