Acacia millefolia

Acacia millefolia

This species of Acacia differs from others by the following combination of characteristics: leaves bipinnate, flowers in spikes, plants unarmed or only slightly thorny, the pinnae in (4)6-10 pairs.
Isely (1973) records this species from Arizona and Mexico; Kearney and Peebles limit this general range slightly by stating that the species occurs in southern Arizona and northern Mexico. Wiggins (1964) indicate the species to be from Arizona, Sonora and Chihuahua. Britton and Rose (1928) give the type locality of this species [Senegalia millifolia (S. Wats.) Britt. & Rose] as the Hacienda San Jose in Chihuahua. This may be at the present San José de Babícora in western Chihuahua about 300 km south of the Mexico-US border for this was an important early collecting area, but without access to early literature and knowledge of the collector's itinerary the site must remain indefinite for the time being. Spellenberg et al. (1986) report the species for the first time in extreme southwestern New Mexico a few meters north of the Mexico-US border.
Ledges, desert grassland, open rocky slopes, foothills, 4,000-5,000 ft. (Isely 1973); generally igneous rock with sparse oak, juniper, and Mexican pinyon on rocky hills (Spellenberg & Repass 5371).
Important Literature

Kearney, T.H. 1942. The North American species of Sphaeralcea subgenus Eusphaeralcea. University of California Publications in Botany 19:1-127.

Britton, N.L, and J.N. Rose. 1928. Mimosaceae (continuatio). North American Flora 23(2): 77-136.

Estrada C., A.E., R. Spellenberg, and T. Lebgue. 1997. Flora vascular de la Laguna de Babícora, Chihuahua, México. Sida 17(4): 809-828.

González E., M.S. González E., Y. Herrera A. 1991. Flora de Durango. Listados Florísticos de México, IX. Instituto de Biología, Universidad Nacional Autónoma de México, México. 167 pp.

Isely, D. 1973. Leguminosae of the United States: I. Subfamily Mimosoideae. Mem. N. Y. Botanical Gard. 25(1): 1-150.

Martin, P.C., P. Jenkins, and others. 1990. Manuscript checklist of the plants of the Rio Mayo region in western Chihuahua and southern Sonora. 351 mss pages (no authors indicated).

Spellenberg, R., T. Lebgue, and R. Corral-Díaz. 1996. A specimen-based, annotated checklist of the vascular plants of Parque Nacional "Cascada de Basaseachi" and adjacent areas, Chihuahua, México. Listados Florísticos de México, XIII. Instituto de Biología, Universidad Nacional Autónoma de México, México. 72 pp.

Spellenberg, R., R. Worthington, P. Knight, & R. Fletcher. 1986. Additions to the flora of New Mexico. Sida 11(4):455-470.

Wiggins, I.L. 1964. Flora of the Sonoran Desert. Part II; pp. 189-1699 in: F. Shreve and I.L. Wiggins, Vegetation and Flora of the Sonoran Desert. Stanford Univ. Press, Standford. 2 vols, 1740 pp.

Information Compiled By
Richard Spellenberg 1998

For distribution maps and more information, visit Natural Heritage New Mexico