Cercocarpus ledifolius var. intricatus

(S. Watson) M. E. Jones

Bot. Gaz. 5: 154. 1880.

Common names: Littleleaf or dwarf mountain-mahogany
Endemic
Basionym: Cercocarpus intricatus S. Watson Proc. Amer. Acad. Arts 10: 346. 1875
Synonyms: C. arizonicus M. E. Jones C. intricatus var. villosus C. K. Schneider
Treatment appears in FNA Volume 9. Treatment on page 338. Mentioned on page 337.

Shrubs, 5–25 dm. Stems: long-shoot internodes 4–13 mm, sparsely villous, sericeous, or pilose, glabrescent, rarely glabrous; short shoots 2–10(–17) × 1–1.5 mm. Leaves: petiole 0.4–1.4(–2) mm; blade linear to linear-lanceolate, (3–)5–13(–18) × 1–1.5(–2) mm, margins strongly revolute (central groove 0.1–0.9 mm wide on abaxial surface in dried leaves), abaxial surface (largely obscured by leaf margins except on raised midvein where moderately, rarely densely hairy) usually villous, sometimes sericeous or hirsute, adaxial villous, sericeous, or hirsute, sometimes glabrescent, or glabrous. Flowers 1–5 per short shoot; hypanthial tubes strongly villous or sericeous; sepals 1–1.5 mm. Achenes 6–7 × 0.8–1.3 mm; fruit awns 3–4.5 cm, proximal setae 1.8–2.5 mm.


Phenology: Flowering late Mar–early Jun.
Habitat: Exposed, rocky slopes, ledges, bluffs with shallow soil, often cracks and crevices, alluvial slopes of limestone, dolomite, sandstone, or granite, with Artemisia, Coleogyne, Ephedra, Nolina, Purshia, pinyon and ponderosa pine, oaks, juniper woodlands
Elevation: 1000–2400(–3100) m

Distribution

V9 555-distribution-map.jpg

Ariz., Calif., Colo., Nev., N.Mex., Utah, Wyo.

Discussion

Variety intricatus is distinguished by rigid, moderately to strongly branched growth habit and stems densely clothed by linear, coriaceous, strongly revolute leaves with the abaxial surface exposed only along a narrow central groove. Long-shoot leaves are often larger than those of short shoots.

Variety intricatus is often treated as a distinct species; it is known to hybridize with var. intermontanus and var. ledifolius. Here, var. intricatus is restricted to plants with relatively small leaves. Variants with larger leaves, possible introgressants with the other taxa, are placed in var. ledifolius.

Selected References

None.

Lower Taxa

None.
James Henrickson +  and Brian D. Vanden Heuvel +
(S. Watson) M. E. Jones +
Cercocarpus intricatus +
Littleleaf or dwarf mountain-mahogany +
Ariz. +, Calif. +, Colo. +, Nev. +, N.Mex. +, Utah +  and Wyo. +
1000–2400(–3100) m +
Exposed, rocky slopes, ledges, bluffs with shallow soil, often cracks and crevices, alluvial slopes of limestone, dolomite, sandstone, or granite, with Artemisia, Coleogyne, Ephedra, Nolina, Purshia, pinyon and ponderosa pine, oaks, juniper woodlands +
Flowering late Mar–early Jun. +
C. arizonicus +  and C. intricatus var. villosus +
Cercocarpus ledifolius var. intricatus +
Cercocarpus ledifolius +
variety +