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Articles 301 - 323 of 323
Full-Text Articles in Earth Sciences
How Much Fertilizer Ls Needed For Corn?, Kenneth L. Wells, Keenan Turner
How Much Fertilizer Ls Needed For Corn?, Kenneth L. Wells, Keenan Turner
Soil Science News and Views
Corn producers are faced each year with the decision of how much money to invest in fertilizer for use on their crop. Differing philosophies used by those who make fertilizer recommendations often leave the grower bewildered as to what is best to do. It is not unusual for a producer to be told by his agricultural extension agent that he doesn't need any phosphate and potash on fields which test high in these nutrients while other sources may recommend fertilizer use. The philosophy behind the zero P-K recommendation made by extension agents in such cases is based on University of …
Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale
Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter - Ii, D. C. Wolf, J. T. Gilmour, P. M. Gale
Arkansas Water Resources Center Technical Reports
In Arkansas, approximately 1 Tg of poultry (Gallus gallus domesticus) manure and litter is produced annually. These waste products are commonly applied to pastures as a soil amendment or fertilizer, but excessive application rates and poor management practices could result in nutrient contamination of ground and surface water. The purpose of this study was to: (1) assess the nutrient concentrations in poultry manure and (2) evaluate the nitrogen loss from land-applied poultry litter and manure due to ammonia volatilization and denitrification. Analyses for total Kjeldahl nitrogen (TKN), inorganic nitrogen (Ni), phosphorus (P), and potassium (K) were compared in 12 wet …
Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter, J. T. Gilmour, D. C. Wolf, P. M. Gale
Estimating Potential Ground And Surface Water Pollution From Land Application Of Poultry Litter, J. T. Gilmour, D. C. Wolf, P. M. Gale
Arkansas Water Resources Center Technical Reports
In 1985, more than 750 million broiler chickens were produced in Arkansas. During the same year over 15 million laying chickens produced 3.6 million eggs. The waste products of these agricultural production systems, poultry litter and manure, were about 1 million metric tons. As a result of land application of these wastes, about 5,000 metric tons of annnonium N and 12,000 metric tons of mineralized nitrogen were applied to Arkansas pastures in 1985. Manures contributed about 2-3 percent of the total. The objective of this research was to quantify major components of the nitrogen cycle which influence the ground and …
Use Of Nitrification Inhibitors On Wheat, Lloyd W. Murdock
Use Of Nitrification Inhibitors On Wheat, Lloyd W. Murdock
Soil Science News and Views
Nitrogen is one of the most important inputs 1in wheat production, but sometimes one of the most difficult to manage. Sources of nitrogen commonly used in Kentucky have most or all of their nitrogen in the ammonium (NH+4) form or forms readily converted to NH+4 (anhydrous ammonia 100%, urea 100%, N-solutions 75%, ammonium nitrate 50%), The ammonium form of nitrogen is used by the plant and retained in the soil with little chance 2f loss, In soils with temperatures above 50°F the ammonium is converted to the nitrate (NO3) form of nitrogen. Nitrate …
Concentration Of Nitrate-Nitrogen In Groundwater Central Platte Region, Nebrask 1984, M. E. Exner
Concentration Of Nitrate-Nitrogen In Groundwater Central Platte Region, Nebrask 1984, M. E. Exner
Conservation and Survey Division: Faculty and Staff Publications
No abstract provided.
Using Urea Nitrogen As A Fertilizer, Kenneth L. Wells
Using Urea Nitrogen As A Fertilizer, Kenneth L. Wells
Soil Science News and Views
Solid granular or prilled urea (45-46% N) has become widely available in Kentucky, as has 28% nitrogen solution (UAN solution) which is half urea and half ammonium nitrate. When applied to a field, urea is transformed to ammonium N soon after application. The rate of transformation is greatly increased by urease, the enzyme found to varying degrees in soil and on plants and plant residues. Due to the chemical reactions involved as urea nitrogen undergoes transformation, there is some degree of likelihood for volatilization loss of some N. Whether such a loss will occur, and how much N will be …
Use Of Urea For Crop Production In Kentucky, Wilbur W. Frye
Use Of Urea For Crop Production In Kentucky, Wilbur W. Frye
Soil Science News and Views
Current trends indicate that urea will become the major source of solid and liquid N fertilizer in the future. Although urea has several advantages over other N fertilizers, especially in manufacturing, transporting, and marketing, there are some potential agronomic problems that farmers should keep in mind when using urea.
