FERTILIZER INVESTIGATIONS The use of fertilizers is often considered as contributing only to increased crop yields. They provide in addition an effective means, and in many sections of the country the most effective means, of maintaining an adequate crop production on less acreage with a resulting reduction in the necessary hours of labor on the farm. Wellbalanced fertilizers permit of a shortened working day for a given crop return by increasing crop yields per acre, by increasing the marketable proportion and quality of the crop, by promoting a healthy vegetative growth with consequent decrease in the loss of crop by disease or by deterioration after harvest and, by hastening maturity, by decreasing losses caused by early autumn frosts and storms. The work of the Bureau in this field has naturally centered about the three essential elements of mixed fertilizer, nitrogen, phosphorus, and potassium, as well as upon the problems of improving fertilizer mixtures in general. NITROGEN In its nitrogen research program the Bureau has made and is continuing to make many fundamental contributions that have been adopted and are now being utilized by industry. A serviceable ammonia catalyst was developed and has been improved from time to time as a result of additional research and study. Necessary experimental data relative to the chemical and physical behavior of the gaseous mixtures involved in the preparation of ammonia have been and are being obtained. The solubilities of various gaseous constituents in ammonia and in water at various pressures and temperatures have been and are being measured. Important advances have been and are being made in the transformation of ammonia into other commercial forms of nitrogen. Among such processes may be cited the development of the procedure for the synthesis of urea. The process employs only the two products from the direct synthetic ammonia process, namely, ammonia and carbon dioxide. By heating a mixture of these in an autoclave a partial conversion to urea takes place. This process is now put into commercial operation at one plant in this country and the product is being employed in the preparation of mixed fertilizers. As a result of this synthetic production of urea it is now obtainable for about 4 cents a pound whereas previously it was far too expensive a chemical to be considered for this purpose. Another recent development is the utilization of ammonia for the production of a fertilizer material by the treatment of peat therewith to form a product with a nitrogen content in some cases as high as 20 percent, part of which is in the form of water-soluble, and part in the form of water-insoluble, nitrogen compounds. The product possesses general physical properties which indicate it to be a valuable conditioner in mixed fertilizers, and as such would prevent caking of mixtures on storage and would cause maintenance of a condition suitable for easy distribution in the field. POTASSIUM In 1911 when a comprehensive potash program was initiated by the Bureau very little was known concerning our potash resources and there was no domestic potash industry at that time. The coun try was dependent on Germany for its potash requirements. The Nation-wide survey of this Bureau undertaken in cooperation with the Geological Survey, disclosed abundant potash resources. Many of these were worked during the war period of high prices and one of the projects, that at Searles Lake, Calif., in which the potash occurs. in the form of salts, has continued as an important producer of potash. With the discovery of these resources the Bureau undertook the development of methods for the recovery of potash from a variety of water-insoluble silicates found in great abundance. Particular attention has been devoted recently to that phase of the problem designed to provide cheap potash for the Middle West and Northwest from the abundant volcanic lavas of Wyoming which are fortunately situated contiguous to the world's greatest known phosphate deposits in Wyoming, Utah, Idaho, and Montana, and contiguous to cheap coal and other raw materials, thus affording very advantageous conditions for the low-cost production of both potash and phosphates. The potentialities of smelting methods, particularly when applied to a mutually fluxing mixture of potash and phosphate rocks, which offer the unusual advantage of yielding two fertilizer essentials in one operation, have been greatly enhanced by tests which demonstrate that local coals can be substituted for coke, formerly considered an essential fuel in such processes. The potash program initiated by the Bureau has succeeded in making the country 60 percent sufficient in its domestic potash needs. PHOSPHATES The discovery of large deposits of phosphate rock in various sections of the country have made the United States independent of foreign sources of this material since 1867. The Bureau has, therefore, directed its investigations in this field toward the conservation of these deposits and the study of methods for the preparation of cheaper and more efficient phosphatic fertilizers. An extensive study of the occurrence, production, reserves, and chemical composition of phosphate rock in the United States has been completed. Aside from its scientific value this work will serve as a fundamental basis for the more rational utilization of the domestic phosphate deposits. The importance of liquid phosphoric acid as