Vachellia californica - short shoots

Vachellia californica - stipular spines

Vachellia californica - trunk stipular spines

Vachellia californica - flower

Vachellia californica - flowers

Vachellia californica - habit

Vachellia californica - infloresence

Vachellia californica - habit

Vachellia californica - pubesence

Vachellia californica - stem

Vachellia californica - flower

Vachellia californica - petiolar gland


Vachellia californica (Brandegee) Seigler & Ebinger, Phytologia 87:  146.  2005.
syn. Acacia californica Brandegee, Proc. Calif. Acad. Sci. II.  3:  221.  1892.

Synonymy and types

Basionym:  Acacia californica Brandegee, Proc. Calif. Acad. Sci. II. 3: 221.  1892.  Acacia pringlei Rose subsp. californica (Brandegee) Lee, Seigler & Ebinger, Syst. Bot. 14: 99.  1989.  Acaciopsis californica (Brandegee) Britton & Rose, N. Amer. Fl. 23: 96.  1928. - TYPE:  MEXICO.  BAJA CALIFORNIA SUR:  La Palma, 31 Mar 1892, T. S. Brandegee s.n. [lectotype, designated by Lee et al. (1989):  UC].

Acacia sonorensis Rose, Contr. U. S. Nat. Herb. 8:31. 1903.  Acaciopsis sonorensis (Rose) Britton & Rose, N. Amer. Fl.  23: 95.  1928. - TYPE:  MEXICO.  SONORA:  near Guaymas, 5-11 Jun 1897, J. N. Rose 1247 (holotype:  US).

Formal description

Tree to 8 (12) m tall.  Bark dark gray to brown, shallowly furrowed.  Twigs dark purplish brown to dark gray, slightly flexuous, densely pubescent.  Short shoots commonly present above the stipular spines, to 8 mm long, covered with acuminate stipules and old leaf bases.  Leaves alternate, also commonly clustered on the short shoots, 4-10 mm long.  Stipular spines light to dark purplish brown, usually becoming light gray with age, symmetrical, terete, straight, thin, to 35 (50) x 1.5 (3.0) mm near the base, lightly pubescent throughout.  Petiole adaxially grooved, 4-10 mm long, densely pubescent; petiolar gland solitary, mostly located medially on the petiole, sessile, circular to elliptic, 0.4-1.8 mm long, apex depressed, glabrous to puberulent, sometimes absent.  Rachis absent.  Pinnae 1 pair per leaf, 15-35 mm long.  Petiolules 3-18 mm long.  Leaflets 2 to 3 pairs per pinna, subopposite to alternate, 5-18 mm between leaflets, ovate to obovate, terminal leaflet 11-25 x 6-18 mm, the lateral leaflets mostly smaller, densely pubescent on both surfaces, lateral veins obvious, 2 to 4 vein from the base, base oblique, margins densely ciliate, apex obtuse and usually mucronateInflorescence a loosely flowered elongated spike, 30-130 mm long, solitary or in clusters of 2 to 8 on the short shoots.  Peduncles 0-6 x 0.6-0.9 mm, densely puberulent.  Involucre usually 4-lobed, at the base of the pedunclepersistent.  Floral bracts spatulate, 0.7-1.2 mm long, puberulent, deciduous.  Flowers sessile, white to cream-colored; calyx 4-lobed, 0.7-1.4 mm long, glabrous and striated; corolla 4-lobed, 1.5-2.0 mm long, glabrous or nearly so; stamen filaments 2.5-4.0 mm long puberulent to glabrous, distince; ovary glabrous, on a stipe to 0.4 mm long.  Legumes dark reddish brown, straight to slightly curved, flattened, sometimes slightly constricted between the seeds, linear, 60-200 x 5-8 mm, coriaceous, reticulately striate, glabrous, eglandular, dehiscent; a chartaceous pericarpic strip lining each valvestipe to 12 mm long; apex acuminate and sometimes beaked.  Seeds uniseriate, no pulp, dark gray to dark brown, oblong, strongly flattened, 6.3-10.0 x 3.5-4.5 mm, smooth; pleurogram oblong to U-shaped, 1.1-2.0 mm across. Flowers in March to July. Chromosome number:  Not determined.


From Baja California Sur to Sinaloa and Sonora.

Additional info

The species Vachellia pringlei and V. californica, though disjunct, are closely related and specimens are sometimes difficult to place.  The species are usually easy to distinguish, however, by the presence of the dense pubescence on the smaller leaflets of V. californica.  In addition, petioles are consistently very short in V. californica (less than 10 mm), the leaflet margins are strongly ciliate, and most parts of the plant are densely pubescent.  The species are also similar in that a few specimens of V. californica tested positive for cyanide production if emulsin was used in the test (Lee et al. 1989).

Vachellia californica specimens from Baja California Sur differ in some respects from the material in Sonora and Sinaloa.  Though possibly the result of the small number of specimens available for study, the calyx and floral bracts of these two groups of specimens differ slightly in size.  In specimens from Baja California the calyx is 1.2-1.4 mm long, and the floral bracts are 1.0-1.2 mm long; Sinaloa and Sonora specimens have a smaller calyx (0.7-0.9 mm) and floral bracts (0.7-1.0 mm).  They are similar in all other characteristics.

Flowering time


Representative specimens


Baja California Sur: