Page authors: Don Knoke, David Giblin
Allium macrum
rock onion

Distribution: Occurring east of the Cascades crest in Washington; central Washington to southern Oregon and southwestern Idaho.

Habitat: Lithosol and barren, gravelly soils in the shrub-steppe.

Flowers: April-May

Origin: Native

Conservation Status: Not of concern


Scapose perennials from ovoid bulbs, usually solitary, outer coats brownish, without a network pattern.


Leaves 2, much longer than the scape, concave-convex or flattened, narrow, tardily deciduous; scape nearly terete, somewhat ridged, up to 1 dm. tall.


Umbel several- to many-flowered, pedicels 1-3 times as long as the tepals; tepals 5-7 mm. long, lanceolate, pointed, white or pinkish with greenish or reddish midribs; stamens 6, slightly exerted; anthers dark, purplish-brown or reddish.


Capsule 3-celled and 3-lobed, without a crest.

Accepted Name:
Allium macrum S. Watson
Publication: Proc. Amer. Acad. Arts. 14: 233. 1879.

Synonyms & Misapplications:
(none provided)
Additional Resources:

PNW Herbaria: Specimen records of Allium macrum in the Consortium of Pacific Northwest Herbaria database.

WA Flora Checklist: Allium macrum checklist entry.

E-Flora BC: Allium macrum atlas page.

CalPhotos: Allium macrum photos.

USDA Plants: Allium macrum information.

29 photographs:
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