LIBRARY. A 8c M COLLEGE» flfl-NELQ TEXAS AGRICULTURAL EXPERIMENT STATION A. B. CONNER, DIRECTOR, College Station, Texas BULLETIN NO. 602 JUNE 1941 FERTILIZER FOR RICE IN TEXAS R. H. WYCHE Division of Agronomy AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS T. C. WALTON, President A145-641-7M-L180 [Blank Page in Original Bulletin] Fertilizer experiments with rice conducted on Lake Charles and Crowley clay soils at the Rice Experiment Station, Beaumont, Texas, from 1930 to 1940 show definitely that these soils respond more readily to applications 0f nitrogen than to. phosphate fertilizers. Moderate applications of sulfate of ammonia, 100 to 150 pounds per acre, have given more profitable results than lighter or heavier applications. Superphosphate alone did not produce any appreciable increases in yield, although a combination of superphos- phate and sulfate of ammonia produced larger yields than the latter alone during the last few years of the test. In the cooperative experiments in the rice-growing area, however, dif- ferent soils responded differently to fertilizers applied to rice. In the experiments on Lake Charles clay soil near Devers, in Liberty County, and on the light-colored soils in Orange County, applications of super- phosphate produced larger yields of rice than applications of nitrogen. These soils have not been planted regularly to rice and may be considered comparatively new land. On the other hand, in the tests near Nome in Jefferson County, which were conducted on Lake Charles and Crowley clay soils that have been grown to rice every second or third year for a long time, nitrogen (in sulfate of ammonia) gave better results than super- phosphate. In all of these cooperative experiments a combination of sulfate of ammonia and superphosphate produced larger yields of rice than either material alone. These results indicate that new lands are first in need of phosphate for rice. Under long cultivation, however, the nitrogen becomes depleted and the soil responds to both nitrogen and superphosp-hate. Nitrate of soda, uramon, and sulfate of ammonia produced practically the same yields of rice. The various phosphates, bone meal, superphosphate, and granular superphosphate, also gave essentially the same results. Although applications of potash have produced small increases in yield of rice, the. increases were not large enough to justify the general use of potash for rice. Applications of manganese, iron, copper, zinc, and boron did not increase the yield of rice. Applications of fertilizers in the drill with the seed at planting time produced approximately 12.5 per cent larger yields than applications broad- cast on top of the soil. Considering the results of all phases of this fertilizer work, the appli- cation of a mixture of 100 pounds of sulfate of ammonia and 100 pounds of superphosphate per acre (which supplies 20 pounds of nitrogen and 20 pounds of phosphoric acid) in the drill with the seed at planting time has been the most satisfactory fertilizer practice for rice. CONTENTS PAGE Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Object and Method of Conducting the Work . . . . . . . . . . . . . . . . . . . . . . . . .. 5 Soils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6 Cultural Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6 Results Secured with Different Kinds and Rates of Fertilizers . . . . . . . . . . 6 The Experiments from 1930 to 1940 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 Methods of Applying Fertilizers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Comparison of Different Nitrogenous and Phosphatic Materials . . . . . . . . 12 Cooperative Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Tests near Nome . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 14 Tests in Liberty County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 14 Tests in Orange County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 15 Work with Manganese, Copper, Zinc, Iron, and Boron . . . . . . . . . . . . . . .. 16 Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 16 Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 17 Literature Cited . