12 SOILS OF THE EASTERN UNITED STATES. 



face of the Trinity clay is level to slightly undulating and inter- 

 rupted only by low alluvial ridges and depressions formed by old 

 bayous and stream courses. The surface of the type is usually from 

 5 to 15 or 20 feet above the normal water level of the streams which 

 it adjoins. In absolute elevation, the surface of the type ranges 

 from a few feet above sea level to altitudes of about 500 feet along 

 the upper courses of the principal rivers flowing across the Texas 

 Coastal Plain. 



The greater proportion of the Trinity clay is subject to annual over- 

 flow, and for this reason the type is not extensively used for the pro- 

 duction of farm crops. Drainage is also poor over the greater part of 

 the type. 



Where natural or artificial protection is provided for the Trinity 

 clay or where the overflows subside early enough in the spring to 

 permit planting, the type is cleared and occupied chiefly for the pro- 

 duction of cotton, with a considerable acreage of corn as a secondary 

 crop. 



The Trinity clay is competent to produce from three-fourths bale 

 to 1 bale or more of cotton per acre without fertilization. In some 

 areas this yield has been decreased by the ravages of the cotton boll 

 weevil during the past few years, and in such areas increasing 

 acreages of corn are being planted. Even under the conditions 

 brought about by the invasion of the boll weevil, yields of cotton 

 ranging from five-eighths to three- fourths of a bale are still produced 

 upon considerable areas of the Trinity clay. 



The Trinity clay takes leading rank as a corn-producing soil in the 

 Southern States, giving yields of 35 to 60 bushels per acre without 

 fertilization. 



In properly drained areas, which are also protected from overflow, 

 alfalfa constitutes an important and valuable crop, yielding 4 to 5 

 tons per acre. 



In the Texas Gulf coast country both rice and sugar cane are pro- 

 duced upon the Trinity clay, giving good yields and high acreage 

 returns. 



The Trinity clay has little value as a special crop soil, though 

 onions, potatoes, and garden vegetables for home use are not infre- 

 quently produced upon it in certain localities. 



For the proper protection and reclamation of extensive areas of 

 the Trinity clay, the formation of drainage and embankment districts 

 is essential in order that the community rather than the individual 

 may bear the expense and share the benefits to be derived from such 

 improvements. It is probable that 350,000 acres of the type lying in 

 Alabama, Mississippi, and Texas might profitably be reclaimed if such 

 provision for embankment and drainage could be made. Counting 

 the low cost of the land and the moderate average cost for this form 



