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NATURALIST'S GUIDE TO THE AMERICAS 



Mountains, and extending in a general 

 northerly direction to the Kansas line. 

 Its boundaries are not everywhere 

 sharply defined. The surface of this 

 region is rough and the hill-tops are 

 frequently capped with sandstone ledges 

 some 300 to 400 ft. above the lowlands. 

 The slopes are covered by sandstone 

 boulders which render them unfit for 

 farming. The valleys are rich and 

 thickly populated, while the hills are 

 sparsely settled. 



The Redbeds Plains Region comprises 

 the greater part of the central portion 

 of the state from the Kansas line to the 

 Red River and extending thence west- 

 ward to surround entirely the Wichita 

 Mountains. This is in general a slightly 

 rolling plain sloping to the southeast. 

 The streams are of the type common on 

 the plains, where the shallow current 

 flows in a small meandering channel 

 back and forth across the broad shallow 

 valley, deeply choked with sand. Dur- 

 ing most of the year the larger rivers, 

 like the South Canadian and the Cimar- 

 ron, are mere creeks with beds of deep 

 and treacherous quicksand, though in 

 early summer after the spring rains and 

 the melting of the snow in the Colorado 

 mountains, they become raging torrents 

 often two miles in width which sweep 

 every obstruction away in the mad rush 

 of the water down-stream. The banks 

 are formed by considerable areas of sand- 

 dunes, among which, here and there, 

 occur ox-bow bayous (locally called 

 "lakes") which mark abandoned por- 

 tions of previous river-beds after the 

 streams have cut new channels across 

 the bends. Over most of this region the 

 surrounding country never reaches an 

 elevation of more than a hundred feet 

 above the water level, and usually much 

 less, wide areas being subject to over- 

 flow during times of high water. While 

 over most of the Redbeds Plains timber, 

 principally elm and cottonwood, occurs 

 only along the streams, the extreme 

 eastern portion supports a growth of 

 scrubby blackjack oak. This was the 

 first portion of the state thrown open to 

 settlement, and the population is fairly 



dense and well established. Railroad 

 facilities are good and the roads, while 

 often mere trails, are in the main well 

 graded and satisfactory for motor 

 travel, especially in pleasant weather. 



The Gypsum Hills Region is an irregu- 

 lar area lying to the west of the Redbeds 

 Plains, and extending from the Kansas 

 line to the Red River, including the 

 southwest corner of the state. In 

 general characteristics these two regions 

 are similar. Among the "gyp" hills, 

 however, the streams have generally cut 

 deeper channels which, in the northern 

 portion particularly, have the form of 

 narrow canyons 200 to 400 ft. deep. The 

 surface as a whole slopes rather rapidly 

 to the southeast. Numerous ledges of 

 gypsum (calcium sulphate) occur in the 

 hills and the water in the streams is often 

 so impregnated by the "gyp" in solution 

 as to be most unpalatable. These 

 streams, except the Washita, are typical 

 plains streams with sand-choked chan- 

 nels and broad belts of sand dunes along 

 their courses. The Washita carries 

 much less sand and as a rule has steep 

 mud banks. Agriculture depends upon 

 the so-called "dry-farming" method and 

 the kaffirs and other sorghums constitute 

 the chief grain crops. In several locali- 

 ties there are large springs of salt water 

 which emerge from the red rocks below 

 the gypsum ledges, and, especially in the 

 neighborhood of the Cimarron River, 

 several salt plains occur, which in the 

 dry season have the appearance of a 

 heavy fall of snow owing to the white- 

 ness of the salt which covers the surface 

 to the depth of several inches, over 100 

 sq. mi. of territory. 



The Sand Desert Region covers an area 

 of 3000 to 4000 sq. mi. in the extreme 

 western part of the state from the 

 Texas line eastward between the Cimar- 

 ron and South Canadian Rivers. This 

 is region of dry shifting sand and sand 

 dunes almost wholly devoid of trees or 

 other prominent vegetation. It is ut- 

 terly useless for any sort of agriculture 

 and as barren as the Sahara. 



The High Plains Region comprises 

 all the rest of the state, including the 