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 18 FERTILIZERS FOR RICE IN TEXAS R. H. Wyche, Superintendent Substation No. 4, Beaumont Rice has been grown in America for about 255 years, since its intro- duction into the Colony of South Carolina in 1685 (4). The industry later spread to adjacent states. A limited amount was probably grown in Texas about 1863. However, the crop did not become of any great importance until about 1900. At present the most important rice-pro- ducing area of the United States is located in southwestern Louisiana and southeastern Texas. The average annual acreage in Texas from 1915 to 1935, inclusive, was 188,905 acres, which produced 7,742,952 bushels of rice with an annual value of $8,349,333 (1). This is about 20 per cent of the total production in the United States. The topography of the Gulf Coast Prairie of Texas is very fiat with a fall of approximately one foot per mile towards the Gulf of Mexico. This fall is very favorable to the irrigation of rice with a small number of levees, and yet is sufficient for fairly good drainage. The larger part of the soil is a heavy clay with a very impervious subsoil. This type of soil requires a minimum amount of irrigation water, and will support heavy machinery at the time of harvest during a rainy season. In addition, a long growing season with fairly high seasonal temperatures and a heavy annual rain- fall are climatic conditions that are very favorable to the growing of rice. A fairly plentiful supply of irrigation water is available from the Neches, Trinity, Brazos, and Colorado rivers. Also Water is obtained from wells in a few localities and from bayous in certain sections. Object and Method of Conducting the Work The earlier work with fertilizers on rice at the Beaumont Station was published in Texas Agricultural Experiment Station Bulletin 398 (2). The application of sulfate of ammonia alone or in combination with super- phosphate had given consistently good results under the particular con- ditions. The soils in the rice-growing area of the state, however, vary a great deal with respect to type, fertility, and length of time in cultiva- tion. Consequently it would be expected that they would differ in their needs for fertilizers. These differences are recognized by rice growers who use fertilizers, and among whom there are difierences of opinion as to the correct fertilizer practice. In order to secure additional information on various phases of fertilizer practice for rice in different parts of the rice-growing area of the state new experiments were begun in 1930. The new work embraced some of the better treatments from the previous work and included tests at Beau- mont on different kinds and rates of application of fertilizers, methods *Numbers in parenthesis refer to List of References at the end of this publication. 6 BULLETIN _NO. 602, TEXAS AGRICULTURAL EXPERIMENT STATION of application of fertilizers, tests with nitrogenous and phosphatic ma- terials, and cooperative fertilizer tests with rice growers in different localities. Soils All of the fertilizer work on the Experiment Station farm at Beaumont and at Nome in Jefferson County was conducted on Lake Charles and Crowley clay soils, the former being the principal rice soil in the state. The tests near Devers in Liberty County also were conducted on Lake Charles clay or clay loam soil. The cooperative tests in Orange County were located on light-colored soils, probably of the Katy series. The soil type, however, was not identified definitely because the soils of the county have not been mapped in detail. Cultural Practices The land on the Station farm was cropped to rice every other year and was summer plowed during the years it was not in rice. The land in the vicinity of Nome had been cropped somewhat similar to that on the Station until some seven or eight years ago and has since been planted to rice once in three or four years, being pastured and then summer plowed during the year preceding the planting of rice. The land used in the test at Devers in 1935 was planted to rice for the second consecutive year, but had never been in rice prior to 1934. The land used in 1938 and 1940 had been cropped to rice rather regularly a number of years ago, then pastured for several years and then used for rice every second or third year for the past six or seven years. ‘The land used in the Orange County test in 1939 had been planted to rice in 1938, but had not been in rice for about fourteen years prior to that time. The land used in 1940 had been planted to rice in 1937 and 1938, but had not been used for rice for some fourteen or more years preceding 1937. All of these tests were planted on land that had been plowed to a depth of three to five inches the preceding summer or fall, and then disced and harrowed. All of the rice was planted with a small eight-hole drill. The remainder of the cultural practices were essentially the same as described in Farmers’ Bulletin No. 1808 (4). A Results Secured with Different Kinds and Rates of Fertilizers This work was conducted at Beaumont on Lake Charles and Crowley clay soils. In the earlier years the plats were 1/10 of an acre in size, and usually the treatments were not replicated. From 1921 to 1929 the plats were from 1/ 33 to 1/ 22 of an acre in size, and each fertilizer treatment was repeated two or more times. Plats of 1/33 of an acre in size have been used since 1930, and each treatment was repeated four times. The results of the FERTILIZER. FOR RICE IN TEXAS 7 experiments from 1915 to 1929, as reported in Bulletin N0. 