Sanborn's Onion

Bulbs 1–3, not clustered on stout, primary rhizome, ovoid, 1–2.5(–3) × 1.2–2 cm; outer coats enclosing 1 or more bulbs, dark reddish brown, chartaceous, lacking cellular reticulation or cells arranged in 2–3 rows distal to roots, ± quadrate, without fibers; inner coats light brown or white, cells obscurely quadrate. Leaves persistent, withering from tip by anthesis, 1, basally sheathing, sheath never extending much above soil level; blade solid, terete, 30–45 cm × 2–4 mm. Scape persistent, solitary, erect, ± solid, terete, 18–60 cm × 2–3 mm. Umbel persistent, erect, compact, 18–190-flowered, hemispheric to globose, bulbils unknown; spathe bracts persistent, 4, 3-veined, ovate, ± equal, apex long-acuminate. Flowers campanulate, 5–9 mm; tepals erect, white to pink with darker midveins, unequal, becoming papery in fruit, margins entire or irregular to erose, apex acute or acuminate to long-acuminate; outer tepals lanceolate to ovate, reflexed at tip; inner 1/4–1/3 longer than outer, ovate to broadly ovate; stamens exserted; anthers yellow or purple; pollen yellow or white; ovary crested; processes 6, prominent, erect, ± triangular, margins entire; style linear, equaling stamens; stigma capitate, obscurely to distinctly 3-lobed, lobes erect or spreading, ± stout; pedicel 8–22 mm. Seed coat dull; cells minutely roughened.

Allium sanbornii is a North American species of wild onion known by the common name Sanborn's onion. It is native to northern California and southwestern Oregon. It grows in the serpentine soils of the southern Cascade Range and northern Sierra Nevada foothills.

Allium sanbornii produces a reddish-brown bulb up to about 2.5 cm (1 in) long. Scape up to 60 cm (24 in) long, bearing a single cylindrical leaf which is about the same length. The umbel contains as many as 150 small flowers, each with tepals less than a centimeter long, pink to white with darker red midveins. Anthers are yellow or purple; pollen yellow or white.

Varieties Allium sanbornii var. congdonii Jeps. - from Nevada County to Mariposa County Allium sanbornii var. sanbornii - from Shasta County to Mariposa County in California; Jackson + Josephine Counties in Oregon formerly included Allium sanbornii var. jepsonii Ownbey & Aase ex Traub, now called Allium jepsonii (Ownbey & Aase ex Traub) S.S.Denison & McNeal Allium sanbornii var. tuolumnense Ownbey & Aase ex Traub, now called Allium tuolumnense (Ownbey & Aase ex Traub) S.S.Denison & McNeal