226 



FORESTRY AND IRRIGATION 



May 



dicular "rim rock," that is such a char- 

 acteristic feature of the great west. 

 This lava floor has been cut and chis- 

 elled by the drippings of the ages until 

 we have to-day a whole system of 

 mesas corresponding to the same, well- 

 nigh perfect level. Above and beyond, 

 reaching to the upper confines of the 

 basin, rise other bodies of conglomer- 

 ate, capped by still other strata of rhy- 

 olite and basalt. 



The principal floral type is one of 

 evergreen, orchard-like woodland, and 

 of chapparal. This clothes all the bas- 

 in except the strictly north slopes. 

 These give rise to a deciduous oak 

 (Quercus gambelii) mixed with west- 

 ern yellow pine in an open stand. The 

 strictly evergreen type covers perhaps 

 90 per cent, or more of the area. The 

 trees and shrubs of general distribu- 

 tion are as follows, named in order of 

 importance from the economic stand- 

 point: Two species of iuniper, four of 

 oak, two of pine, mountain mahogany 

 (Ccrocarpus parvilfolius) , and Garrya 

 Wrightii. The junipers are Juniperus 

 pachyphloea, and Juniperus monosper- 

 ma, bearing the local names of juniper 

 and cedar, respectively. The oaks are 

 Quercus arizonica, Quercus hypoleuca, 

 Quercus gambelii, Quercus emoryi. 

 The first is locally known as scrub 

 oak ; the third as water oak, white oak ; 

 while the second and fourth are usu- 

 ally combined under the names of red 

 oak and black jack. The pines : Pinus 

 edulis, and Pinus ponderosa. The fore- 

 going are within each group placed in 

 order of relative abundance, which, 

 with the possible transposition of the 

 pines, is also the order of present rela- 

 tive economic value. 



There occur at least 26 other native 

 species in the basin, nearly all growing 

 along water-courses. The more prom- 

 ising of these for soil-binding on 

 stream banks and other purposes, are : 

 The poplars (Populus wislizeni, Po pu- 

 bis angustifolia), box elder, Mexican 

 walnut (Juglans rupestris), cherry 

 (Prunus salicifolia acutifolia) , willows 

 (Salix irrorata, and two others), lo- 

 cust (Robinio neomexicana) . Aside 

 from tree fruit and small fruit, three 



species have been introduced, viz. : 

 Populus acuminata, Sapindus margina- 

 tum, Sambucus glauca. The first-named 

 makes a phenomenal growth (5 to 6 

 feet annually) where water is at hand. 

 The soap-berry, next in order, shows 

 promise in spreading to arid soil. 



The chief use of such woody growth 

 as will thrive on this watershed is its 

 power for the conservation of soil and 

 water. The secondary use is almost 

 altogether for firewood and posts. 

 With fuel in the neighboring town of 

 Silver City worth $6.50 a cord, and 

 juniper posts growing scarce at 40 

 cents each, this is also important. 



The two species that deserve special 

 mention are the alligator juniper {Jun- 

 iperus pachyphloea) and Quercus ari- 

 zonica. Both are of wide and general 

 distribution, and maintain themselves 

 well under adverse conditions, each on 

 certain areas being the only woody 

 plant to survive. The oak grows upon 

 many steep slopes underlain by con- 

 glomerate, a soil cover that nature has 

 taken untold centuries of selection to 

 produce, and that man will probably 

 find impossible to improve. The juni- 

 per thrives alone on many a grassy 

 mesa, and reproduces vigorously on 

 cut-over areas under surroundings that 

 would kill any ordinary tree, root and 

 branch. The latter is true of the other 

 juniper as well, but this is limited in 

 distribution. Junipers are of slow 

 growth, and necessarily so in a climate 

 like this. Yet the past season (1905) 

 young growth has made an average of 

 about 15 inches, much more than any 

 other species on the same site. On 

 large areas the junipers are capable of 

 forming by far the best soil cover of 

 anything now growing, and it is at 

 least somewhat doubtful if anything 

 better can be made to grow in the fu- 

 ture. Moreover, they give the best 

 quality of wood of any species on the 

 watershed, both for fuel and posts. 

 But junipers are hard to produce ar- 

 tificially. The best present way to fa- 

 vor them appears to be to provide the 

 conditions best suited to the produc- 

 tion of natural young growth. But it 



