Ranunculus austro-oreganus |
Ranunculus marginatus |
|
|---|---|---|
|
southern Oregon buttercup |
margined buttercup |
|
| Roots | never tuberous. |
|
| Stems | erect or ascending, never rooting nodally, crisped-pilose, base not bulbous. |
erect, sparsely pilose. |
| Basal leaf blades | broadly rhombic to semicircular in outline, 3-parted, 2.8-4.3 × 3-5.5 cm, segments 3-lobed, ultimate segments lanceolate, margins entire or toothed, apex narrowly acute or acuminate. |
reniform to semicircular, undivided or shallowly 3-lobed, 2.5-5 × 3-7 cm, base truncate to nearly cordate, margins crenate or dentate, apex rounded or obtuse. |
| Flowers | receptacle glabrous; sepals reflexed 1 mm above base, 4-6 × 1.5-3 mm, densely pilose; petals 5, abaxially red, adaxially yellow, 10-12 × 4-6 mm. |
pedicellate; receptacle hispid; sepals 5, reflexed 1 mm from base, 3-5 × 1-2 mm, hispid; petals 5, 4-5 × 2-3.5 mm. |
| Heads | of achenes hemispheric, 4-7 × 7-10 mm; achenes 3.4-4.2 × 2.8-3.2 mm, sometimes basally pilose, margin forming narrow rib 0.1-0.2 mm wide; beak persistent, lance-subulate, straight or somewhat curved distally, 1.6-2.6 mm. |
of achenes hemispheric to globose, 4 × 6 mm; achenes 15-20 per head, 2.5-3 × 2-2.5 mm, faces covered with high sharp tubercles or low spines, glabrous, margin smooth; beak deltate, straight, 0.8-1 mm. |
Ranunculus austro-oreganus |
Ranunculus marginatus |
|
| Phenology | Flowering spring (May). | Flowering spring (Mar–May). |
| Habitat | Grassy hillsides | Roadsides |
| Elevation | 500 m [1600 ft] | 0-100 m [0-300 ft] |
| Distribution |
OR
|
AL; LA; TX; native to Europe [Introduced in North America] |
| Discussion | Of conservation concern. Ranunculus austro-oreganus is doubtfully distinct from R. occidentalis var. howellii. L. D. Benson (1954) described the stem as bulbous-based and similar to that of R. bulbosus, but a differentiated base is not evident in material I have seen (some of which was cited by Benson). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
A form of Ranunculus marginatus, with the fruits weakly tuberculate or almost smooth, similar to the smooth-fruited forms of R. sardous, is found in Europe; it is not known from North America. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
| Parent taxa | ||
| Sibling taxa | ||
| Name authority | L. D. Benson: Amer. Midl. Naturalist 52: 341. (1954) | d'Urville: Mém. Soc. Linn. Paris 1: 318. (1822) |
| Source | FNA vol. 3. | FNA vol. 3. |
| Web links |
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