a basis for the manufacture of concentrated fertilizers was early recognized by the Bureau and since 1914 a continuous program of research on the preparation of phosphoric acid by furnace processes has been carried on. This program was started with studies of the electric-furnace process, a phase of the work which was completed in 1917. As a result of this investigation the world's first commercial electric-furnace plant for phosphoric acid production was put into operation and has been in practically continuous operation since 1920. Subsequently attention has been directed to the preparation of phosphoric acid by fuel-fired furnace methods. The results of the work initially conducted along this line paved the way for the erection of the world's first commercial blast furnace plant for phosphoric acid. The cost of furnacemade acid is, however, still too high to permit its general use in the manufacture of fertilizers and further work is, therefore, being continued toward improvements in the process. 35962-34-15 FERTILIZER MIXTURES As a result of developments in nitrogen fixation and in potash and phosphate manufacture a number of new fertilizer materials of increased plant food content have come onto the market. When these are used in the preparation of mixed fertilizers an excessive quantity of filler, or inert material, must be included in the mixture if the analysis of the mixture is to be maintained the same as when prepared with the older materials. It was suggested by the Bureau that instead of using filler a more logical procedure would be to increase the plant food content of the mixture as a whole. It was the view of the Bureau that it should be practical to double the plant food content of the fertilizers used in this country which at the close of the war did not exceed 15 percent, and an investigation was accordingly undertaken of the feasibility of making such a radical change in mixed fertilizer technology. During the early stages of the work the feasibility of the project was questioned by most agronomists and fertilizer manufacturers. The investigational work undertaken on the adaptation of these materials to the preparation of more concentrated mixtures involved a study of their chemical and physical properties, their compatability in mixtures and the development of methods for improving their mechanical condition, drillability and fertilizer efficiency. The progress that has been made is attested by the fact that double strengh or concentrated fertilizers, as they are commonly called, are now being successfully used in all fertilizerconsuming States. Mixtures of this kind not only cost less to handle and ship but they also cost less to produce per unit of plant food than the lower analysis mixtures of the ordinary types. It is estimated that farmers who demand high analysis, or concentrated fertilizers, are now able to effect a saving of upwards of 25 percent in their fertilizer bill over those who use only low analysis fertilizers. FERTILIZER PLACEMENT STUDIES With the event of more highly concentrated fertilizer mixtures and the slump in the prices of farm products there has developed the need for more efficient methods in the application of commercial fertilizers. Including actual crop injury and the improper utilization of plant food it is estimated that the losses to potato growers alone, due to wrong usage and improper placement may amount to as much as $10,000,000 annually. During the past 2 or 3 years the Bureau has given a great deal of attention to the proper placement of fertilizer in the soil with respect to the seed. Best results have been obtained for such crops as corn, cotton, and potatoes when the fertilizer is applied in bands to the side of the seed and at a distance of about 2 inches from the seed. When this practice is followed the distribution of the fertilizer and the planting of the seed can be accomplished by one operation which results not only in increased acre yields but in decreased cost of operation. Work on this problem is in progress in Michigan, Ohio, and New Jersey, in cooperation with State experiment stations. The results of the Bureau's fertilizer investigations program, as carried on and in cooperation with industry and the farmer, may be summarized as follows: (1) The establishment of a nitrogen fixation industry comparable to the country's requirements for peace-time industry and national defense; (2) the establishment of a domestic potash industry which adequately guarantees against future shortage or monopolistic price control by foreign producers; (3) improved phosphate and mixed fertilizer production; (4) savings in the American farmer's fertilizer bill estimated at $45,000,000 for a normal year (1929 or 1930) or about $25,000,000 for the current year due to restricted consumption. SOIL CLASSIFICATION AS A BASIS FOR LAND-USE PROGRAMS The classification and mapping of the soils of the United States has been and continues to be one of the major activities of the Bureau of Chemistry and Soils. In addition to furnishing basic information for the farmer, soil-survey reports and maps serve a valuable purpose in the development of the work of the agricultural experiment stations and in the farm-management plans developed by the county agricultural agents. Experimental results obtained on a soil type in one region may be applied to similar soil types in other regions where sufficient knowledge of the soil