RUKAL ENGINEERING. 785 



sulphate aud uiayiiesiuiu suliihate, llius euipliasiziug tlie necessity for oauliou 

 ill the use of these waters for irrigation to prevent accumulations of allsali. 



In the Cretaceous area many wells have been sunJv, both deep and shallow, 

 from nearly all of which sufficient water for domestic use aud stock supply is 

 obtained. " The water from most of the springs and wells of moderate depth is 

 hard but of good quality for irrigation and fairly satisfactory for drinking aud 

 household use, but the water from the wells in certain localities, notably the im- 

 meiliate vicinity of Carrizozo. is too highly mineralized for drinking or house- 

 hold use and of doubtful character for irrigation." 



In the Carboniferous rocks and underlying sediments of the northern i)lateau 

 section of the basin, the agricultural problem is to obtain water for domestic 

 use aud live stock. " Some of the waters, especially those from shallow sources, 

 are fairly satisfactory for domestic use aud for drinking, but many are either 

 undesirable or wholly unfit for these uses. . . . 



" Tlie soils that are more or less suitable for agriculture can be grouped as 

 the re<l adobe soils, the gypseous soils, the more ordinary loam soils. . . . and 

 the sandy soils. The soils that produce more or less desert vegetation but are 

 practically worthies for agriculture can be grouped as the graA-elly and bowldery 

 deposits, the quartz sands of the dune areas, the gyiJSum sands, the alkali clays. 

 and the waste in the crevices of the lava beds." 



Analyses of samples of the soils of the area made at the station showed tbem 

 to be generally deficient in nitrogen. It is stated that the phosphoric acid con- 

 •tent compares fairly well with, that usually found in soils of average fertility. 

 The potash content was variable but was on the whole small as compared with 

 the content of soda aud other soluble salts. It is stated that the soils are in 

 poor tilth and neetl deep cultivation and green manuring. 



Analyses further showed large amounts of sulphates and calcium and only 

 very small amounts of carbonates or bicarbonates. In a few cases an excess 

 of chlorin over sodium was found, indicating the presence of either magnesium 

 chlorid or calcium chlorid. It was also found that the average amounts of 

 alkali within the capillary limits increased gradually witli decreasing depth of 

 ground water. " Wherever the water table is within about 12 ft. of the surface 

 the soil is liable to contain harmful amounts of alkali, and the nearer the sur- 

 fa<-e the ground water stands the greater is the d;inger from alkali. In all of 

 the samples taken in localities where the depth to water is less than 10 ft. the 

 alkali content was greater in the first foot of soil than farther down. . . . 

 Sodium chlorid and other alkalis are distributed in appreciable quantities over 

 much of that part of the interior gyp.seous plain where the water table is at 

 l)reseut too low to have any influence on surface conditions." 



The distribution of zones of vegetation was found to be influence<l by the 

 amounts of rainfall and flood waters and by the depths to ground water. It Is 

 stated that only about one acre in 1,000 is under irrigation in the basin. Surface 

 waters have been used to considerable extent with more or less success and the 

 areas pros])ectively available for irrigation with well waters are outlined as 

 follows: The shallow-water tracts in the Cretaceous area north of Three Rivers, 

 including land adjacent to Nogal Arroyo and near Carrizozo and Oscuro and the 

 surrounding country; the shallow-water tracts in the valleys of the Sierra 

 Blanca and Sacramento Mountains and adjacent foothills, especially in the 

 valley of Three Rivers; a belt on the east side of the basin extending from the 

 lower part of the younger lava befl to some distance south and southwest of 

 Dog Canyon, limited on the north, east, and south by the depth to water and on 

 the west by the alkali and gypsum in the soil : and a narrow belt on the west 

 side of the basin extending from the vicinity of Mound Springs to the meadow 



