bluuebunny/crossref_metadata_2025_split huggingface dataset:
Importance of Soil Organic and Inorganic Phosphorus to Plant Growth at Low and High Soil Temperatures
Authors: Eid M. T. , Black C. A. , Kempthorne O. 
Published: July 2010

AbstractThe plant‐available P in a group of soils was estimated at soil temperatures of 20° and 35° C on the assumption that the response to P obtained in a green‐house experiment followed the Mitscherlich law. By multiple linear regression the dependence of the plant‐available P on the following soil P fractions was calculated: (1) inorganic P soluble in a solution 0.03 N to NH4F and 0.025 N to HCl; (2) organic P soluble in hot 1% K2CO3 and hydrolyzed by KOBr; (3) organic P soluble in hot 1% K2CO3 and not hydrolyzed by KOBr; and (4) organic P not soluble in hot 1% K2CO3. At 20° C the plant‐available soil P was determined by inorganic fraction 1. Organic fraction 2 had no appreciable effect. At 35° C the plant‐available soil P was determined by both inorganic fraction 1 and organic fraction 2. Organic fractions 3 and 4 were of no importance at either temperature. A probable cause of the observed results is that at 20° C the rate of organic P mineralization was low and the plant was dependent on inorganic fraction 1 originally present. At 30° C the plant was supplied with inorganic fraction 1 plus additional inorganic P from the mineralization of organic fraction 2.
Soil Hardness Measurements in Relation to Soil Moisture Content and Porosity
Authors: Jamison V. C. , Weaver H. A. 
Published: July 2010

AbstractA method of adjusting penetrometer measurements so as to express soil porosity conditions is presented. The best simple function giving high correlations with macroporosity in the Decatur clay and the sandy clay subsoil of Greenville fine sandy loam was log (ϑH1/2) where ϑ was field moisture percentage and H the hammer blows required to cut a soil core. The hardness function can be used to estimate macroporosity and compares favorably with the latter in relationship to depth of rooting, growth, and height of cotton plants.
Weight and Nitrogen and Calcium Content of the Annual Litter Fall of Forests in the South Carolina Piedmont
Authors: Metz Louis J. 
Published: July 2010

AbstractThe annual fall of litter was measured in stands of pine, mixed pine‐hardwood, and hardwood in the South Carolina Piedmont. The total amount of litter (including twigs, bark, and fruit) dropped annually ranged from 4,059 to 5,619 pounds per acre on an oven‐dry basis. Considering leaf fall alone, the annual drop ranged from 2,938 pounds in a 30‐ to 40‐year old stand of shortleaf pine to 4,476 in a 25‐year old loblolly pine stand.The content of nitrogen, calcium, and magnesium in freshly fallen leaves was determined for 14 tree species. The foliage of both loblolly and shortleaf pines was found to contain less of these elements than any of the hardwood species. Based on these chemical determinations and the annual leaf fall, estimates are given of the total amount of these nutrients returned to the forest floor by the annual leaf fall in the nine stands studied. The hardwood stands were found to return about twice as much nitrogen, three times as much magnesium, and five times as much calcium in their leaf fall as did the pine stands. Information given as to the nutrient content of the common forest species and in the litter fall of representative stands can be used by the forester to evaluate the effect of his management practices upon soil conditions.
Lime Requirement Determination of Soils
Authors: Patel D. K. , Truog E. 
Published: July 2010

AbstractA method is proposed for determining the amount of lime needed under field conditions to bring acid soils to the neutral point. In this method a sample of soil is treated with a measured amount (always an excess) of standard calcium bicarbonate solution. After evaporation followed by wetting with water and a second evaporation, the excess of calcium bicarbonate which was added, now in the form of CaCO3, is determined by means of the Collins' Calcimeter. This instrument measures the CO2 evolved when the sample is treated with dilute HCl. From the volume of CO2 evolved, the excess of carbonate added and by difference the amount that reacted with the soil, the lime requirement, are calculated. The results obtained with several soils check closely with those obtained in field plot tests where varying amounts of lime were added.
Effect of Management on Soil Permeability
Authors: Van Doren C. A. , Klingebiel A. A. 
Published: July 2010

