bluuebunny/crossref_metadata_2025_split huggingface dataset:
Economic Interpretations of Yield Data from a Nitrogen Rate Experiment with Irrigated Grain Sorghum
Authors: Paschal J. L. , Evans C. E. 
Published: July 2010

AbstractYield data from a nitrogen rate experiment with grain sorghum on newly developed irrigated land at Tucumcari, N. Mex., were analyzed to ascertain the most profitable rate of nitrogen application for each of four treatment combinations of moisture and plant spacing. The principle of diminishing yield increments is used in calculating the most profitable rate.As the response of crops to nitrogen is known to vary with soil, season, and other environmental factors, the economic interpretations developed herein are intended to apply only to the conditions of this experiment. With the price of sorghum at $1.12 a bushel and the price of nitrogen at 15 cents a pound, the most profitable rate of nitrogen application ranges from 75 to 152 pounds per acre. The most profitable rate is highest with high moisture (8 irrigations) and thick spacing (43,560 plants per acre) and lowest with low moisture (5 irrigations) and thin spacing (20,028 plants per acre). Moisture level influences the most profitable rate of nitrogen application more than does plant population. When nitrogen is applied at its most profitable rate, the return to nitrogen above its cost with high moisture is $33 for thick and $11 per acre for thin spacing. With low moisture, the return is $15 and $19 per acre for thick and thin spacing, respectively.The most profitable rate of nitrogen application and necessarily the return to nitrogen above its cost at this rate depend also on the price of sorghum a bushel and the price of nitrogen a pound. Under conditions of constant price and application rate of nitrogen, returns are directly proportional to the price of sorghum. As the price of sorghum rises, the most profitable rate of nitrogen application rises at a decreasing rate. Unless the rate is adjusted with changes in the price of sorghum, loss in return to nitrogen above its cost will result. In most instances, variations of 28 cents a bushel in the price of sorghum above 84 cents affect the most profitable rate of nitrogen application by 25 pounds or less per acre. Exclusive of the direct effect of a change in the price of sorghum on return, failure to apply the most profitable rate when the price changes by $0.28 a bushel results in a loss in returns of $1.00 or less per acre for each moisture‐plant spacing treatment.With the price of sorghum constant at $1.12 a bushel, moderate changes in the price of nitrogen do not greatly affect either the most profitable rate of application or the return to nitrogen. The rate changes 21 pounds or less with a change of 3 cents a pound in the price of nitrogen for 3 of 4 moisture‐plant spacing treatments. With a change of a cent a pound, return to nitrogen above its cost varies about $1 an acre or less for low‐moisture treatments and less than $2 an acre for high‐moisture treatments.
Soil Organic Matter Levels and Crop Yields in Puerto Rico
Authors: Lugo‐López M. A. , Bonnet J. A. , Hernández‐Medina E. , Landrau P. , Samuels G. 
Published: July 2010

AbstractNo increases in organic‐matter content were observed in some latosols of Puerto Rico with an open porous structure and low fertility level when treated with different quantities of velvetbean green manure, sugarcane trash, and filter‐press cake. Increased yields of corn were obtained only when the soil was treated with velvet bean green manure, probably because of increased nitrogen supply.Definite increases in organic‐matter content were obtained with the above treatments in heavy‐textured nonlateritic soils of moderate fertility, but unfavorable physical conditions. In this case, increased yields of sugarcane and pineapple were obtained probably due to the favorable effect of increased amounts of organic matter on the physical conditions of the soils. The seven field experiments reported here have been established for relative short periods only, not over 7 years, but some of them are scheduled for long‐time duration.
Effects of Long‐Time Soil Treatments on Some Physical Properties of Several Illinois Soils
Authors: Gingrich Joe R. , Stauffer R. S. 
Published: July 2010