398, are sum- marized in Table 1, for comparison with the data presented in Table 2 covering the experiments from 1930 to 1940. I In the earlier experiments sulfate of ammonia used at the rate of 100 pounds per acre produced the largest yields of rice during the first six and eight-year periods, and the fourteen-year period. The increases over the unfertilized plats Were 739, 682, and 519 pounds per acre, respectively, for these_periods. Four additional treatments were included in the last six years of the test, 1924 to 1929. During this period a combination of 200 pounds of sulfate of ammonia, 300 pounds of superphosphate, and 100 pounds of potash per acre produced the largest yield of rice, which was 526 pounds per acre more than the yield of the untreated plats. However, 100 pounds of sulfate of ammonia alone increased the yield 302 pounds for this period. Table 1. Acre yields of rice secured from diflerent kinds and rates of fertilizers from 1915 t0 1929 Fertilizer treatment Average yield in pounds for Lbs. Six Eight Fourteen Six per Material years years years years acre 1915-21 1915-23 1915-29 1924-29 No treatment . . . . . . . . . . . . . . . . . . . . . . . . . . 1775 1770 1745 1711 50 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1890 100 Sulfate of ammonia . . . . . . . . . . . . . . . . . . .. 2514 2452 2264 2013 200 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2056 75 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1825 150 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . 2140 2030 1966 1880 300 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1682 50 Sulfate of ammonia 75 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . 2160 2094 2017 1915 100 Sulfate of ammonia 150 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . 2350 2236 2132 1994 200 Sulfate of ammonia 300 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . 2503 2433 2191 1868 300 Cottonseed meal . . . . . . . . . . . . . . . . . . . . . . . 2130 2075 . . . . . . . . . . . . . . . . . . . . 300 Cottonseed meal l 150 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . 2062 1976 . . . . . . . . . . . . , . . . 12,000 Manure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1721 . . . . . . . . . . . . . . . . . . . . . . . . _ , _ _ _ , 12,000 Manure 150 Super-phosphate . . . . . . . . . . . . . . . . . . _ . . . . . 1952 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200 Sulfate of ammonia 300 Superphosphate 100 ulfate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2237 300 Superphosphate 100 Sulfate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2084 200 Sulfate of ammonia 100 Sulfate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1858 100 Sulfate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1733 8 BULLETIN NO. 602, TEXAS AGRICULTURAL EXPERIMENT STATION The Experiments from 1930 to 1940 The fertilizer work at Beaumont with different rates and kinds was ex- panded in 1930 in line with the trend of previous results and included several new treatments. In this work the fertilizers were applied broadcast on top of the soil at planting time during the years of 1930 to 1936. Results obtained from some of the other work with fertilizers on rice have shown that placing the fertilizers in the drill with the seed gave larger yields than similar treatments applied on top of the soil. For this reason, all fer- tilizers were applied in the drill with the seed during the years 1937 to 1940. Sulfate of ammonia and superphosphate were used alone and in combination at several different rates. Potash, also, was used in combina- tion with sulfate of ammonia and superphosphate. The fertilizer treat- ments and the average yields of the groups of treatments are given in Table 2. Sulfate of ammonia was applied alone at the rates of 50, 100, 150, and 200 pounds per acre. As will be observed in Table 2, the yield of rice increased with the rate of application