REPORT OF THE CHIEF OF THE BUREAU OF SOILS. 



United States Department of AGRicuLlnjRE, 



Bureau of Soils. 

 Washington, D. 6'., September 11, 1918. 

 Sir : I have the honor to transmit herewith a report covering the 

 operations of the Bureau of Soils for the fiscal year ended June 30, 

 1918. 



Respectfully, ^ Milton Whitney, 



Chief of Bureau. 

 Hon. D. F. Houston, 



Secretary of Agriculture. 



SOIL SURVEY. 



Notwithstanding a certain amount of interruption in the work of 

 the soil survey, due to war-time conditions, a larger area of detailed 

 mapping was done during the fiscal year 1918 than during the pre- 

 ceding year, the area covered amounting to 38,136 square miles. 



Prior to this year a total of 445,825 square miles had been mapped, 

 so that the total area covered by the detailed work of the survey 

 at the close of June 30, 1918, was 483,961 square miles. That part 

 of the United States lying within regions where the rainfall is 

 sufficient for crop production or where water is available for irriga- 

 tion covers approximately 1,750,000 square miles. The area mapped 

 in detail during 1918 was equal to approximately 2.2 per cent of 

 this area, the total mapped in detail to date to 27.6 per cent, and 

 the total, both detail and reconnoissance, much of the latter area 

 calling for no further work, to 54.3 per cent of it. 



Keconnoissance soil mapping was carried on in California only in 

 1918, where an area of 4,735 square miles in the southern part of the 

 State was covered. 



Of the 38,136 square miles mapped in detail, all except 4,429 miles, 

 distributed in five States, was done in active cooperation either with 

 some State organization or with some of the bureaus of the United 

 States Government. Four of the five States in wdiich no cooperation 

 was given cooperated in this work in former years but were obliged 

 to drop it for the present on account of war conditions. In a few 

 other States no work -3 undertaken, owing to temporary inability 

 of these States to continue active cooperation under existing condi- 

 tions. At the close of the fiscal year active cooperation in soil-survey 

 work was in operation with 22 States and with four bureaus of the 

 Federal Government. 



The statistical details of the work of the survey are shown in the 

 accompanying tables. 



Of the total area mapped in detail during the year, 11,936 square 

 miles lay within the cotton belt, 4,410 square miles in the Pacific 

 Coast States, and 21,790 square miles in the rest of the country. 



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