Rosa woodsii subsp. arizonica

(Rydberg) W. H. Lewis & Ertter

Novon 17: 350. 2007.

Common names: Arizona rose
Illustrated
Basionym: Rosa arizonica Rydberg in N. L. Britton et al., N. Amer. Fl. 22: 516. 1918
Synonyms: R. granulifera Rydberg R. woodsii var. arizonica (Rydberg) W. H. Lewis
Treatment appears in FNA Volume 9. Treatment on page 108. Mentioned on page 106.

Shrubs, 10–25+ dm, usually forming thickets. Stems openly branched; prickles usually present on distal stems and branches, infrastipular strongly curved or hooked, sometimes introrse, stout, sometimes flattened, 2–8 mm, internodal sparse or absent. Terminal leaflets usually elliptic, rarely cordate or narrowly ovate, 10–30 mm. Inflorescences 1 or 2(–4)-flowered. Sepals: abaxial surfaces usually stipitate-glandular, sometimes eglandular. 2n = 14.


Phenology: Flowering May–Jun.
Habitat: Sandy soil of oak, juniper, and pine forests, alluvial flats, brushy hillsides, sandstone cliff bases, sunny road banks
Elevation: 1300–2400 m

Distribution

V9 158-distribution-map.jpg

Ariz., Nev., N.Mex., Utah, Mexico (Chihuahua).

Discussion

Subspecies arizonica occurs primarily along streams in forested areas of Arizona, southern Nevada (Spring Mountains), northwestern New Mexico, and southern Utah with extensions into mountainous regions. Tall open habit, strongly curved prickles, and stipitate-glandular sepals are diagnostic, although not always present in combination. Plants with relatively few or no prickles, endemic to the West Fork of Oak Creek Canyon in Coconino County, Arizona, are var. ertterae W. H. Lewis, the Ertter rose; conservation attention to this variety is warranted. The remainder of the subspecies is var. arizonica.

Selected References

None.

Lower Taxa

None.
Walter H. Lewis +, Barbara Ertter +  and Anne Bruneau +
(Rydberg) W. H. Lewis & Ertter +
Rosa arizonica +
Arizona rose +
Ariz. +, Nev. +, N.Mex. +, Utah +  and Mexico (Chihuahua). +
1300–2400 m +
Sandy soil of oak, juniper, and pine forests, alluvial flats, brushy hillsides, sandstone cliff bases, sunny road banks +
Flowering May–Jun. +
Illustrated +
R. granulifera +  and R. woodsii var. arizonica +
Rosa woodsii subsp. arizonica +
Rosa woodsii +
subspecies +