Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 24 of 24
Full-Text Articles in Physical Sciences and Mathematics
The Corn Belt Multi-State Corn Nitrogen Rate Calculator: Not Reliable For Kentucky Corn Producers, John H. Grove, Gregory J. Schwab
The Corn Belt Multi-State Corn Nitrogen Rate Calculator: Not Reliable For Kentucky Corn Producers, John H. Grove, Gregory J. Schwab
Soil Science News and Views
Because of the rising price of nitrogen (N) fertilizer, university personnel across the country are in the process of fine tuning N recommendations for com. Historically, each state has had different N recommendations based on research results obtained in different production systems and growing environments across each state. Some states in the Com Belt have used a yield potential (yield goal) approach to N recommendations. The expected yield is multiplied by a factor (usually 1.2) and then N credits for previous crop, manure, etc. are subtracted. One problem with this method is that as com yields increase N recommendations also …
Value Of Nutrients In Poultry Litter When Applied In The Fall, Monroe Rasnake, George Kelley
Value Of Nutrients In Poultry Litter When Applied In The Fall, Monroe Rasnake, George Kelley
Soil Science News and Views
The value of nutrients in poultry litter depends not only on how much nitrogen (N), phosphorus (P) and potassium (K) it contains, but also on how it is handled and applied. The following table compares the value of 19 poultry litter samples from Hopkins County analyzed for N, P & K and the litter then spread in the fall. The samples include pullet, breeder and broiler manures, with storage times up to one year. Nutrient values were based on a comparison with urea (46-0-0) at $199/ton, triple super phosphate (0-46-0) at $215/ton and muriate of potash (0-0-60) at $165/ton.
How Accurate Are Uk's Nitrogen Recommendations For Corn?, Kenneth L. Wells, James E. Dollarhide, David C. Ditsch
How Accurate Are Uk's Nitrogen Recommendations For Corn?, Kenneth L. Wells, James E. Dollarhide, David C. Ditsch
Soil Science News and Views
Average corn yields produced on soils with high yield potential have steadily been increasing in Kentucky during the past several years. Yields from such soils in years with adequate amounts of rainfall well distributed over the growing season (May-September) may average 180 to 200 bushels per acre. A bushel of corn with crude protein content of 8 to 9% contains about 1.3 to 1.4% total nitrogen (N) on a dry matter basis. This is about 0.6 to 0.7 lbs total N per bushel of corn (at 15.5% moisture), or 108 to 126 lbs N per acre for a 180 bu/A …
Should Burley Tobacco Farmers Be Concerned About High Rates Of Nitrogen Fertilizers?, Robert C. Pearce, Gary K. Palmer
Should Burley Tobacco Farmers Be Concerned About High Rates Of Nitrogen Fertilizers?, Robert C. Pearce, Gary K. Palmer
Soil Science News and Views
The use of nitrogen (N) fertilizer for tobacco production is necessary because (1) tobacco takes up sizable amounts of N, and (2) most soils cannot provide adequate amounts of N. Rates of fertilizer N recommended by the University of Kentucky for burley tobacco production vary based on past cropping history, and under certain conditions can be as high as 350 lbs. N/A However, since tobacco is a high value crop, and profit margins are high, farmers often apply more N than is recommended as insurance against crop losses. The perception of widespread over-application of fertilizer N has resulted in increased …
Production And Nutrient Content Of Broiler Litter, Monroe Rasnake, Mike Williams
Production And Nutrient Content Of Broiler Litter, Monroe Rasnake, Mike Williams
Soil Science News and Views
How much litter is produced in a broiler house in one year? How much nitrogen, phosphorus, and potassium is present in broiler litter? These are questions that concern broiler producers and others who have an interest in the use and safe disposal of broiler litter. A project was initiated with support of the Tennessee Valley Authority and the cooperation of several broiler producers in Carlisle County to help answer these questions.
