Cylindropuntia arbuscula

(Engelmann) F. M. Knuth in C. Backeberg and F. M. Knuth

in C. Backeberg and F. M. Knuth, Kaktus-ABC, 123. 1935.

Common names: Pencil cholla
Basionym: Opuntia arbuscula Engelmann Proc. Amer. Acad. Arts 3: 309. 1856
Treatment appears in FNA Volume 4. Treatment on page 106. Mentioned on page 104, 109.
Revision as of 22:22, 16 December 2019 by FNA>Volume Importer

Trees or shrubs, densely branched, 0.5–3 m. Stem segments green, sometimes purple tinged, 6–10.5 × 0.5–1.3 cm; tubercles narrowly elongate, appearing as wrinkles when dry, 1–2 cm; areoles circular, 2–3 mm in diam.; wool tan to brown, aging gray to black. Spines 0–2(–3) per areole, sparsely distributed along stem, usually deflexed, pale yellow or red-brown aging black, stout, the longest 0.8–3.5(–5) cm; sheaths loose fitting, yellowish brown. Glochids in adaxial tuft and marginal, encircling areole, pale yellow. Flowers: inner tepals green- or orange-bronze, spatulate, 17–20 mm, apiculate; filaments dark green-bronze; anthers yellow; style whitish basally to light orange apically; stigma lobes very pale green. Fruits green, becoming yellowish apically, sometimes tinged red to purplish at areoles, commonly sterile, then narrow, tuberculate, to 2.5 cm, fertile ones stipitate, obconic, 20–50 × 15–35 mm, fleshy, becoming smooth, spineless; umbilicus 3–4 mm deep; areoles 15–17(–34). Seeds pale yellow, angularly circular to oblong, thick, 3–5 mm diam., lumpy; girdle smooth, broad, not protruding. 2n = 66.


Phenology: Flowering spring (Apr–Jun).
Habitat: Sonoran Desert flats, bajadas, desert scrub
Elevation: 300-1000 m

Discussion

Cylindropuntia arbuscula forms hybrids with C. leptocaulis in south-central Arizona; those hybrids have narrow, obscurely tuberculate stems and reddish fruits nearly the size of those of C. arbuscula and chromosome number of 2n = 55. Hybrids between C. arbuscula and C. spinosior [= C. ×neoarbuscula (Griffiths) F. M. Knuth] have large green fruits, which often split open, and on stem segments distal areoles that usually bear three or four spines to 2.5 cm. Hybrids between C. arbuscula and C. versicolor [= C. ×vivipara (Rose) F. M. Knuth] have large green fruits, which often split open, and distal stem segment areoles that bear one or two spines to 1.5 cm.

Selected References

None.

Lower Taxa

None.
... more about "Cylindropuntia arbuscula"
Donald J. Pinkava +
(Engelmann) F. M. Knuth in C. Backeberg and F. M. Knuth +
Opuntia arbuscula +
Pencil cholla +
Ariz. +  and Mexico (Sonora). +
300-1000 m +
Sonoran Desert flats, bajadas, desert scrub +
Flowering spring (Apr–Jun). +
in C. Backeberg and F. M. Knuth, Kaktus-ABC, +
Opuntia sect. Cylindropuntia +
Cylindropuntia arbuscula +
Cylindropuntia +
species +