AbstractSoil cores, 2 inches in diameter and either 1⅜ or 1½ inches in length, were taken from 6 Illinois soil experiment fields in the late summer and fall of 1952 and from 1 field in the early spring of 1953 to study long‐time effects of 3 different soil treatments on permeability to water, moisture percentages at one‐third and at 15 atm. pressures, bulk density, non‐capillary pore space, and the maximum water available for plant growth. All laboratory determinations were made on the undisturbed soil core except the 15 atm. moisture percentages which were made after drying and breaking up the soil core. The treatments studied were manure, limestone, and rock phosphate; no treatment; and crop residues, limestone, rock phosphate, and potash. These systems of management have been followed for approximately 40 years at all locations.The mean values for several determinations differ greatly for the three treatments but in only a few cases are the differences statistically significant. The manure, limestone, and rock phosphate treatment was usually the most favorable treatment when significant differences were found.In the design of the experiment fields, replication and crop are confounded. The only mean square for testing treatments was the crop x treatment interaction which was usually large and had only 4 degrees of freedom. This may be the reason why more differences due to treatment were not shown to be significant.
Influence of Sample Pretreatment on Soil Moisture Retention
Authors: Elrick D. E. , Tanner C. B. 
Published: July 2010

AbstractThe effect of sample pretreatment on soil‐moisture retention was measured on eight Wisconsin soils to find the moisture tension range in which undisrupted soil samples are necessary to represent the moisture relations of field soils. The moisture retention of samples with pretreatments either of 2‐mm. sieving or puddling was compared with the retention of undisrupted cores over the moisture tension range of 0.01 to 15 atm.In general, the moisture retention of sieved samples of the medium textured soils studied was increased over core samples at tensions less than 0.4 atm. There was no general relationship in the tension range of 0.4 to 1.0 atm. because of the irregular nature of the release curves of individual soils. Sieving decreased moisture retention about 1 part in 10 at tensions greater than 1.0 atm. Thus sieved samples of the medium textured soils studied can be used to approximate undisrupted soils in the high tension range with a relative error of 10%. Core samples should be used at tensions less than 1.0 atm. to avoid relative errors greater than 10% (up to 30%).Puddled samples retained considerably more water than cores in the tension range from 0.1 to 2.0 atm. although they differed little from core samples at tensions less than 0.05 to 0.1 atm. and greater than 5.0 atm. Puddled soils give a better approximation of undisrupted soils than sieved soils at tensions between 5 and 15 atm.
Radioactive Studies with P32 in Tropical Soils and Crops of Puerto Rico
Authors: Bonnet J. A. , Riera A. R. , Roldán J. 
Published: July 2010

AbstractSix experiments—three with sugarcane, one with pineapples, and two with coffee—were completed with P32 to determine what percentage of the phosphorus was taken by the crop from the fertilizer and from the soil respectively. Five different methods of applying the fertilizer to coffee trees were also studied. Superphosphate tagged with P32 was used. The contents of total P and P32 in the crop leaves served as an index for this work.The data and results obtained in the sixth experiment, the second with coffee, are presented here. A second objective of the experiment was to determine if the leguminous trees, that serve as shade to the coffee trees, absorb part of the phosphorus added as a fertilizer.The results obtained indicate that coffee trees absorbed a highly significantly greater percentage of the phosphorus from the fertilizer when it was broadcast over the whole or over a 2‐foot wide outer segment of the canopy area than when it was applied in bands, in holes, or over the terrace.The results indicate also that the leguminous shade trees absorb part of the phosphorus applied to the coffee trees.
“Brown Mud” from the Aluminum Industry as a Soil Liming Material
Authors: Whittaker Colin W. , Armiger W. H. , Chichilo P. P. , Hoffman W. M. 
Published: July 2010