An Estimate Of The Source And Uptake Of Nitrogen In Continuous No-Till Com Grain Production, Kenneth L. Wells
An Estimate Of The Source And Uptake Of Nitrogen In Continuous No-Till Com Grain Production, Kenneth L. Wells
Soil Science News and Views
The U.S. Environmental Protection Agency (EPA) has established a maximum nitrate nitrogen (NO3-N) content of 10 parts per million (ppm) for safe drinking water. Because of this, the effect of commercial nitrogen (N) fertilizers in agricultural production as a contributor of NO3-N to surface and groundwater is now being widely examined. Since corn production in the US is the largest single source of fertilizer N use, averaging perhaps 100-150 lbs N/A on the 70-80 million acres of corn produced annually, an understanding of N utilization and losses in corn production is helpful in determining the role …
Estimated Nutrient Content And Uptake By Kentucky's Crops, Kenneth L. Wells, William O. Thom
Estimated Nutrient Content And Uptake By Kentucky's Crops, Kenneth L. Wells, William O. Thom
Soil Science News and Views
A commonly asked question by crop producers is, "how many pounds of plant nutrients do my crops take up?" While the absolute answer to this varies by yield and soil fertility, useful estimates can be made from research data to enable a producer to have a "ballpark" value for nutrient up-take by some of the major crops of Kentucky. The following tables contain estimates of nitrogen (N), phosphorus (P),and potassium (K) contained in certain crops and the amount of N, phosphate (P2O5), and potash (K,O) taken up by tobacco, corn, soybeans, wheat, alfalfa hay, clover grass …
Broiler Litter For Topdressing Tall Fescue, Monroe Rasnake, David Watson
Broiler Litter For Topdressing Tall Fescue, Monroe Rasnake, David Watson
Soil Science News and Views
A test was started in Princeton in 1991 to observe the response of tall fescue to applications of nitrogen fertilizer and broiler litter. Five treatments were used: two and four tons of litter per acre, 100 lbs nitrogen (half in May and half in July), 100 lbs nitrogen plus soil test recommended rates of phosphate and potash (only 55 lbs of Phosphate applied in 1991) and a check which had no nutrients applied. The treatments began in May 1991 on an established stand of tall fescue on a fragipan soil at the U.K. Research and Education Center in Princeton.
Poultry Litter As A Nitrogen Source For Corn, Monroe Rasnake, Larry Reber
Poultry Litter As A Nitrogen Source For Corn, Monroe Rasnake, Larry Reber
Soil Science News and Views
Development of an intensive poultry production industry in western and south-central Kentucky will make poultry litter available to many farmers. It is estimated that 45, 000 tons per year will be produced just in the Jackson Purchase Area. One of the most efficient uses of this litter is as a nitrogen fertilizer source for corn.
Farm Nutrient Management, William O. Thom
Farm Nutrient Management, William O. Thom
Soil Science News and Views
Nutrient management is becoming a buzz word in today's vocabulary of crop and livestock production. In the past it was applied to efficient management of all nutrient sources used for crop production. More recently it is being used to account for all nutrients used for crop production that are brought onto the farm, removed from the farm in crop and animal products, and reallocated within the farm unit. Nitrogen, phosphorus, and potassium are the nutrients of concern with nitrogen and phosphorus being most important.
Managing Soil Content Of Nitrate Nitrogen, Kenneth L. Wells
Managing Soil Content Of Nitrate Nitrogen, Kenneth L. Wells
Soil Science News and Views
The concerns about leaching of fertilizer nitrogen (N} into groundwater which were raised in the late 1960's were largely silenced during the 1970's as our agricultural economy was massively expanded. But since the early 80's they have been raised again to the point that national legislation (the Clean Water Act) was put into place to bring purity of the nation's water supplies into compliance with EPA-established standards. Beyond the apprehension largely about nitrate (NO3) levels in groundwater, the groundwater issue today also includes concerns about pesticides. At the current time, the public is apprehensive about drinking water and …
Has The Nitrate-Nitrogen In Streams Draining Agricultural Watersheds In Kentucky Changed In The Last 18 Years?, Grant W. Thomas, Gerald R. Haszler, James D. Crutchfield
Has The Nitrate-Nitrogen In Streams Draining Agricultural Watersheds In Kentucky Changed In The Last 18 Years?, Grant W. Thomas, Gerald R. Haszler, James D. Crutchfield
Soil Science News and Views
In 1971 and 1972, we sampled streams across Kentucky for nitrate-nitrogen (NO3-N) during the high-water flow months of January through June. The results were variable and showed a dominant effect of geology and lesser effects of both time and land use on the results. Since that time, use of fertilizer nitrogen (N) has nearly doubled in Kentucky and, further, there is a high degree of concern among the public that NO3-N from fertilizer use may be contaminating streams. The US Environmental Protection Agency has set a maximum of 10 ppm NO3-N in water as …
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 …
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 …
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.