AbstractThe purpose of this study was to determine some changes that have taken place in the surface of cultivated soils. Permeability, volume weight, and percent of pores drained were determined on virgin soils, fertilized and unfertilized soils, soil farmed to a good rotation in contrast to a poor rotation, and eroded soils as compared to slightly eroded soils. Some studies were also made on the effect of cultivation on percent aggregation. Six different soils were studied in the state.Undisturbed core samples were taken at random with a steel cylindrical sampler and analyzed for permeability, volume weight, and pores drained. Most samples were taken from corn fields in the fall of the year.Infiltration values for soil with various mulch covers were secured in the field with a type F infiltrometer.The surface of most soils was originally moderate to moderately rapid in permeability. The addition of limestone and fertilizers has increased the permeability rate of the soil as compared to the untreated plots. This response may be attributed to increased growth of plants. The percentage of large aggregates (1.0 mm) in the surface soil of cultivated areas was reduced from 4 to 20 times as compared to virgin areas. Surface samples taken from plots farmed to a corn, oats, clover, wheat (clover) rotation were 16 times more permeable and held 17% more available water than samples taken from plots farmed to a corn, corn, corn, soybean rotation. Severely eroded soils were less permeable than moderately eroded soils. Wheat straw and crop residues increased infiltration rates approximately three times as compared to bare ground, no mulch.
Ion Activities in Sodium‐Clay Suspensions
Authors: Whitney Robert S. , Peech Michael 
Published: July 2010

AbstractA study has been made of dissociation and hydrolysis of Na‐clay as a function of the degree of Na+ saturation of the clay and the concentration of NaCl in the clay suspension. The activities of Na+, H+, HCO3‐, and Cl‐ in the clay suspension were measured by the Donnan equilibrium method. From the Donnan distribution of ions between the two phases, it has been possible to apportion the observed Na+ activity in the clay suspension to Na+ dissociated from the clay and to diffusible sodium salts present in the clay suspension. The activity of Na+ dissociated from the clay and the activity of Na+ due to the presence of diffusible sodium salts in the clay suspension were both found to increase with the increasing degree of Na+ saturation of the clay and increasing concentration of NaCl or Na‐clay in the clay suspension. The anomalous increase in the activity of Na+ dissociated from the clay with the increasing concentration of NaCl or Na‐clay in the suspension may be attributed to the decrease in the thickness of the ionic atmosphere around the clay particle, resulting in greater concentration of osmotically active Na+ ions in the outer part of the diffuse double layer.
Gray Wooded Soils in Parts of Alberta and Montana
Authors: Williams B. H. , Bowser W. Earl 
Published: July 2010

AbstractRecent field correlations, laboratory study, and a review of the literature on forested soils of the Northern Great Plains and contiguous mountainous areas and areas east of the plains indicate a need for pointing up the relationships among the several groups of podzolic soils of this region. To attain this objective the attention of the authors was focused on the analyses of field observations, field notes, and laboratory data pertaining to selected samples of Gray Wooded soils and some associated soils in Alberta and Montana. Differences and similarities among Gray Wooded soils and how they differ from the associated soils and from Podzol soils in eastern United States and Canada are brought out graphically and in discussion. Particular stress is placed on the climatic environment, natural vegetation, and parent materials that seem to account for the unique properties of these soils. Representative profiles of three Gray Wooded soils are described in detail.
The Effect of Sulfur Oxidation on the Availability of Manganese
Authors: Vavra Joseph P. , Frederick Lloyd R. 
Published: July 2010