of the sulfate of ammonia. The average yield of the four rates of application was 2,430 pounds of rice per acre, or 15.2 per cent more than the yield obtained from the unfer- tilized soil. It would seem, however, that 150 pounds per acre is about the most practical rate to‘ use. The use of superphosphate alone at all rates of application apparently reduced the yield of rice, the reduction increasing roughly with the increase in application, as shown in experiments included in Table 2. When the Figure 1. Rice Fertilizer test at Substation No. 4. Right, no fertilizer. Left, 200 pounds sulfate of ammonia and 100 pounds superphosphate per acre. FERTILIZER FOR RICE IN TEXAS 9 Table 2. Acre yields of rice from different kinds and rates of fertilizers from 1930 to 1940 Fertilizer treatment Increase over unfertilized soil Lbs. _ Yield in per Material pounds acre Pounds Per cent No fertilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2109 . . . . . . . . . . . . . . . . . . . . 5O Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2225 116 5.5 100 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2328 219 10.4 150 Sulfate of ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2515 406 19.2 200 Sulphate 0f ammonia . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2653 544 25.8 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2430 321 15.2 50 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2034 —— 75 — 3.4 100 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2004 —105 — 5.0 150 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1840 —269 —12.8 200 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1872 —237 —-11.2 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1938 —171 — 8. 1 100 Sulfate 0f ammonia 40 Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2218 109 5.2 100 Superphosphate 40 Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 1909 ——200 — 9.5 100 Sulfate of ammonia 100 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2158 49 2.3 100 Sulfate of ammonia 150 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2301 192 9. 1 100 Sulfate of ammonia 200 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2309 200 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225s 147 100 Sulfate of ammonia 100 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2158 49 2.3 150 Sulfate of ammonia ‘ 100 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2479 370 17.5 200 Sulfate of ammonia 100 Superphosphate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2568 459 21.8 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2402 293 13.9 100 Sulfate of ammonia 100 Superphosphate 40 Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2266 157 7.4 100 Sulfate of ammonia 200 Superphosphate 40 Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2153 44 2.1 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2210 101 4.8 100 Sulfate of ammonia 100 Superphosphate " 40 Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2266 157 7.4 200 Sulfate of ammonia 100 Superphosphate 40 Muriate of potash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2513 404 19.2 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2390 281 13.3 10 BULLETIN NO. 602, TEXAS AGRICULTURAL EXPERIMENT STATION yields of rice obtained from the four rates of application of superphosphate are averaged, a yield of 1,938 pounds of rice per acre is obtained. This is 171 pounds, or 8.1 per cent, less than the average yield of the unfertilized soil for the 11 years 1930-40. The reduction in yield caused by super- phosphate has been attributed to an increase in growth of grasses which compete with the rice for plant food, especially nitrogen. Similar observa- tions have been noted in the rice areas of Arkansas and Louisiana. This reduction in yield may be avoided by the application of superphosphate, on soils needing phosphoric acid, a month or six weeks after the rice is planted. The injury also may be reduced or avoided by drilling the super- phosphate in with the seed as the young rice plants will have a better chance of utilizing the plant food before any great amount is taken up by the grasses. This subject is discussed more fully in Bulletin 398. Potash was used in combination with sulfate of ammonia, with super- phosphate, and in a complete fertilizer. In general, potash did not produce increases in the yield of rice in any combination used. Methods of Applying Fertilizers As stated earlier in the bulletin it had been observed that applying superphosphate at the time the rice was planted