Abstract“Brown mud” is a siliceous waste product resulting from the extraction of alumina from bauxite. Present production is estimated to exceed half a million tons annually, the disposal of which is a problem in the industry. When dry, the mud contains approximately SiO2 23, CaO 47, Fe2O3 10, TiO2 3.5, Al2O3 5.5, and Na2O 3.6%, and small amounts of other elements.In a greenhouse study with sweetclover as the indicator crop, using acid Evesboro and Chester soils, the dried brown mud produced yields substantially equal to those obtained with equivalent amounts of other liming materials. Emergence counts and appearance of the crop gave no indications of any toxic effects from the use of the mud. The mud increased soil pH to values that were usually equal to or exceeding those produced by finely divided agricultural limestone and were sometimes equal to those produced with hydrated lime. The calcium concentration in the dried plant material increased as the liming rate increased in about the same manner with the mud as with the other liming materials. As might be expected, the sodium content of the crop tended to be higher where the mud was used. The potassium content of the crop was reduced to a greater extent by the mud than by either hydrated lime or limestone: this effect was probably also due to the sodium content of the mud. The data indicate that the dried mud is a satisfactory liming material.
A Chemical Method for the Rating of Agricultural Limestones Used as Soil Amendments
Authors: Gibaly Hilmy El , Axley J. H. 
Published: July 2010

AbstractA method for the calibration of the efficiency of both calcitic and dolomitic limestone in relation to their rapidity in correcting acidity in soils is proposed. The procedure is as follows:Exactly 1.0 gm. of the limestone to be tested is added to 250 ml. of boiling 0.07 N disodium ethylene‐diaminetetraacetate which is contained in a 500‐ml. Erlenmeyer flask connected to a reflux condenser. After refluxing 20 minutes, 10 ml. of ammonia buffer solution (pH 10) is rapidly added. The solution is immediately titrated with 1.0 N magnesium sulphate solution using Eriochrome black T as indicator. The end point is attained when the color of the indicator changes from blue to wine red. Time and rate of heating must be controlled precisely.Limestone samples are calibrated from these titration results by comparing them to the reaction of calcite under identical conditions.When the results of this test for 19 commercial limestone samples were compared with the pH change of soil suspensions treated with the same materials, a correlation of 0.96 was obtained. A field test of nine commercial samples showed a correlation with this test of 0.79.
Laboratory, Greenhouse, and Field Studies With Mixed Fertilizers Varying in Water‐Soluble Phosphorus Content and Particle Size
Authors: Owens L. , Lawton K. , Robertson L. S. , Apostolakis C. 
Published: July 2010

AbstractGreenhouse and field studies were undertaken to evaluate the effect of the water‐soluble phosphorus content and particle size of mixed fertilizers on the availability of fertilizer phosphorus to plants. Supplementary laboratory experiments were conducted to study the behavior of phosphorus in granulated mixed fertilizers under various soil conditions.The rate at which the water‐soluble fraction of phosphorus moved out of fertilizer granules was rapid, essentially being complete in 48 hours. No important difference in dissolution rate was noted for fertilizers with varying water‐soluble phosphorus contents over the range of 3.3 to 15% moisture. The extent of movement of fertilizer phosphorus away from large granules and the concentration in soil around the phosphate was directly related to the percentage of water‐soluble phosphorus in the fertilizer.Varying the water‐solubility of phosphate fertilizer having a similar N‐P2O5‐K2O ratio had no significant effect on dry weight yield of wheat plants grown in the greenhouse. The percentage of plant phosphorus derived from fertilizer was markedly influenced by the water‐soluble phosphorus content and the particle size of the mixed fertilizer and soil reaction. Absorption of fertilizer phosphorus by wheat plants from 4–6 mesh granular material was directly proportional to its water soluble phosphorus content. For pulverant fertilizers the phosphorus water solubility had very little effect on the percentage of plant phosphorus derived from fertilizer. At a soil pH of 5.5, wheat absorbed a larger quantity of fertilizer phosphorus than when grown at pH 6.5 or 7.5.The phosphorus content of field grown sugar beet plants was significantly higher 1 month after planting on plots where fertilizers high in water‐soluble phosphorus were used as compared to those from plots treated with fertilizers low in water‐soluble phosphorus. Two months after planting, values for total phosphorus were similar for plant samples from plots receiving fertilizers either high or low in water‐soluble phosphorus. Although the yield response to phosphorus was highly significant, there were no significant differences in sugar beet yields between fertilizer treatments.
Crop Rotations and Soil Nitrogen
Authors: Haynes J. L. , Thatcher L. E. 
Published: July 2010