Effect Of Nitrogen Fertilization On Fall Stockpiled Ky 31 Fescue, Kenneth L. Wells
Effect Of Nitrogen Fertilization On Fall Stockpiled Ky 31 Fescue, Kenneth L. Wells
Soil Science News and Views
Much interest has developed during the past several years on improving utilization of tall fescue by accumulating its growth during the fall and delaying grazing until late fall and winter. This technique takes advantages of the buildup of sugars in the herbage which normally takes place as seasonal temperatures cool to near the freezing point. UK forage research has shown that content of sugars in tall fescue herbage can increase from around 8 percent in late summer to around 20 percent after the first few frosts have occurred in late fall. This sugar buildup greatly increases the feed value of …
Nitrogen Placement For No-Till Corn, Kenneth L. Wells
Nitrogen Placement For No-Till Corn, Kenneth L. Wells
Soil Science News and Views
An estimated 18 to 20 percent of all corn grown in Kentucky is no-till planted. This 400 to 500 thousand acres is directly planted into sod, residues from the previous year, or a winter cover crop. Many field trials have been conducted by University of Kentucky agronomists during the past 15 years to determine nitrogen fertilization practices best suited for this kind of corn production. These recommendations are published annually in "AGR-1 Lime and Fertilizer Recommendations," and call for 25 lbs more actual fertilizer N per acre than conventional corn. This is largely justified by: (1) a greater potential for …
Anhydrous Ammonia Use For Corn, William O. Thom
Anhydrous Ammonia Use For Corn, William O. Thom
Soil Science News and Views
Anhydrous ammonia is the most concentrated form of nitrogen fertilizer available to corn producers in many areas of Kentucky. It is a simple chemical compound made up of one part nitrogen and three parts hydrogen (NH3), existing as a gas at normal outdoor temperatures. This makes it necessary to store and handle the material in closed containers under pressure. The product contains 82% nitrogen, making it one of the highest analysis and most economical fertilizers available for corn production.
Quality Of Legume Inoculants In Kentucky, M. Scott Smith
Quality Of Legume Inoculants In Kentucky, M. Scott Smith
Soil Science News and Views
Successful and profitable production of legumes requires nodulation by Rhizobium bacteria which supply the crop with fixed N. The appropriate strains of bacteria are often absent from soils, since they do not persist without a suitable host plant. Under these conditions, that is when the specific legume crop has not been planted in the field for more than 3 or 4 years, it is necessary to inoculate the seed (or sometimes the soil) with Rhizobium.
Nitrogen Value From Plowing A Sod, M. Scott Smith
Nitrogen Value From Plowing A Sod, M. Scott Smith
Soil Science News and Views
With economic conditions as they are, crop producers need to effectively use all the resources available to them. To help offset high N fertilizer prices, one resource that may be used to significantly reduce production costs is the organic N accumulated in and on soils. When crops are planted into a tilled sod the requirement for added N fertilizer will usually be less than on land previously in row crops. The following discussion considers the processes and factors determining the quantity and availability of N in a sod, and offers some guidelines for estimating the N value of a sod.
Influence Of Soil Type On Nitrogen Fertilization Of Corn, Grant W. Thomas
Influence Of Soil Type On Nitrogen Fertilization Of Corn, Grant W. Thomas
Soil Science News and Views
In Kentucky, response of corn to nitrogen fertilizer is influenced strongly by soil characteristics. These soil properties are of both a permanent and temporary nature.
Use Of Annual Legumes As Winter Cover For No-Till Corn, Robert L. Blevins
Use Of Annual Legumes As Winter Cover For No-Till Corn, Robert L. Blevins
Soil Science News and Views
Legumes in crop rotations hsve traditionally provided nitrogen for nonlegume crops since the early history of agriculture. When in association with the proper strains of Rhyzobium bacteria, legumes are capable of fixing atmospheric nitrogen, which when residues from the legumes decompose, enrich the soil content of nitrogen. Legume cover crops recycle other nutrients, thus reducing leaching losses that often occur in soils during the winter and spring seasons. In addition to these advantages, legume cover crops used with no-tillage corn provide a surface mulch which reduces soil erosion, slows evaporation of soil moisture, increases infiltration of rainfall, and increases soil …
Delayed Nitrogen Applications On Corn, Grant W. Thomas
Delayed Nitrogen Applications On Corn, Grant W. Thomas
Soil Science News and Views
A method of fertilizer application that was standard practice 30 to 50 years ago has become important once again, and for the same reason. When nitrogen fertilizer was expensive and corn was cheap, it was considered prudent to save back some of the nitrogen fertilizer and apply it when the corn was "knee-high." This was thought to be safer because some of the nitrogen added at planting might be lost before the corn was big enough to take advantage of it. The increasing cost of nitrogen fertilizer has made efficient use of this product important again.
Effects Of No-Tillage Fallow As Compared To Conventional Tillage In A Wheat-Fallow System, C. R. Fenster, G. A. Peterson
Effects Of No-Tillage Fallow As Compared To Conventional Tillage In A Wheat-Fallow System, C. R. Fenster, G. A. Peterson
Nebraska Agricultural Experiment Station: Historical Research Bulletins
The benefits of reducing tillage by use of herbicides for weed control emphasizes why research was started to study a fallow system where all tillage was replaced by herbicides. Wheat planting was then the only soil disturbing operation. Objectives of the research were to compare the effects of no-tillage (chemical), stubble-mulch and plow (bare fallow) systems of fallow on: 1. Grain yield. 2. Grain protein. 3. Residue retention. 4. Soil nitrate-nitrogen accumulation. 5. Soil water accumulations during fallow. Data presented are in the form of a progress report. These experiments will continue.
