Soil Science Commons^™

Quality Alfalfa Seed Production In The West, Vern L. Marble

Kentucky Alfalfa and Stored Forage Conference

Alfalfa seed production in the western United States has become a specialized business, and can no longer be considered as a "catch crop" to be harvested along with a hay production program in historical production areas in the Plains and Rocky Mountain states which produced approximately 80 percent of all of the seed produced in the late 1940's and early 1950's. In 1981 the seven western states of California (47.8 percent), Idaho (12.2 percent), Nevada (8.7 percent), Washington (7.7 percent), Oregon (4.2 percent), Montana (4.5 percent), and Utah (3.2 percent) produced 87.5 percent of the total 1981 production of 117 …

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.

Band Vs. Broadcast Application Of Fertilizer, Kenneth L. Wells

Soil Science News and Views

Current fertilizer prices coupled with other increased production costs have renewed interest in band applications of fertilizer as a means of lowering fertilizer costs while maintaining crop yields. Fortunately, much basic soil fertilizer research has been conducted over the years which provides an understanding of the relative merits of band and broadcast placement. The following discussion outlines the basic considerations involved in deciding which of these two placement methods may be more economically useful for specific crop production systems. To better understand these considerations, certain principles related to adding fertilizer to the soil should be kept in mind. These are …

Liming Needs Of Kentucky Soils, William O. Thom

Soil Science News and Views

A sound liming program is the first step in building and maintaining soil fertility. Lime lowers the acidity (raises pH) of soil and prevents the adverse effects of high concentrations of soluble aluminum, iron, and manganese on crop growth--effects often associated with acid soils. Maintaining a suitable pH assures adequate levels of calcium and magnesium. Liming an acid soil increases the availability of most essential plant nutrients, increases the efficiency of fertilizers, improves the effectiveness of some herbicides, and makes beneficial soil organisms more active.

Effect Of Herbicides On Performance Of Aerobic Dairy Lagoons, John D. Bottom, Joseph L. Taraba

Biosystems and Agricultural Engineering Faculty Publications

The herbicides glyphosate, bromacil, and dalapon were assessed for their affect on the oxygen uptake of microorganisms from an aerated dairy lagoon at 20 °C. The maximum recommended addition of herbicide active ingerdient to a lagoon is: glyphosate (isopropyl amino salt)—0.42 mg/L; bromacil—3.70 mg/L; and dalapon (85.8 percent Na salt and 14.2 percent Mg salt)—1.95 mg/L. In addition, microorganism isolates from the aerobic dairy lagoon were incubated under aerobic and anerobic conditions at room temperature to assess the effects of the herbicides. Under aerobic incubation, it was found that neither herbicide type nor herbicide concentration affected isolate growth. Under anaerobic …

Molybdenum Nutrition Of Crops In Kentucky, J. L. Sims

Soil Science News and Views

Molybdenum (Mo) is one of eight micronutrient elements required for the growth of plants. Research conducted in California nearly 40 years ago established its need for plant growth. Mo deficiencies have been reported throughout the world, especially on acid soils in the United States, Australia, and New Zealand. Generally, the Mo requirement of leguminous crops is greater than for non~legumes, but many non-leguminous field and vegetable crops have responded to additions of fertilizer Mo under severe deficiency conditions. Of all the nutrient elements required by plants for growth, Mo is needed in smallest amounts.

Use Of Magnesium (Mg) For Crop Production In Kentucky, John H. Grove

Soil Science News and Views

Magnesium (Mg) is an important element in the nutrition of plants and animals, although it has long been considered a "secondary" nutrient for plants. Nitrogen (N), phosphorus (P), and potassium (K) are "primary'' nutrients and are usually given the greatest consideration in crop fertility programs. However, as yield levels have risen, more attention has been directed towards Mg and other nutrient elements. Concern about hypomagnesemia (grass tetany) in ruminants (cattle, sheep) has led to particular concern about soil and plant Mg levels.

Nitrification Inhibitors, Wilbur Frye

Soil Science News and Views

Nitrogen often limits the production of nonlegume crops because of inefficiency of N fertilizers. In some cases, more than half the fertilizer N may be lost from the soil. Therefore, it is important to use it as efficiently as possible. One way in which N fertilizer efficiency may be improved is by slowing the nitrification process in the soil.