reduced the yield as com- pared with applications made six weeks after planting. The work of other investigators on methods of applying fertilizers to other crops also have shown that methods of application greatly affect yields. From all of these studies it has been concluded that the largest yields of crops in general would be obtained if the fertilizer, especially superphosphate, were placed close to the seed. (Other work at this Station has shown that the fertilizers and rates used in this test will not injure rice seed.) In view of these facts, work was started at the Beaumont Station in 1935 to compare the effect of broadcasting fertilizers on top of the soil and applying them in the drill with the seed. The treatments used and yields obtained are shown in Table 3. A combination of 150 pounds of sulfate of ammonia and 150 pounds of superphosphate per acre was the only fertilizer treatment used during the first two years as a preliminary trial. During this period the application of the fertilizer in the drill with the seed produced an average yield of 2,532 pounds of rice per acre, or about 11 per cent more than the appli- cation made on top of the soil. In view of these facts, with the fact that applications of superphosphate on top of the soil generally decreased the yield, two additional treatments, 150 pounds. of sulfate of ammonia and 150 pounds of superphosphate, were included in the test in later years. Superphosphate alone failed to materially increase the yield, as will be noticed in Table 3, when placed on top of the soil, or when placed in the drill with the seed. Sulfate of ammonia alone produced an increase of 346 pounds per acre when applied on top of the soil, but an additional 4 per cent increase was obtained by placing the fertilizer in the drill with ‘the seed. A combination of 150 pounds each of sulfate of ammonia and super- FERTILIZER FOR RICE IN TEXAS 11 phosphate drilled in With the seed made the highest average yield, 2,841 pounds of rice per acre, which was 12.6 per cent more than the yield from the same fertilizers applied on top of the soil. Although the increases in yield produced by putting the fertilizers in the drill with the seed are not very much larger than when they are broad- cast on top of the soil, they represent additional profit. This method is no more expensive than broadcast applications. These results indicate that drilling these fertilizers in With the seed is a better practice than broadcasting on top of the soil. Table 3. Acre yields of rice from broadcasting and drilling the fertilizer in with the seed Fertilizer treatment Method of application Increase by drilling in with seed Lbs. Broadcast Drilled in per Material on top of with the acre the soil seed Pounds Per cent No treatment . . . . . . . . . . . . . . . . . . 2176 2176 . . . . . . . . . . . . . . . . . . . . . . . . 160 Superphosphate . . . . . . . . . . . . . . . . 2181 2209 28 1.3 150 Sulfate of ammonia . . . . . . . . . . . . . 2522 2623 101 4.0 150 Superphosp hate 150 Sulfate of ammonia . . . . . . . . . . .. 2522 2841 319 12.6 Figure 2. Methods of applying fertilizers to rice.. Left, sulfate of ammonia applied in the drill with seed. Right, sulfate of ammonia and superphosphate applied in drill with seed. Addition of superphosphate to sulfate of ammonia makes practically no difference in growth when broadcast on top of soil. 12 BULLETIN NO. 602, TEXAS AGRICULTURAL EXPERIMENT STATION Comparison of Different Nitrogenous and Phosphatic Materials Cottonseed meal and manure as sources of nitrogen, along with sulfate of ammonia, were used in the fertilizer work during the first years of the fertilizer tests at Beaumont, 1915 to 1923. They were discarded after a few years because they did not give as satisfactory results as sulfate of ammonia, as shown in Bulletin 398. Superphosphate was used as the only source of phosphoric acid in the experiments until 1936. At that time it was decided to compare several forms of both nitrogen and phosphoric acid as fertilizers for rice. Sulfate of ammonia, nitrate of soda, and cyanamid comprised the nitrogenous materials during the first two years, but granular sulfate of ammonia and uramon were included during the latter part of the test. Both the regular and granular forms of superphosphate and raw bone meal were used to supply phosphoric acid in 1936, soft phos- phate with colloidal clay being included in the last four years. All nitrogenous materials were applied in amounts to supply 20 pounds of nitrogen per acre. The various phosphatic materials also