An Examination Of The Inorganic Nitrogen Status Of A Soil Of The Alaskan Coastal Tundra Plain, Norton R. Munn
An Examination Of The Inorganic Nitrogen Status Of A Soil Of The Alaskan Coastal Tundra Plain, Norton R. Munn
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This experiment was designed to measure in situ concentrations of NH4+ and NO3--N in a soil of the arctic coastal tundra plain, to determine if nitrification was taking place in this soil and to determine if the vascular plants growing in this soil could assimilate NH4+-N.
The extractable NH4+-N concentration was approximately 40 μg/g in the 01 horizon and 10 μg/g in the 02 horizon. The NO3--N concentration was approximately 5 μg/g in the 01 horizon and 4 μg/g in the 02 …
The Effect Of Alternate Wetting And Drying On The Ammonium And Nitrite Nitrogen Transformation In Soils, Virupax C. Baligar
The Effect Of Alternate Wetting And Drying On The Ammonium And Nitrite Nitrogen Transformation In Soils, Virupax C. Baligar
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Investigations were carried out to study the effect of alternate wetting and drying cycles on the mineralization, nitrification, and denitrification of soil nitrogen in two soils, in the presence or absence of added ammonium and nitrite. Soils were analyzed at the end of each drying cycle for total inorganic nitrogen, ammonium, and nitrite nitrogen. Gaseous products, i.e., ammonia, and the oxides of nitrogen (NO and NO2) were collected in the course of drying for determination.
The drying cycles accelerated the rate of nitrogen mineralization in both soils and further increased the oxidation of applied and available ammonium. The …
The Influence Of Organic Matter And Ph On Transformations Of Nitrites To Elemental Nitrogen, Mohammad A. Rashid
The Influence Of Organic Matter And Ph On Transformations Of Nitrites To Elemental Nitrogen, Mohammad A. Rashid
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrogen occupies an important and prominent place in plant and animal nutrition. Large quantities are required by plants and must be available in the soil. Recently the use of nitrogenous fertilizers has increased manyfold. In view of the importance of this element in crop production, even greater use is anticipated in the coming years. In order to make full use of the applied nitrogen, continued investigations of soil-nitrogen relationship are imperative; however, this element presents many complex and challenging problems to investigators.
Nitrite Reactions In Soil, John Otto Reuss
Nitrite Reactions In Soil, John Otto Reuss
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Losses of soil nitrogen that cannot be attributed to leaching or crop removal have been observed in many field experiments. Several mechanisms have been proposed to account for these losses.
Moisture And Temperature Effects On The Transformations Of Nitrogen From Applied Ammonium Sulfate In A Calcareous Soil, John Keith Justice
Moisture And Temperature Effects On The Transformations Of Nitrogen From Applied Ammonium Sulfate In A Calcareous Soil, John Keith Justice
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrogen has commonly been a deficient element in the cultivated soils of the world since the beginning of agriculture. The general acceptance of the practice of using manures as a means of increasing plant growth, as shown by the records of ancient civilizations, attest to this fact. Since the time of von Liebig there has been an increasing awareness of the importance of this deficiency in soils. As a result of a better understanding of the problem and the increasing availability of commercial forms of nitrogen, a rapid increase in the use of nitrogen fertilizers has taken place in the …
Development And Evaluation Of Laboratory Methods For Determining The Nitrogen Supplying Power Of The Irrigated Soils Of Northern Utah, Jerald Ross Wight
Development And Evaluation Of Laboratory Methods For Determining The Nitrogen Supplying Power Of The Irrigated Soils Of Northern Utah, Jerald Ross Wight
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrogen is the most widely needed and the most widely used of the fertilizer elements. Yet, in spite of the voluminous research work of evaluating the nitrogen status of soils, laboratory tests for the purpose of predicting need of nitrogen fertilizer are not very widely used. In general, laboratory tests for nitrogen supplying power have not given satisfactory results. Methods currently employed by a few laboratories can be classified either as biological or chemical. In the former method, the soil is incubated under optimum conditions and the amount of nitrate released over a given period of time is measured and …
Bulletin No. 109 - The Nitrogen And Humus Problem In Dry-Land Farming, Robert Stewart
Bulletin No. 109 - The Nitrogen And Humus Problem In Dry-Land Farming, Robert Stewart
UAES Bulletins
The effect of cultivation and the growth of crops upon the nitrogen and humus content of soils has been studied by various investigators, both in America and Europe. In general, the results of the various investigations indicate that cropping and cultivation are very destructive of the organic. matter and the nitrogen of the surface soil.