AbstractEvidence from a 39‐year record of corn yield from trop rotation experiments on Wooster silt loam soil fails to show long‐term cumulative trend effects of commonly‐used corn belt rotations on soil productivity. Yield levels characteristic of a given rotation were quickly reached with no pronounced trends thereafter. In general, yield level was associated with soil nitrogen level. Long‐term downward trends in apparent soil productivity level were observed under conditions of continuous cropping to corn and under conditions of severe erosion.
Effects of Cultivation on Some Soil Physical Properties and on Potato and Corn Yields
Authors: Blake G. R. , Aldrich R. J. 
Published: July 2010

AbstractField corn and potatoes were cultivated 0 to 3 times and 0 to 5 or 7, respectively for 3 years, to determine the best level of cultivation for each crop. Weeds were controlled with chemicals so that the noncultivated plots were neither hoed nor scraped. One cultivation for corn or one or two for potatoes gave virtually as high yields as any greater number. All amounts of cultivation gave higher yields than none at all.Excessive cultivation resulted in lower air space and aggregation and higher bulk density though these differences were not always significant. Cultivation and sprayer traffic was shown to result in a generally lower potassium content of potato leaves. This is believed related to the lower air space found under these conditions.Soil moisture tensions show that some of the benefit from cultivation may result from conservation of moisture. They also indicate that while weeds compete for moisture, this alone does not account for higher yields where weeds are controlled by cultivation.
A Tube Containing Gypsum Blocks for Following Moisture Changes in Undisturbed Soil
Authors: Abd‐El‐Samie Ahmed G. , Marsh Albert W. 
Published: July 2010

AbstractThe increased use of gypsum blocks for following soil moisture changes and scheduling irrigations has stimulated efforts to improve their installation, performance, and removal from the field. Gypsum blocks were cast in tubes at 6‐inch intervals to simulate the usual practice of installing a series of blocks through the root zone. Three types of block‐in‐tube constructions were described and results from their use reported. The results indicate that blocks perform satisfactorily when cast in tubes.The tubes can be quickly installed in an auger or king tube hole, assuring intimate contact with undisturbed soil and roots. The problems associated with back‐fill are eliminated and removal at the close of the season is easy. The length of time following installation for equilibrium with the surrounding soil to be reached is reduced.
Rock Phosphate Availability as Influenced by Soil pH
Authors: Ellis Roscoe , Quader M. A. , Truog Emil 
Published: July 2010

AbstractThe influence of the pH of the culture medium on the availability of rock phosphate to oats was investigated by means of two sets of pot cultures. In one set, quartz sand containing 1% of montmorillonite clay served as the culture medium. Samples of the clay, previously saturated with H+, were treated with varying amounts of Ca(OH)2 to provide a series of samples having pH values of 4.9, 5.5, 6.2, 6.7, and 7.4, respectively. Addition of these clays to quartz cultures imparted their respective pH's to the cultures. In one series, rock phosphate served as a source of phosphorus, and in a second, superphosphate served similarly. All other nutrients were supplied in soluble forms. The yield with rock phosphate was highest at pH 5.5. With superphosphate yields were good throughout and approximately double those with rock phosphate. A soil pH of 6.0 or lower appears to be necessary for satisfactory utilization of rock phosphate.In a second set of pot cultures, Spencer silt loam subsoil of pH 5.1 and very low in organic matter and available phosphorus served as the culture medium. Other nutrients than phosphorus were supplied in available forms. When rock phosphate was applied 1 month prior to liming to pH 7, the oats grew much better and absorbed much more phosphorus than when the order of applications was reversed, showing that strongly acid soils act on rock phosphate rather rapidly, and that for rock phosphate to be effective acidity is needed. Thus, it is advisable to apply rock phosphate a year or more in advance of liming.
Brunizem‐Gray Brown Podzolic Soil Biosequences
Authors: White Everett M. , Riecken F. F. 
Published: July 2010