supplied 2O pounds of phosphoric acid per acre. All fertilizers were applied in the drill with the seed with the exception of cyanamid which was (lrilled in just prior to seeding to prevent injury to the seed. The materials used and the yields of rice obtained from 1936 to 1940 are shown in Table 4. The results show very little, if any, difference in value between the nitrogenous materials. Cyanamid produced a slightly smaller yield of rice, but this was probably caused by this fertilizer having to be placed in the soil in such manner as to prevent its injuring the seed and, naturally, being further from the seed than was the case with the other materials. The comparable yields show a combination of sulfate of ammonia and Table 4. Acre yields of rice from different nitrogenous and phosphatic materials Yield in pounds Compar- Materials able 1936 1937 1938 1939 1940 Aver- yield age No fertilizer . . . . . . . . . . . . . . . . . . 2366 2188 1976 2069 2475 2215 2215 Nitrogenous materials: ‘ Sulfate ammonia (granular). . . . . . . . . . . . . . . . . . 3060 2469 3238 2922 2758 Nitrate of soda . . . . . . . . . . . . . 2356 . . . . . . . . 3322 2288 3131 2774 2706 Sulfate ammonia (regular). . . 2331 2419 3214 2275 3296 2707 2707 Uramon . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2350 3218 2784 2695 Cyanamid . . . . . . . . . . . . . . . . . . . . . . . . . . 2388 . . . . . . . . 2288 2632 2436 2466 Sulfate ammonia and nitrate of soda . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3432 3432 2906 Phosphatic materials: Bone meal . . . . . . . . . . . . . . . . . 2494 2519 3098 2656 3184 2790 2790 Superphosphate (regular) . . . . 2497 2362 3154 2394 3312 2744 2744 Superphosphate (granular) . . . 2522 2344 3214 2275 3296 2730 2730 Soft phosphate with colloidal clay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2319 2535 2431 3015 2575 2529 Superphosphate and bone meal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3246 3246 2750 FERTILIZER FOR RICE IN TEXAS 13 Figure 3. Sources of nitrogen and phosphoric acid for rice. Right, nitrogen from a combination of sulfate of ammonia and nitrate of soda. Left, received no fertilizer. nitrate of soda to be slightly superior to any one material alone, but as this treatment appeared in the test but one year it is doubtful if this is a significant difference. The results indicate that soft phosphate with colloidal clay is less valuable than the other phosphatic materials. The two superphosphates produced yields that were approximately equal, with bone meal producing a slightly larger amount of rice. Cooperative Tests The results of the fertilizer work conducted on the Lake Charles and Crowley soils on the Experiment Station farm at Beaumont have shown rather conclusively that the use of 100 to 200 pounds per acre of sulfate of ammonia alone or with superphosphate has given consistently good results under the particular conditions. Because the soils in other parts of the rice area vary considerably with respect to type, fertility, manage- ment, and length of time in cultivation, it may be possible that the results obtained at the Beaumont station are not applicable to all of the soils of the area. In order to get specific information on the fertilizer needs of the soils in other localities cooperative tests were conducted with several rice growers located on representative rice soils. These tests have been con- ducted in Jefferson County near Nome, near Devers in Liberty County, and in Grange County. 14 BULLETIN NO. 602, TEXAS AGRICULTURAL EXPERIMENT STATION Tests Near Nome Results of the tests near Nome are similar to those obtained in the work on the Experiment Station. Phosphoric acid alone produced only a slight increase in the yield of rice. Nitrogen alone produced an increase in yield of 326 pounds per acre. A combination of nitrogen and phosphoric acid increased the yield 377 pounds per acre above that of the unfertilized soil. The addition of potash to the nitrogen and phosphoric acid produced the heaviest yield, 2,722 pounds of rice per acre, or 421 pounds more than the unfertilized plats. Table 5. Cooperative test at Nome Acre yield of rice, pounds Per cent increase Treatment over 1935 1936 1937 1938 1939 1940 Aver- unfer- age tilized N0 fertilizer . . . . . . . . . . . . . . . . . . . . . . 1625 1669 2614 1990 3213 2696 2301 . . . . . . . . . . Nitrogen alone . . . . . . . . . . . . . . . . . . . 2010 1753 2913 2604 3532 2950 2627 14.2 Phosphoric acid alone . . . . . . . . . . . . . 1655 1669 2695 2280 3403 2808 2418 5.1 Phosphoric acid and nitrogen . . . . . . . 