Mimosa grahamii A. Gray


Family: Fabaceae

Description: Spreading or decumbent shrub, 45.0 to 80.0 cm in height at matruity; the branches glabrous to pubescent, with spines usually somewhat hooked, but some may be straight; leaves 5.0 to 10.0 cm in length, the rachis prickly and with 4 to 8 pairs of pinnae, leaflets 8 to 15 pairs per pinna and 4.0 to 6.0 mm long; flowers white to pink, borne in globose axillary heads; fruits (legumes) linear, flat, not strongly constricted between the seeds, 2.0 to 3.5 cm in length, the margins entire or prickly; the leaves, flowers and fruits ranging from glabrous to pubescent.

Distribution: This uncommon species is confined to dry slopes and mesas in the southwest corner of New Mexico at 1,370-1,830 m (4,500-6,000 ft) in elevation. It is common in Arizona and Mexico where several varieties have been described.

Plants Seen or Cited: Carter Herbarium: Two collections from Hidalgo County, one from San Luis Mts. and one collection from Coronado National Forest. ARIZ: Total of 45 collections from AZ, with 25 collections of M. grahamii var. grahamii and 20 collections of M. grahamii var. lemmonii. Both varieties are now considered M. grahamii. NMSU: Total of 6 collections, all from Hidalgo County. Localities of four collections: one collection from Guadalupe Canyon, vicinity of Hadley Ranch; one collection Clanton Canyon: one collection San Luis Mts.; one collection Skeleton Canyon.

Comments: May be confused with several other species of Mimosa in southwest New Mexico, and it is not common, at the same time it is not rare.

Status: Uncommon, but not rare in New Mexico, and common in Arizona.

Important Literature:

Carter, Jack L. 1997. Trees and shrubs of New Mexico.

Kearney, T.H. and R.H. Peebles. 1951. Arizona flora.

Martin, W.C. and C.R. Hutchins. 1980. A flora of New Mexico.

Information Compiled By: Jack Carter, 1997