AbstractA study was made of two biosequences composed of Brunizem and Gray Brown Podzolic soils and their forested intergrades to determine some of the properties of the intergrades and their relationship to recognized great soil groups. The morphology of the intergrade soils is intermediate to that of the associated Brunizems and Gray Brown Podzolic soils. Laboratory data indicate that, genetically, the intergrade soils are related more closely to the Gray Brown Podzolic soils than to the Brunizems.
The Interaction of Kind of Soil Colloid, Fertility Status, and Seasonal Weather Variation on the Cation Content of Turnip Leaves
Authors: Army T. J. , Miller E. V. 
Published: July 2010

AbstractIn a study of the effect of environmental factors on cation content of turnip greens, seasonal weather variations from spring to fall were shown to be of similar importance to soil and fertilizer factors.Divalent cation content of leaves was greater in spring than in fall. Monovalent cation content was significantly higher in the fall than in the spring.The magnitude of the seasonal effects on cation concentration was modified by the type of clay mineral predominating in the soil and by the percentage soil saturation with Ca and Mg.The critical level of divalent cation saturation was higher on montmorillonitic than kaolinitic soil. Evidence was obtained for a sharp increase in divalent ion availability between 66% and 76% divalent base saturation on the montmorillonitic soil. A higher lime level would be required in fall than in spring especially on montmorillonitic soils.
Copper Requirements and Deficiency Symptoms of a Number of Field and Vegetable Crops
Authors: Nelson L. G. , Berger K. C. , Andries H. J. 
Published: July 2010

AbstractA number of field and vegetable crops were grown in the field and greenhouse on a peat soil very deficient in copper. Yield responses and copper contents of the plants were determined and copper deficiency symptoms photographed and described.In another series of tests the need for copper by oats on a number of upland soils was determined, and data concerning yield and copper content of the oats are presented. Significant increases in yields of straw were obtained in several cases.In the tests on the peat soil, oats showed the greatest need for copper among field crops and red beets among vegetable crops. Oat yields without copper were slightly over 1 bushel per acre, and with copper 64 bushels. Red beet yields were increased 5‐fold by the application of copper to this soil. Copper contents of plants varied considerably and in general increased with copper fertilization.
Effect of Lime Application on Nutrient Uptake by Alfalfa
Authors: Thorp F. C. , Hobbs J. A. 
Published: July 2010

AbstractA greenhouse study was conducted at Kansas State College on some acid soils from the south‐central part of Kansas to determine the effect of lime application on the composition of alfalfa plants. Samples of surface soil, which ranged in reaction from pH 5.0 to 5.8, were limed to pH 6.3, 6.6, and 6.9. Yields of alfalfa were obtained, and the plant material analyzed for calcium, magnesium, phosphorus, and potassium.Lime applications significantly increased the calcium percentage in the plants. Total uptake of calcium by alfalfa was increased also by lime applications. No significant differences in percentage of magnesium or total magnesium uptake resulted from liming. Applications of lime had no apparent effect on the phosphorus percentage of the plant, but the uptake of phosphorus was greater from the limied than from the unlimed soils. Potash uptake was also increased by lime applications.
Peat Deposits of the State of Washington
Authors: Rigg George B. , Gessel Stanley P. 
Published: July 2010

AbstractThis paper emphasizes (1) the structure of the entire peat deposit down to clay, sand, or gravel, (2) the plants whose remains have formed the various kinds of peat, (3) the origin of the depressions in which the deposits have developed, and (4) the physical and chemical properties of the peat.The 325 deposits which were investigated comprise over 50,000 acres and vary in depth from 3 to 63 feet. The kinds of peat in the order in which they commonly occur from top to bottom and the plants from whose remains they were formed are (1) moss peat from various species of Sphagnum, (2) fibrous peat mostly from sedges, (3) woody peat from logs, twigs and leaves, and (4) sedimentary peat frommicroscopic plants. Moss peat is absent in many deposits. The asociated mineral materials are mostly marl, diatomite (diatomaceous earth), and volcanic ash.The depressions in which the deposits have developed were formed mainly by the activities of ice, water, or wind. A summary of the ranges and averages of pH, field moisture, ash, chemical composition and replaceable bases is tabulated. The types of soil on the deposits are Greenwood, Mukilteo, Spalding, Rifle, Tanwax, and Salt Marsh.Data on chemical composition of the peat, including replaceable bases are given.