1932 1736 2988 2561 3677 3173 2678 16.4 Phosphoric acid, nitrogen and potash 1986 1896 3165 2508 3587 3193 2722 18.3 Tests in Liberty County The yields obtained in the tests near Nome are recorded in Table 6 and show that phosphoric acid alone was very beneficial on new land, but of doubtful value on old land. Nitrogen alone was of very little value in either case. A combination of nitrogen and phosphoric acid was superior to either alone during both years. Potash was not very effective on these soils. However, a combination of nitrogen, phosphoric acid, and potash made the largest average yield, 3,561. pounds of rough rice per acre for the three years, or 610 pounds more than the untreated soil. Table 6. Cooperative tests in Liberty County Acre yield rice, pounds % increase Treatment over 1935 1938 1940 Average unfertilized No fertilizer . . . . . . . . . . . . . . . . . . . . . . . 2109 3321 3422 2951 . . . . . . . . . . . . Nitrogen alone . . . . . . . . . . . . . . . . . . . . . 2163 3472 3530 3055 3 . 5 Phosphoric acid alone . . . . . . . . . . . . . . 3059 3041 3722 3274 10.9 Nitrogen and phosphoric acid . . . . . . . . 3190 3474 3862 3509 18.9 Nitrogen, phosphoric acid, and potash. 3156 3480 4048 3561 20. 7 FERTILIZER FOR RICE IN TEXAS 15 Tests in Orange County Table No. 7 records the results obtained in Orange County. Nitrogen alone was of very little value. Phosphoric acid alone increased the yield of rice 1,020 pounds per acre, or 43 per cent. A combination of nitrogen and phosphoric acid increased the yield 1,204 pounds per acre, or 50.7 per cent, over that of-the unfertilized soil. The heaviest yield, however, was obtained from the treatment that included nitrogen, phos- phoric acid, and potash. This application produced 3,602 pounds of rice per acre, or 1,228 pounds more than was obtained from the plats receiving no fertilizer. Table 7. Cooperative tests in Orange County Acre yield rice, pounds % increase Treatment over 1939 1940 Average unfertilized No fertilizer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2558 2191 2374 . . . . . . . . . . . . Nitrogen alone, . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2686 2339 2512 5.8 Phosphoric acid alone . . . . . . . . . . . . . . . . . . . . . . . .. 3796 2993 3394 43.0 Nitrogen and phosphoric acid . . . . . . . . . . . . . . . . .. 4143 3013 3578 50.7 Nitrogen, phosphoric acid, and potash . . . . . . . . . . . 4365 2838 3602 51.7 Figure 4. Cooperative test in Orange County. Left center reecived no fertilizer. Right center received superphosphate. Extreme right shows part of plat receiving sulfate of ammonia. 16 BULLETIN NO. 602, TEXAS AGRICULTURAL EXPERIMENT STATION Work with Manganese, Copper, Zinc, Iron, and Boron Some of the fertilizer work conducted on other crops in some cases has shown a deficiency of one or more of the so-called minor elements. It was considered doubtful that the yields of rice in Texas were being affected by a lack of any of these elements. However, in order to obtain some pre- liminary information on the possibility of the need of such investigations on the rice soils of the state, the cooperative tests were enlarged to include one treatment that contained several of the elements thought most likely to be deficient. In this work 500 pounds per acre of 4-8-4 fertilizer was used with and without manganese, copper, zinc, iron, and boron. The manganese was supplied in 20 pounds of potassium permanganate; copper, in 10 pounds of copper sulfate; zinc, in 20 pounds of zinc oxide; iron, in 50 pounds of ferric sulfate; and boron, in 10 pounds of boric acid. Boric acid was used at the rate of 20 pounds per acre in 1938, but appeared to have resulted in slight injury to the seed. The average yields of rice from the use of the complete fertilizer with and without the other elements are given in Table 8. The use of these additional elements has resulted in a decrease in yield each year in the tests in Liberty County, but probably did not affect the yields at the other locations. Table 8. Yields in pounds of rice per acre from the use of minor elements (Iron, Manganese, Copper, Zinc, and Boron) Without With Location of test minor minor elements elements Liberty County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3764 3337 Nome, Jefferson County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 3096 3278 Experiment Station, Beaumont . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2208 2148 Orange County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3602 3588 Average . