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The National Geographic Magazine 



With a more thorough knowledge of 

 the soil and its adaptation to crops and 

 the proper methods of soil management, 

 the full extent of the agricultural de- 

 velopment which may take place in the 

 United States in the future is very great. 

 The undeveloped portions of the United 

 States are not confined wholly to the arid 

 West. When we realize that we have 

 77,000,000 acres of swamp land in the 

 eastern half of the United States — an 

 area equal to all of the New England 

 States, New York, and half of Pennsyl- 

 vania, or to the combined areas of Illinois 

 and Iowa — which can be reclaimed, and 

 which, under the prevailing climatic con- 

 ditions when so reclaimed, are exceed- 

 ingly productive, and when we realize 

 that only 16 per cent of the State of 

 Louisiana, for example, and a smaller 

 percentage of the State of Texas is in 

 improved lands, the possibilities of de- 

 velopment become more apparent. 



The soil survey work of the depart- 

 ment is the largest undertaking of the 

 kind that has ever been inaugurated in 

 any country. The area surveyed and 

 mapped during the past fiscal year was 

 20,560 square miles, or 13,158,400 acres, 

 and there have been completed to June 30, 

 1907, surveys covering a total of 139,- 

 247 square miles, or 89,118,080 acres. 

 This area is more than 15 per cent of the 

 amount represented by the farm lands of 

 the United States. The work has been so 

 distributed as to include every large rep- 

 resentative district in the United States. 



One of the most important problems 

 being studied by the department is the 

 intelligent use of commercial fertilizers. 

 In some sections of our country, es- 

 pecially in the South and East, the quan- 

 tities now used are enormous, and this 

 use is gradually extending. That the 

 amount of money annually invested in 

 fertilizers by the farmers of the country, 

 now amounting to upward of $100,- 

 000,000, will continue to increase seems 

 certain. But just as certainly a large 

 percentage of the money — perhaps a 

 third — is annually wasted and brings no 



adequate return, owing to a lack of un- 

 derstanding of the soil's requirements. 



According to the latest determinations 

 the rivers of the United States are 

 annually pouring into the seas fully 

 1,000,000,000 tons of sediment. The 

 volume of material thus lost to the land is 

 increasing with settlement and cultiva- 

 tion ; it is almost wholly washed from the 

 surface and is the very richest soil ma- 

 terial, the cream of the soil. The value 

 of the material is not easily fixed, but at 

 a moderate appraisal the annual loss 

 would exceed all the land taxes of the 

 country. 



Part of this wastage may be avoided 

 by deeper cultivation, drainage, terrac- 

 ing, etc., to which effective and simple 

 methods the public is being educated by 

 the department. 



THE BOLI, WEEVIL CHECKED 



That the cotton-growers can be pro- 

 tected from the boll weevil by planting 

 cotton early and by burning the plants in 

 the fall, after the cotton has been har- 

 vested, has been proved by many experi- 

 ments of the entomologists of the depart- 

 ment. In one isolated locality in Calhoun 

 and Jackson counties, Texas, badly in- 

 fested with the weevil, 410 acres, com- 

 prising all of the cotton in that vicinity 

 and separated from other cotton plant- 

 ings by about 10 miles, were cut during 

 the first ten days of October, 1906. In 

 Lavaca county, 30 miles away, a consid- 

 erable quantity of cotton was not de- 

 stroyed, and the fields were kept under ob- 

 servation as a check. The results were 

 as follows : 



In May, 1907, in the experimental fields 

 only one weevil was found, whereas in 

 the check fields the weevils were so num- 

 erous that practically all of the squares 

 had been destroyed. In September, 1907, 

 the cotton in the experimental fields 

 showed a yield of about 1,000 pounds of 

 seed cotton per acre, while in the check 

 fields the average was about 350 pounds 

 of seed cotton per acre, and this in spite 

 of the fact that the soil on the check area 