is available. The character of the soil is a most important factor in land appraisals. Federal land banks, insurance companies, tax assessors, and State officials are making extensive use of our soil-survey maps and reports wherever they are available. During the past year the demand for soil maps has been far in excess of that of former years and in many cases has entirely exhausted the available supply of publications. The surveys are used by the National Parks Service in valuating lands involved in the improvement of national parks; by the Indian Bureau for the classification and allotment of Indian lands; by the Bureau of Standards in the study of the effect of soil on pipe-line corrosion; by the War Department in appraisal of lands taken under condemnation proceedings; by the Navy Department in passing on the character of soil surfacing materials for use on airplane landing fields and by various other Government agencies. The soil-survey maps and reports have been extensively used by State and other public agencies in the preparation of land-use maps, conservation reports, and more recently by the Bureau of Agricultural Economics in the preparation of a national land-use map for the National Planning Committee and similar State and Federal agencies. It is now clearly recognized that constructive work in agricultural adjustment in the United States must be based on accurate and detailed knowledge of the adaptabilities and productivity of the land of the country. Such a land classification is impossible without the basic information contained in the soil survey reports and maps. this information had not been gathered previous to the development of this demand, it would be impossible to collect it in any reasonable number of years, since its accumulation has not been and would not be merely a matter of going over the ground but a matter of working out methods and training a staff of technical workers. SOIL FERTILITY INVESTIGATIONS-SUGAR BEET SOILS The response of soils of different types to the use of commercial fertilizers varies considerably and growers have even sustained losses in both yields and quality by the application of fertilizers unsuited to their soil conditions. The work of the Bureau of Chemistry and Soils has shown the possibility of obtaining an average increase of 3 tons of sugar beets per acre by the use of suitable fertilizer mixtures, thereby greatly decreasing the unit cost of production. It is estimated that this increase if applied to the industry as a whole would increase the income of domestic growers approximately $12,000,000 annually. The study of the effect of applications of suitable fertilizers to the sugar beet has led to their use for other crops, in the sugar beet regions, including alfalfa, the yield of which has, in some instances, been more than doubled by the fertilizer treatment. SUGAR-CANE SOILS Sugar cane for the production of sugar is grown in continental United States in the States of Louisiana and Florida to the extent of approximately 177,000 acres. Soil fertility field work on sugar cane soils is in progress at a station at Houma, La., in cooperation with the Louisiana Agricultural Experiment Station and the American Sugar Cane League. These fertilizer and soil fertility investigations are conducted on experimental fields of soils which are representative of the major types prevailing throughout the sugar cane belt. The work has demonstrated that the presence of available nitrogen in the soil is essential to the successful growth of the plant. It is also shown that good results may be obtained by the application of a well balanced complete fertilizer. The tests conducted in 1931 showed increase yields on the fertilized plots varying from 3.6 to as much as 10.3 tons of sugar cane per acre and from 596 to 1631 pounds of sugar per acre as compared with yields from the unfertilized plots. On the other hand some of the plots treated with fertilizers have failed to show any increase over the unfertilized plots, a response from the different fertilizer mixtures varying with the different soil types. Evidence from our results show that the use of a suitable fertilizer mixture is profitable but that the use of a mixture not suited to the soil type may result in loss to the grower both in cost of the fertilizer and in some cases a possible reduction in yield of sugar. This investigation is developing the information necessary for the profitable use of fertilizers with the consequent decreases in unit production. PECANS The Bureau of Chemistry and Soils is cooperating with the Bureau of Plant Industry and with the pecan growers in a study of the fertilizer requirements of some of the more important soil types on which pecan groves are being developed. Results to date indicate that the use of properly balanced fertilizers will produce not only increased yields but improved quality of nuts. SOIL STUDIES ON THE ROOT ROT OF COTTON This is a most serious disease of the cotton plant in Texas and is becoming a problem in Arizona, New Mexico, and California. It is also found in Oklahoma, Arkansas, and Mexico. Loss from root rot for Texas for all crops is approximately $100,000,000 annually. No means of eradication on filed scale have been devised but measures of control have been developed that offer promise. In 1928 the Bureau of Chemistry and Soils in cooperation with the Texas Agricultural Experiment Station, the University of |