AbstractThe purpose of this investigation was to determine the effect of bacterial oxidation of sulfur upon the release of soluble manganese from manganese dioxide. Using the soil perfusion technique it was found that the oxidation of elemental sulfur or sodium thiosulfate applied to soil resulted in a release of soluble manganese accompanied by a lowering of pH. Addition of calcium carbonate caused a decrease in the amount of soluble manganese released, although the amount of sulfate formed was not changed significantly. In pure culture studies on synthetic media, 10 times more soluble manganese was found when sulfur was oxidized by Thiobacillus thiooxidans than when the same acidity was produced by the addition of sulfuric acid. Separation of the MnO2 from the sulfur and the bacteria by a collodion membrane did not prevent the reduction of manganese.
A Theory on the Soil Atmosphere in and around a Hemisphere in Which Soil Gases Are Used or Released
Authors: van Bavel C. H. M. 
Published: July 2010

AbstractIf the root system of a plant is taken as approximately hemispherical it is of interest to compute the distribution of partial pressures of soil gases. This can be done by assuming that these gases are taken up, or released, at a constant rate throughout the hemisphere and also that the physical condition of the soil with regard to diffusion is uniform.Inside the hemisphere the solution is a simple algebraic expression and outside it is an infinite series containing Legendre's polynomials. In addition to the exact formulas the solution is given in the form of a computed graph, which may be used to calculate actual values of partial pressure at any point in the soil, if the necessary constants are known. It appears that the extreme values of partial pressure are closely centered around the apex of the hemisphere.
Yield and Quality of Peas for Processing as Affected by Lime and Fertilizers
Authors: Terman G. L. , Murphy H. J. 
Published: July 2010

AbstractIn order to obtain information which might improve yields, lime and fertilizer tests on peas for canning and freezing were conducted in Aroostook County and central Maine over a 4‐year period, 1947–1950.Applying 300–400 pounds of finely ground dolomitic limestone down the drill spout with the pea seed increased the yield of shelled peas on the average by 645 pounds per acre on acid potato soils. With properly inoculated seed lime applications prevented premature yellowing of the vines and resulted in norinal dark green growth of vines without nitrogen fertilization of the crop.Where lime was applied with inoculated seed, application of N or NPK fertilizers resulted in increases in yields of shelled peas of low tenderometer ratings and high quality in only 4 out of 16 experiments. Yields of vines, however, were increased consistently by N fertilization; in most experiments yields of shelled peas of high tenderometer ratings and low quality were also increased. With peas harvested on the same day both lime and nitrogen tended to delay maturity, as shown by lower tenderometer ratings.Since lime and nitrogen have similar effects on yields of peas grown on acid soils, it may be concluded from this study that application of lower costing lime with inoculated pea seed is more profitable than higher costing nitrogen fertilization. Application of nitrogen can usually be justified only to delay maturity of part or all of the crop to facilitate harvesting a high quality pack. Application of P and K fertilizers is recommended only as insurance on soils testing low in these nutrients.
The Potassium Supplying Power of Representative Arkansas Soils
Authors: Legg J. O. , Beacher R. L. 
Published: July 2010

AbstractAn evaluation of the potassium supplying power of soils, including both exchangeable and moderately available potassium, is of particular importance in predicting potash fertilizer needs for permanent pastures.Greenhouse tests were conducted with 12 soils to measure the response of Ladino clover and common ryegrass mixtures to potash fertilization (100 pounds K2O per acre), other nutrients being supplied as needed. Laboratory data are presented to compare the plant growth response to potash fertilization with the general chemical nature of the soil exchange complex and the amounts of potassium extracted by normal nitric acid, sodium acetate, neutral ammonium acetate, and successive leachings with saturated carbonic acid.All soils were considered low to moderately low in available potassium, ranging from 43 to 125 ppm exchangeable K and from 1.0% to 5.5% exchangeable potassium saturation. The amounts of potassium solubilized by boiling the soil in normal nitric acid were above 250 ppm in soils which did not respond to potash fertilization, and below 250 ppm in five soils in which plant growth was significantly increased by potash treatments. Two very sandy soils with less than 80 ppm of nitric acid‐extractable K and approximately 5.0% exchangeable potassium saturation did not respond to potash fertilization. Lespedeza did not respond significantly to a field potash application on a sandy soil low in exchangeable potassium.Results suggest that favorable response to potash fertilization may be expected on soils with exchange capacities above 5 me/100 gm. and nitric acid‐extractable potassium levels below 250 ppm K, providing other nutrients are adequate. The amounts of potassium extracted by carbonic acid, neutral ammonium acetate, or sodium acetate (pH 4.8) were not sufficiently indicative of the potassium supplying power of these soils to be solely used as a sound basis in predicting the need of potash fertilization.
The Effect of Inoculation upon Yields of Soybeans on Treated and Untreated Soils
Authors: Lynch D. L. , Sears O. H. 
Published: July 2010

