120 GUIDEBOOK OF THE WESTERN UNITED STATES 
in the Big Bend region, causing a lake or series of lakes extending up 
the valley to the mountains at El] Paso. In these waters were depos- 
ited a thick mass of fine-grained sediments, in large part of flesh color, 
orange-brown, and pale grayish green. Some beds are sandy, and 
thin sandstone layers are included; where these deposits are near the 
mountain slopes much coarse material is present. The lake beds were 
capped by stream deposits, which now fill many old gaps and extend 
over moderately high divides. North of Fort Bliss holes 2,300 feet 
deep have failed to reach the base of the valley fill. 
The lacustrine condition in the Rio Grande Basin was terminated 
by the deepening of the outlet; this finally tapped off the water, and 
then, as canyons were cut through the ridges, a deep valley was devel- 
oped. As the process continued, the side streams and arroyos cut 
deeply into the alluvial capping and the underlying lake deposits, and 
in the main valley terraces and a wide alluvial flat were developed. 
MeNary, formerly known as Nulo, has developed into a small town 
for local trade in the irrigated district along the Rio Grande. This 
preNazy: valley, with rich bottom-land soils, mild climate, wide 
ee eos areas of level surface, and a large water supply from 
Population 50.* +‘ the river now controlled by the Elephant Butte Reser- 
sais Orleans 1,131 voir, has developed rapidly in recent years. Much of 
mues. 
the land from McNary to El Paso is under irrigation 
and is yielding large crops of cotton, alfalfa’? and other forage plants, 
grain, fruits, and vegetables. The railroad passes near or through 
cultivated fields for the entire route, in striking contrast to the sand 
hills and barren lands of the area above the ditches. The alfalfa 
fields are usually of a rich green color, which becomes shaded with 
the lavender of the sweet-smelling blossoms when the plant is left to 
continue its growth for the development of seed. In 1929 the irri- 
gated area in Hudspeth County was about 14,000 acres and in El 
87 Alfalfa (lucern in Europe) Ser fone 1 Boake Gate highs Guia 
been cultivated as forage, for historians 
record its introduction into Greece from 
Besides being highly nutritive and pala- 
table, alfalfa, when well rooted, is of 
rank growth, long lived, and hardy. 
Persia as early as the fifth century be- 
fore Christ. Its cultivation was at- 
regions, for it does not require a moist 
climate and does not suffer from ex- 
treme heat or from relatively severe 
cold. It thrives best under irrigation, 
an occasional g being n 
for its growth. It has been found by 
the Arizona Agricult, Experiment 
Some fields are 25 years old, but on 
most soils the best yields are obtained 
in the third to seventh years. The 
roots range from 6 to 15 feet in length. 
Though alfalfa fields can be started in 
some places with a pound of seed (about 
220,000 seeds) to the acre, about 15 
| pounds is used on irrigated lands. In 
places alfalfa is cut three to five times 
& year and therefore produces a larger 
yield than any other forage plant in the 
western United States. In some local- 
ities the plant is allowed to ripen in 
order to develop the seed, which is in 
i demand, 
considerable 
