420 MISC. PUBLICATION 423, U. S. DEPT. OF AGRICULTURE 



1. Prosopis juliflora (Swartz) DC, Prodr. 2: 447. 1825. 



Mimosa juliflora Swartz, Prodr. Veg. Ind. Occ. 85. 1788. 



Coconino County (Little Colorado Kiver, bottom of the Grand 

 Canyon) to Mohave County, southward to Cochise, Santa Cruz, 

 Pima, and Yuma Counties, 5,000 (exceptionally 6,000) feet or lower, 

 very # common, chiefly along streams and where the water table is 

 relatively high, April to August. Southern Kansas to southeastern 

 California and Mexico; southern South America. 



Two intergrading forms occur in Arizona: (1) var. velutina (Woot.) 

 Sarg. (P. velutina Woot.), the more common form, with pubescent 

 foliage and leaflets less than 15 mm. long; (2) var. glandulosa (Torr.) 

 Cockerell (P. glandulosa Torr.) with glabrous or glabrate foliage and 

 leaflets commonly more than 15 mm. long. Burkart apparently 

 excludes from P. juliflora the forms of the southwestern United States, 

 referring them/ at least as to var. velutina, to P. articulata S. Wats. 



Common mesquite, known also as honey mesquite. A large shrub 

 or small tree along watercourses, reaching a height of 9 m. (30 feet) or 

 more, and a trunk diameter of nearly 1 m. ; and scattered as a smaller 

 shrub on grasslands and lower mountain slopes, with much of the 

 trunk underground. It is reported that the roots sometimes pene- 

 trate to a depth of 60 feet. The foliage, and particularly the pods, 

 are eaten by livestock. The sapwood is yellow, the heavy reddish- 

 brown heartwoodhard and slow burning. With the exception of 

 Olneya, mesquite is the best firewood obtainable in the semidesert 

 region. Trees cut to the ground sprout again. The wood is used 

 for fence posts and the heartwood is said to take a fine polish. Mes- 

 quite increases rapidly on overgrazed grassland in southeastern Ari- 

 zona and is considered a serious range pest under such circumstances. 



This plant has been a mainstay of existence to the aborigines of the 

 Southwest. When cultivated crops failed, the Indians subsisted 

 mainly upon mesquite beans. Pinole, a meal made from the long 

 sweet pods, prepared in the form of cakes and in other ways, was a 

 staple food with the Pimas and still is eaten by them to some extent. 

 Fermented pinole was a favorite intoxicating drink. The gum which 

 exudes from the bark was used to make candy, to mend pottery, and 

 as a black dye. Several hundred pounds of mesquite gum are said 

 to be exported annually to Australia, for what purpose is not known. 

 The inner bark furnished the Indians material for basketry and coarse 

 fabrics, as well as medicine to treat a variety of disorders. Under 

 normal conditions large quantities of excellent honey are obtained 

 from the flowers of mesquite, which is rated by beemen as the most 

 valuable honey plant of the State. 



2. Prosopis odorata Torr. and Frem. in Frem., Exped, Rocky Mount. 



Rpt. 313. 1845. 



Strombocarpa pubescens A. Gray, PL Wright. 1: 60. 1852. 



Mohave County to Cochise, Pima, and (doubtless) Yuma Counties, 

 4,000 feet or (usually) lower, flood plains of streams, often in saline 

 soil, May (and doubtless later). Western Texas to southern Nevada, 

 southern California and northern Mexico. 



Fremont screwbean, also known as screwpod mesquite, and tornillo. 

 A shrub or small tree up to 6 m. (20 feet) high. Not generally so 

 abundant as the true mesquite, but the sweet pods were used by the 



