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 the species are tropical or sub-tropical. Within our borders, they grow in the creosote-bush belt of our southwestern desert region. Standley, in The Shrubs and Trees of Mexico, refers all the species of strombocarpa to the genus prosopis."

Mr. J. J. Thornber, Botanist, Arizona Agricultural Experiment Station, Tucson, Arizona, says he has seen the beans so abundant under the tree "as to cover the ground everywhere for a considerable area as much as one inch or two inches in depth," and that a good-sized tree yields anywhere from fifty to one hundred pounds of beans. A space ten feet square would hold thirteen bushels or more than two hundred and fifty pounds if the beans were two inches deep.

Mr. Robert C. Forbes, Director of this same station, wrote a bulletin (No. 13) urging the use of mesquite as a crop because of the two qualities of good food and value of productivity of the tree.