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- No. 1 comes from ten miles north of Sierra Blanca, and is a red sandy soil.
- No. 2 is from the valley three miles northeast of Sierra Blanca.
- No. 3 is from ten miles west of north of Sierra Blanca, the grass being excellent.
- No. 4 is from eight miles south of Sierra Blanca. The grass is good, and an excellent growth of mesquite brush.
- No. 5 is from Sierra Blanca.
The noticeable features of these soils are the large quantity of iron they contain, and the comparatively large amounts of potash and phosphoric acid, excepting nitrogen, the two most valuable ingredients a soil could contain. The percentages of lime, carbonic and sulphuric acids are rather small for Texas soils, but still sufficiently large for agricultural needs. One important fact, however, should not go unnoticed. In No. 4 the quantities of lime and carbonic acid are both large, showing that the lime is present as the carbon ate; and on this soil there is not only a good growth of grass, but the mesquite underbrush is thick and weighted with fruit. This is an exception to the general growth of the foothills. Usually there is plenty of nutritious grass, but little else except cacti. In the spot where No. 4 was collected the cactus is entirely replaced by the mesquite. In a general way, we may say there is little doubt but that lime applied to these soils, either as the sulphate, gypsum, or as the carbonate, would be beneficial. The absence of "alkalies" is a very fortunate characteristic of the soils.
ALKALI SPOTS.
The Rio Grande valley, as I observed it, is dotted with spots of alkali. They seem to occur irregularly, anywhere in the valley. Sometimes they have been brought into cultivation, but more frequently they are left alone as