quarter million acres in Texas and Oklahoma (table 

 2.5). Other Federal agencies administer 1.5 million 

 acres of rangeland, mostly in Texas, Oklahoma, and 

 Florida. 



Productivity — Southern rangelands include both 

 the most and the least productive rangelands in the 

 contiguous States. The southern cordgrass and Ever- 

 glades communities of the wet grasslands ecosystem 

 average from 2 to 4 tons of herbage and browse pro- 

 duction annually. The best sites are capable of pro- 

 ducing 5 tons or more. The arid shrub and grass eco- 

 systems of western Texas are among the least 

 productive rangeland, producing only 200 to 400 

 pounds annually (table 2.6). Between these two 

 extremes are the prairie and Texas savanna eco- 

 systems, which annually average 3,300 and 2,100 

 pounds, respectively. On the best sites, however, they 

 may produce 5,000 to 6,000 pounds of herbage and 

 browse annually. 



Water Areas 



Water areas of the South total 23.4 million acres, 4 

 percent of the section's total area (table 2.1). About 

 70 percent of both the total water area, and the 16 

 million acres in large bodies of inland water, are 

 located in five States — Virginia, Florida, North 

 Carolina, Louisiana, and Texas. The large inland 

 water area includes the lower Mississippi and its 

 major tributaries, the large lakes and waterways of 

 the Mississippi Delta, Lake Okeechobee and other 

 lowland lakes in Florida, and the many large water 

 impoundments constructed throughout the South for 

 flood control, power generation, recreation, and 

 water storage. Small ponds and streams total over 

 3 million acres, and are well distributed throughout 

 the South. 



The natural and artificial inland waters, as well as 

 the 3.6 million acres of coastal bays and estuaries, 

 provide valuable habitat for fish and wildlife. While 

 most waters provide such habitat for resident popula- 

 tions of wildlife on a continuing basis, many water 

 areas in the South — such as the Mississippi Delta — 

 also provide crucial habitat for vast populations of 

 overwintering migratory birds. The areas also pro- 

 vide sites for water based recreational activities 

 enjoyed by millions of people each year. 



The Rocky Mountains and Great Plains 



The Rocky Mountain area stretches from Canada 

 to the Mexican border and includes eight States 

 (Montana, Idaho, Wyoming, Utah, Nevada, Colo- 

 rado, Arizona, and New Mexico). The neighboring 



Great Plains area includes four States (North Dakota, 

 South Dakota, Nebraska, and Kansas). Together, 

 these areas contain 740 million acres, about one-third 

 of the entire land area of the United States. 



This section of the country has a semiarid conti- 

 nental climate in which evaporation usually exceeds 

 precipitation, despite maximum rainfall during the 

 summer. Winters are cold and dry; summers warm to 

 hot. Winter precipitation is greater in mountainous 

 areas than in the plains area. 



This vast section of the country exhibits many 

 landforms. The rolling plains of the Plains States and 

 eastern extremes of the Rocky Mountain States give 

 way to the steep, glaciated terrain of the Rocky 

 Mountains. The Rocky Mountain States are also 

 characterized by high elevation plateaus and interior 

 basins, and the highly eroded tablelands of Utah and 

 Arizona. In southern and western portions of this 

 section — Arizona, New Mexico, Utah, and Nevada 

 — there are extensive desert areas. 



The dominant soil-forming process is calcification, 

 with salinization on the poorly drained soils. Soils 

 often contain an excess of precipitated calcium car- 

 bonate and are very rich in bases. Organic matter 

 content is low except for forested areas and the tall 

 grass prairies. Moisture is generally the most Umiting 

 factor for plant growth. 



The Rocky Mountains have a wide range of land 

 forms and vegetation. 



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