Lomatium ochocense
Gerald D. Carr

Flora of Oregon

Plants acaulescent.

Roots globose tubers with an irregularly thickened, or elongate and slender upper portion 2–4 cm.

caudices simple or 2–3-branched; basal leaf sheaths from previous years absent or weathering into a thatch of a few, loose fibers or chartaceous scales at base of pseudoscape.

Stems absent; pseudoscapes 2–4 cm, subterranean.

Basal leaves glabrous and glaucous, thick or somewhat succulent; primary leaflets pinnate, 1–3 secondary leaflet pairs along each rachis, laterals half central primary in length; secondaries pinnatifid (4–7-lobed); tertiaries absent; ultimate apical lobes obovate or oblong, 2–6 × 2–3.5 mm, tips subacute, obtuse, or rounded, mucronulate.

Cauline leaves 0.

Inflorescences peduncles 1–2, spreading or ascending, 4–6 cm, glabrous; involucral bracts 0; rays 2–6, 0.4–1 cm, glabrous; involucel bractlets 4–8, elliptic or lanceolate, 2–4 × 0.4–1 mm, margins scarious; umbellets 10–15-flowered; pedicels 2–4 mm.

Flowers petals yellow; anthers ochroleucous or yellow.

Fruits elliptic, 5–8 mm, glabrous; body 2–3.5 mm wide; wings 0.5–1 mm, thin; vittae 2–3 in intervals, 4 on commissure.

Gravelly or rocky outcrops or slopes in scablands, on basalt-derived substrates. Flowering Apr–May. 1300–1500 m. Lava. Native. Endemic to Oregon.

More collections from Oregon are needed to determine the range of variability of the morphology of this taxon.

Photo images

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Herbarium specimens

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