AbstractThis experiment was designed to evaluate the importance of inoculation of soybeans when grown on land where well‐nodulated soybeans had been grown previously. The effect of soil conditions, and of time interval following previous inoculation, upon response of soybeans to inoculation was observed.Neither soil treatment or interval of time since the host plant had been grown had any influence upon crop response to inoculation. Even on plots which had not grown soybeans since 1939, inoculation did not increase soybean yields. Although inoculated soybeans gave smaller yields than did the uninoculated in many cases, no significance was attached to this observation. Fields having a total nitrogen content of less than 3,000 pounds per acre gave a higher proportion of gains to losses than those containing more than this amount. Yields of both inoculated and uninoculated crops were greater on soils which had been treated with limestone, phosphate, and potash than on untreated check plots. It is concluded that inoculation should be practiced as an inexpensive insurance policy.
Correlation of Plant Tissue Tests of Corn, Deficiency Symptoms, and Soil Analyses on the Jordan Fertility Plots
Authors: Driskell B. N. , Richer A. C. 
Published: July 2010

AbstractAlthough soil tests, tissue tests, and visual deficiency symptoms have been used rather extensively by many agronomists for the diagnosis of nutrient deficiencies existing in soils and plants, no comprehensive comparison of the interrelationship of those methods of diagnosis is available. Therefore, it was the purpose of this investigation to determine the correlation and relationship of these diagnostic methods to each other for nitrogen, phosphorus, potassium, and magnesium with corn as a test crop. The Jordan fertility plots served admirably as a source of material for such an investigation since they were established in 1881 and have attained stable fertility levels, depending upon the fertilizer treatment of each plot. Two corn hybrids (Ohio K‐24 and Ohio M‐15) were grown on each of the 36 plots on tier 1 in 1948 and again on tier 2 in 1949.The soils were analyzed for available nutrients according to standard accepted methods. Potassium and nitrogen tissue tests were made according to the descriptions of Richer2 and Kohnke3, respectively. The tissue test for phosphorus, as described by Kohnke3, was modified and a tissue test for magnesium was developed. Visual deficiency symptoms for nitrogen, phosphorus, potassium, and magnesium were evaluated on each plot for each of the two corn hybrids. The deficiency symptoms described by previous workers were found to be a reliable guide for distinguishing the plant nutrient deficiencies of nitrogen, phosphorus, potassium, and magnesium.When soil tests, tissue tests, and deficiency symptoms were compared on tiers 1 (unlimed) and 2 (limed) of the Jordan fertility plots with two corn hybrids (Ohio K‐24 and Ohio M‐15), the following conclusions appeared justified.Nitrogen. — An excellent correlation at the 0.1% level of significance was found between tissue tests and visual deficiency symptoms on tiers 1 and 2; however, no correlation was found between the tissue tests and potential nitrification of the soil or visual deficiency symptoms and potential nitrification of the soil.Phosphorus. — Highly significant correlations were found in all instances, namely, between (1) soil tests and tissue tests, (2) soil tests and deficiency symptoms, and (3) tissue tests and deficiency symptoms.Potassium. — All correlation coefficients were significant at the 0.1% level between exchangeable soil potassium and tissue tests, exchangeable soil potassium and deficiency symptoms, and tissue tests and deficiency symptoms.Magnesium. — The correlation coefficients between exchangeable magnesium and tissue tests on the limed tier were not significant at the 5% level but were significant on the acid tier. Significance at either the 1% or the 0.1% level was found between exchangeable soil magnesium versus deficiency symptoms and tissue tests versus deficiency symptoms.Good correlations were obtained in most instances between soil tests, tissue tests, and deficiency symptoms, but no one test is always conclusive.
Use of Soil Survey Information for Tax Assessment in Taylor County, Iowa
Authors: Scholtes W. H. , Riecken F. F. 
Published: July 2010