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3168 3088 Acknowledgments The Texas Public Service Company of Beaumont, the Devers Canal Com- pany of Devers, the Croak Brothers of Orange, and Mr. Hugh Long, Jr., of Beaumont furnished the seed, land, and water for the cooperative tests conducted on their farms. In addition, they furnished all labor necessary excepting for planting and harvesting of the tests. FERTILIZER FOR RICE 1N TEXAS 17 Summary The rice fertilizer work has shown that the soils on the Rice Station at Beaumont respond to nitrogen and that the yields increase as the amount of fertilizer is increased. The use of 50 pounds of sulfate of ammonia‘ per acre increased the yield of rice 116 pounds, and the heaviest rate of sulfate of ammonia, 200 pounds per acre, produced the largest yield, which was 544 pounds more than was obtained from the unfertilized soil. These soils do not respond to phosphoric acid alone, but a combination of nitrogen and phosphoric acid was superior to nitrogen alone during the latter part of the test. There was a difference in the response of the soils in the various localities to the application of fertilizers to rice. Nitrogen alone produced practically no increase in yield of rice on the soils tried in Liberty county. Phosphoric acid alone increased the yield only 323 pounds per acre for the three years. However, it did increase the yield 950 pounds per acre in 1935 when used on a soil that was being cropped to rice for only the second time. A com- bination of nitrogen and phosphoric acid produced an increase in yield of rice of 558 pounds per acre in these tests. The use of phosphoric acid alone in the Orange county tests increased the yield of rice 1,020 pounds per acre. The soils tested in this county did not respond to nitrogen alone, and only a slight response was obtained by using it in combination with phosphoric acid. The use of fertilizers on the soils tested near Nome, in Jefferson county, produced results very similar to those obtained on the Station at Beaumont. The results obtained indicate there is no need of potash being included at this time in the fertilizers for rice on the soils tested. When the fertilizer was drilled in with the seed it gave a larger yield of rice and resulted in less growth of Weeds and grass than when it was broadcast on top of the soil. In comparing the two methods of applying fertilizers to rice on the Station soils, the largest yield, 2,841 pounds of rice per acre, was obtained from a combination of nitrogen and phos- phoric acid drilled in with the seed. This was an increase of 319 pounds over the yield obtained by the same fertilizer applied broadcast on top of the soil. Nitrate of soda, uramon, and regular and granular sulfate of ammonia are of practically the same value as sources of nitrogen for rice on the Station soils. Cyanamid was of less value as it could not be drilled in with "the seed on account of injury to the latter. A combination of sulfate of ammonia and nitrate of soda produced the largest yield obtained from any of the nitrogenous materials, but as this treatment was used only one year, this yield was not considered to be significantly larger than ‘the others. 18 BULLETIN NO. 602, TEXAS AGRICULTURAL EXPERIMENT STATION Bone meal and regular and granular superphosphate were of approxi- mately equal value as sources of phosphoric acid. Soft phosphate with colloidal clay was an inferior source of phosphoric acid on the Station soils. The results obtained from the use of iron, manganese, copper, zinc, and boron as fertilizers for rice will not justify their use for this purpose on the soils tested. The results as a whole show that a combination carrying 20 pounds of nitrogen and 20 pounds of phosphoric acid as would be supplied in 100 pounds each of sulfate of ammonia and superphosphate, per acre applied in the drill with the seed at planting time is good fertilizer practice on the principal rice soils of the area. LITERATURE CITED (1) Statistics of Texas Agriculture, L. P. Gabbard and C. A. Bonnen, Circular No. 80, page 22, Texas Agricultural Experiment Station, October, 1937. (2) Fertilizers for Rice in Texas, E. B. Reynolds and R. H. Wyche, Texas Agricultural Experiment Station Bulletin 398, June, 1929. (3) Varieties of Rice for Texas, R. H. Wyche and H. M. Beachell, Texas Agricultural Experiment Station Bulletin 485, November, 1933. (4) Rice Culture in the Southern States, Farmers’ Bulletin 1808, Jenkin W. Jones, J. Mitch- ell Jenkins, R. H. Wyche, and Martin Nelson, October, 1938.