THE SANDY AND SILICEOUS LANDS OF THE OLDER FOKMATIONS. 77 



pastures. In some cases where the soil is looser these prairies are to a 

 slight exteut cultivated and produce excellent crops. 



Through the region of the red uplands run ridges of sandstone, the 

 soils of which are best considered under the next head. 



The red loam lands pass through the Indian Nation also, where they 

 present substantially the same features as in Arkansas. 



(2) In Texas the red loam prairies and timbers overlie the older forma- 

 tions almost entirely J the timbered hills on the eastern part are capped 

 with what are supposed to be Triassic sandstones. (Loughridge.) The 

 timber on these hills is mostly post oak and bhick jack. The valleys 

 are largely prairie, with mesquite timber growth, and with soils vary- 

 ing from a red sandy loam on the uphmds to a darker loam on the flats, 

 sometimes quite clayey. The western i)art of this region is i^rairie, with 

 red loam soils, derived i)resumably from the red clays that api)ear in 

 the bluffs and hillsides of this and the gypsum region. Their geological 

 age is undetermined. (Loughridge.) 



7. THE SANDY AND SILICEOUS LANDS OF THE OLDEE FORMATIONS. 



These comprise — 



a. The cherty lands derived from the impure siliceous limestones of 

 the Subcarboniferous and Silurian formations ; 



b. The sandy, sometimes loamy, soils resting upon the rocks of the 

 Coal-measures, especially in the States east of the Mississii)pi Eiver ; 

 and 



c. The sandy prairie lands of the Indian Territory, which also rest 

 upon the sandstones of the Coal-measures. 



a. Cherty lands. — In East Tennessee, Northwest Georgia, and North- 

 east Alabama the cherty limestones of the Lower Silurian and Sub- 

 carboniferous formations, in their decay, give rise to soils which may be 

 described as light, rather sandy loams, of yellowish or buff colors, and 

 which are usually filled with angular fragments of the chert. In this 

 region the strata are, as a rule, thrown into folds, and the soils in 

 question are found in narrow strips or ribbons, which have the prevail- 

 ing direction of northeast and southwest. On account of the compar- 

 atively indestructible nature of the materials (siliceous limestones) from 

 which the soils are derived, they are also commonly found in ridges, 

 the valleys between being occupied by the red and brown loams of the 

 limestones mentioned in the preceding section. 



In fertility these ridge soils vary greatly. Notwithstanding the un- 

 promising appearance of the soil, because of the rocks which fill it, it is 

 often of considerable fertility, and usually supports a fine growth of 

 white, black, red, black-jack, and post oaks, hickories, and short-leaf 

 pines, the latter making their appearance where the soil is more sandy. 

 The growth on the cherty ridges of both Silurian and Subcarboniferous 

 formations seems to be substantially the same, except that in some lo- 

 calities the ridges of the former appear to be more sterile and have a 



