450 



FORESTRY AND IRRIGATION. 



November, 



lo to 30 feet of the surface, it grows to 

 large size. If the locality is protected 

 from heavy winds the tree grows erect, 

 but with a wide spread of branches. 

 If the locality is swept by strong 

 breezes it takes a wider spread or ar- 

 boreal form, the secondary trunks trail- 

 ing on the ground. If the prevailing 

 winds are heavy and frequent the stems 

 often grow along on the surface, one 

 tree forming what appears to be a great 

 mesquite thicket. 



be said that the sand covers the tree 

 rather than that the tree grows under 

 the sand. But this same form of mes- 

 quite growth is found near Wilcox, 

 Arizona, in the Sulphur vSpring and in 

 Aravaipa Valley, where there is no 

 sand-drift, but heavy winds. Here the 

 trunks grow entirely under the ground, 

 where the land is comparatively level, 

 only a slight mound and an abundance 

 of foliage indicating the hiding place of 

 the freakish Mesquite. This character- 



COPPICE REPRODUCTION, TWO YEARS' GROWTH, PINAL COUNTY, ARIZONA. 



This form of growth is of pronounced 

 type on the Gila River near Buckeye, 

 Arizona. Where the wind reaches the 

 velocity of a gale and sandstorms are 

 common the tree fortifies itself against 

 the relentless blasts by taking refuge 

 beneath the surface, as on the vSalton 

 desert in California, where the entire 

 trunk is covered, only the small shoots 

 appearing above the sand. Thus it 

 forms large sand-mounds, which are ex- 

 cavated by the woodman. Some of 

 these mounds, representing a single 

 plant, yield from one-quarter to three 

 cords of wood. In this locality it may 



istic is in part responsible for the origin 

 of the expression, " Dig for wood and 

 climb for water," in Arizona. 



The tree has other values than that 

 of fuel, fencing, and building purposes. 

 It is the manna of the desert, the bread- 

 tree of the southwest. Mesquite beans, 

 doubtless, have formed the staple food 

 product among the American Indians 

 of the arid regions during many ages. 

 It is the nutritious pods more than the 

 beans which are relished and used by 

 the Indians. The pods are ground in a 

 stone mortar or upon flat grinding stones 

 to the uniformity of a meal, the fiber of 



