Soils investigations and laboratories

Since mid 1953 when all soil survey activities of the Department were consolidated in the Soil Conservation Service, considerable effort has been devoted to developing a scientifically sound system of soil classification that would be acceptable to soil scientists throughout the world and to gathering all of the data for each individual soil that would provide needed information for all present and prospective users of the soil survey.

Soil survey investigations involving both field and laboratory work are being conducted for the purpose of (1) characterization of soils so that they may be placed appropriately in a nationwide system of soil classification; (2) the characterization of soils with regard to their behavior under various systems of soil management; and (3) improvement in the understanding of soil genesis and how soils act under cultivation.

The Service operates three principal soil laboratories at Beltsville, Md., Lincoln, Nebr., and Riverside, Calif., to make both physical and chemical soil analyses primarily in support of the soil survey field mapping program. Cooperative arrangements have been made in the States of Colorado, New Mexico, Tennessee, Utah, and Virginia with the experiment stations of the land grant colleges for soils laboratory assistance in both the soil surveys and the application of conservation practices. Many other agricultural experiment stations maintain soils laboratories that aid the soil survey work. A soil mechanics laboratory serving the entire Nation is also operated at Lincoln, Nebr., to test soils for structural work.

Some 211 soils were analyzed in the 3 principal laboratories for soil characterization during the year. This required some 30,000 separate analyses of almost 1,600 samples. In addition more than 3,000 other miscellaneous analyses were made on an additional 1,500 samples. Mineralogical determinations including X-ray, differential thermal analyses, and various quantitative petrographic and special chemical determinations were also made on about 400 additional samples. The investigation of soil composition in relation to parent material source in the Monument Valley of Arizona and in southern Utah and of the microstructure of some prairie soils of western Iowa were completed. Studies of the effect of cobalt in the soils of the Southeastern States and of molybdenum in Nevada are continuing. More accurate interpretation of soil survey data in the southern Great Plains is being developed through a climatological study related to soils data. Studies of tropical soils and some laterite materials in Hawaii and southern California continued. The study of cemented hardpans and fragipans has been enlarged by the collection of a set of samples of desert soils containing alkali soluble hardpans and samples of fragipan soils from glacial till in New England. Field work for a study project on the genesis of brown, swelling, clay soils derived from volcanic rock covering large areas in north central Arizona was completed and the laboratory work was started. Studies on the fundamental properties of clay soils continued. Technical papers are published whenever a significant contribution can be made to the literature on the subjects studied.

Significant progress has been made in forest site-soil relationship studies and data developed are contributing to the quality of conservation programs in several States. A study of the relationship of range sites and soils is being initiated.

Soil-survey reports

During the fiscal year 1957, 29 soil-survey reports with accompanying maps were sent to the Government Printing Office for publication. A total of 47 of these reports were awaiting publication at the close of the fiscal year. New soilsurvey reports and maps were published for the following areas: Prentiss County, Miss.; Livingston County, Mo.; Cherry County, Nebr.; Livingston County, N. Y.; Noble County, Okla.; Johnson County, Tenn.; Sevier County, Tenn.; Faquier County, Va.; Skamanie County, Wash.

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This brings to 1,676 the number of soil-survey reports published since the work began in 1899. Many of the earlier surveys do not provide the detail or useful data for current needs and are scheduled to be revised and republished. increased rate of soil survey report, preparation, editing, and publication is scheduled for 1958 and 1959.

During the fiscal year 1957, a total of 122,492 additional farmers and ranchers became district cooperators, which increased the cumulative number of cooperators to 1,727,682, as of June 30, 1957. Changes in ownership, death and cancellations caused a loss of 38,876 cooperators during the year, resulting in a net increase of 83,616 cumulative cooperators in 1957. Likewise, a total of 92,660 basic conservation plans were developed in 1957. However, losses such as those above resulted in a net increase of only 58,941 basic plans on hand as of June 30, 1957. Basic conservation planning in soil conservation districts

As of December 31, 1956, the Soil Conservation Service was cooperating under formal agreement with 2,744 conservation districts in the 48 States and in Alaska, Hawaii and the Caribbean area.

Of the 1,559,667,362 acres total land area in the 2,725 districts to which technical assistance was provided as of December 31, 1956, about 1,127 million acres were agricultural land on which the Service, in cooperation with districts was authorized to work. This acreage consisted of about 4,686,000 operating farms and ranches which is approximately 87 percent of the total land in farms and 91 percent of the farms and ranches in the United States.

Basic conservation plans had been prepared with SCS assistance on nearly 1,139,000 farms and ranches comprising about 318 million acres of agricultural land as of December 31, 1956. This was about 24 percent of all the operating units in districts and about 28 percent of the agricultural land in districts. Variations in these percentages by States and broad geographical areas are shown in the table on the following page.

The Service's long-term objective recognizes that nationally basic conservation plans need a major revision within a 10-year period to keep them up to date. The annual workload on these revisions would be about 10 percent of the plans on hand for any given year. However, during calendar years 1955 and 1956, the reported revisions each year were less than 1 percent of the plans then on hand.

Basic conservation planning in soil-conservation districts by States and nationally, Dec. 31, 1956

Progress in farm and ranch planning

The table on the following page shows by States the number of districts which had from 10 percent and less, to more than 50 percent of their agricultural land included in basic conservation plans for farms and ranches. Of the 2,725 districts to which assistance in farm and ranch planning had been provided as of December 31, 1956, more than 50 percent of the agricultural land in 371 districts was covered by basic conservation plans, or 13.6 percent of the total districts. Another 1,219 districts were between 20 and 50 percent planned. The remaining 1,135 districts were less than 20 percent planned. The acreage of agricultural land in each of the districts, on which these percentage calculations were based, include the public and private land on which the Soil Conservation Service is authorized to work through memoranda of understandings and other working arrangements.

Only 133 districts in 26 States had 65 percent or more of the agricultural land planned, which was 4.9 percent of the total districts assisted. These were mainly small districts with a small number of operating units, or those located in relatively level bottom-land areas, or a combination of small irrigated acreages with larger grazing areas. Even in the districts with higher percentages of agricultural land planned, many smaller operating units remained to be planned.

In many districts, frequent changes or revisions are made in basic plans already prepared to keep them up to date. Changes in ownership, and land-use adjustments for different types of farming, often cause replanning of farms and ranches to meet the needs of operators. The Soil Conservation Service provides technical help to district cooperators in making such change or revisions in basic plans.

Acreage of basic plans related to agricultural land as of Dec. 31, 1956

Includes all public and private land on which the SCS is authorized to work, i. e., the cropland, grassland, woodland, wildlife, and other land used for agricultural purposes within the boundaries of soil

conservation districts.