AbstractA detailed soil survey was utilized by the county assessor in Taylor County, Iowa for reassessment of rural land in 1949. Detailed information was provided on the soils and their relative productivity ratings according to their suitability for the production of corn. Dollar values were established by the assessor for the different corn suitability ratings. The values of the tracts for assessment were then simply obtained by adding the measured acreage of each soil in the tract times its dollar valuation, minus certain deductions for such factors as waste.
Further Trials with Intercropping of Corn in Established Sods
Authors: Kurtz Touby , Melsted S. W. , Bray R. H. , Breland H. L. 
Published: July 2010

AbstractThis paper reports a continuation of trials in which corn is grown in cultivated slits in previously established sods of several single grasses and legumes. An attempt was made to estimate the nitrogen needs of the corn under different intercrops and to determine which intercrops were most adaptable and desirable in this system. Some data on soil moisture under the different systems are reported.With adequate nitrogen, yields of corn in intercrops varied from around 80% of, to approximately the same as, the yields obtained under conventional systems. Among the legumes, Ladino clover and birdsfoot trefoil survived longest as intercrops. While all intercrops competed strongly with the corn for nitrogen, competition by the grasses was most severe and little difference was shown among the grasses with respect to survival and adaptability. Changes in soil moisture were more rapid under intercrop systems because of deeper and more rapid penetration of rainfall and because of utilization of moisture by the intercrop.
Boron Retention by Clay and Humus Systems Saturated with Various Cations
Authors: Parks W. L. , White J. L. 
Published: July 2010

AbstractThe purpose of this study was to investigate the factors which influence boron retention by clay and humus systems.Fine clay fractions of Wyoming bentonite and kaolinite were saturated with H, Ca, Mg, K, and NH4 ions and the effect of time and wetting and drying cycles studied. Boron retention by various humus systems was determined using an equilibrium membrane cell technique.Under moist conditions base‐saturated kaolinite and bentonite clays retained more boron than hydrogen‐saturated clays, except in the case of NH4 bentonite. Drying the clays resulted in more retention in the hydrogen‐saturated clays than in the basic systems, except for magnesium‐bentonite.In view of the magnitude of boron retention by the humus systems and the chemical reactions between boron and di‐hydroxy organic compounds it is suggested that boron unites with “favorable” diols of the organic matter or those which are gradually released as intermediates of the microbiological breakdown of organic matter in a soil.
A Soil Productivity Score Card
Authors: Berger K. C. , Hole F. D. , Beardsley J. M. 
Published: July 2010

AbstractA soil productivity score card has been designed so that any careful agricultural worker can obtain reasonably reliable ratings for individual fields and farms in Wisconsin. The only tools required are a soil sampling tool, leveling device to approximate slopes in percent, sampling bags, and the Soil Productivity Score Card.The ratings indicate relative current capacities of fields to produce crops, and are adjusted to a possible high score of 100, the sum of 11 optimum figures which include 10 ratings for soil and land characteristics and one for length of frost‐free season. The score card offers a choice of four ratings — low to high — for each characteristic. The user of the card is not asked to recognize and map soil types. Rather, he rates soils by fields. Soil samples are taken from each field for pH, and available phosphorus and potassium quick tests. A total farm score may be derived from the field ratings. The score card has been tested on a variety of soils in Wisconsin and the results have been compared with the U. S. Soil Conservation Service land use capability classification of the same fields, and with soil survey productivity ratings. The comparison shows substantial agreement between the three methods of evaluation. On farms which are without any soil map, the score card helps to provide essential information for the guidance of workers in farm planning and rental programs. Admittedly, there are certain inherent defects in a rating scheme of this kind, such as interdependence of soil factors and differential productivity of a given soil for different crops.