Cover Crops And Crop Residues, Robert L. Blevins

Soil Science News and Views

In Kentucky, erosion hazard is by far the major limitation for use of cropland. It has been estimated that about 11.4 million acres are subject to erosion hazards. This means that approximately 75% of the soils potentially suited for cropland is sloping enough that risk of erosion is the greatest limitation in its use for crop production. Probably the greatest risk of erosion results from leaving row-cropped fields unprotected over winter. The use of cover crops and proper management of crop residues to stablize these soils during the winter months are relatively inexpensive agronomic practices that are very effective in …

Soil Surveys In Kentucky, Harry Hudson Bailey

Soil Science News and Views

Fifty-four Kentucky counties have modern soil surveys (published 1959, or later) using the mapping and soil classification procedures of the National Cooperative Soil Survey. The cooperators in the program include the USDA-SCS, USDA-FS, Kentucky Department for Natural Resources and Environmental Protection and the Kentucky Agricultural Experiment Station.

The Status Of Sulfur Fertilization Of Crops In Kentucky, Lloyd W. Murdock

Soil Science News and Views

Sulfur has long been recognized as being essential for the growth of plants and animals due to it being necessary for production of several amino acids. Although regarded as a "secondary" element, it is required by plants in fairly high amounts, very similar to that of phosphorus. Sulfur deficiency symptoms in plants are somewhat similar to those of nitrogen since an overall uniform pale-green leaf color develops. Sulfur deficiencies are often found in crops growing on sandy soils with low organic matter content.

Use Of Plant Analysis, William O. Thom

Soil Science News and Views

Plant analysis is the laboratory determination of several nutrient elements on a single sample of plant material. In recent years this technique has been more frequently used to diagnose soil fertility problems 0r to monitor soil fertility recommendations on growing crops. Current instrumentation makes it possible to rapidly determine several elements on an extract from a plant sample.

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.

Modeling Soil Water Contents And Their Effects On Stream Flow In Kentucky, Grant W. Thomas, Ronald E. Phillips, David E. Radcliffe, Scott Shepard

KWRRI Research Reports

Soil water contents of eight important soil series in Kentucky were measured periodically during the summer growing season for four years, 1977 through 1980. The soils divided into three groups according to their behavior. The first group (Maury and Crider) is well-drained and never showed excess water above field capacity at any time during the four seasons. The second group (Zanesville, Lowell, Calloway, Grenada and Shelbyville) showed perched water tables at times, especially during the early part of the growing season. The third group was represented by the Huntington soil which has a permanent water table.

The in-situ field capacity …

Fertilizing Soybeans, Monroe Rasnake

Soil Science News and Views

Soybeans need a fertile soil with a pH of about 6.4 for maximum production. This condition is best attained through a regular soil testing and fertilization program. A fertility program based on fertilizer and lime. use as determined by soil testing is more economical and more effective than applying large amounts of fertilizer at planting. Soil testing is the key.

Fluid Fertilizers, Kenneth L. Wells

Soil Science News and Views

Fluid fertilizers are available in a wide range of products to Kentucky farmers. Although the term "liquid fertilizer" is commonly used to describe all fluid fertilizers, in reality the two terms do not imply the exact same meaning. Technically, all fertilizers of fluid consistency which can be transferred by pump are called "fluid f ertilizers11. This is the proper term to use in the broadest sense to describe such materials. There are two general types of fluid fertilizers. One group is called "suspensions" or "slurries", and the other group is referred to as "clear liquids".

Water Relationships Of Kentucky Soils, Ronald E. Phillips, Grant W. Thomas

Soil Science News and Views

Plant water stress is the most limiting single factor in crop production in Kentucky. It almost always occurs sometime during July and/or August even though it's variability makes it hard to predict. Even though the 1979 growing season was an exception to this generalization the 1980 growing season was a vivid reminder of this fact especially in Western Kentucky.

Field Preparation For Pasture Renovation, Harold B. Rice

Soil Science News and Views

Grassland renovation is the improvement of pasture and hay fields by partial destruction of the sod, plus liming, fertilizing, and seeding as may be required to establish or re-establish desirable forage plants without an intervening crop. In Kentucky, this improvement has been primarily through the seeding of legumes such as clovers and alfalfa into grass sods.

Since liming and fertilizing are essential steps in pasture renovation the FIRST step is to have your soil tested to determine how much lime and plant nutrients to apply. Seedbed preparation will range from none to complete disturbance of the existing sod depending on …

Fertilizer Recommendations, William O. Thom

Soil Science News and Views

Fertilizer recommendations are interpreted from a soil test value. The interpretations are based on field research that compares crop yield to soil test levels and the amount of fertilizer applied. These field studies provide data to compare relative yield of a crop for a measured soil test value and fertilizer recommendations are then calibrated to these soil test values.

Soil Drainage---Effects On Crop Production, Kenneth L. Wells

Soil Science News and Views

One of the major physical properties of soil which is important to crop production is drainage through the rooting zone. This characteristic greatly influences aeration in the rooting zone, and the degree of aeration greatly influences several important biochemical reactions of economic importance to crop production.

Conservation Tillage Practices, Monroe Rasnake

Soil Science News and Views

The loss of topsoil from farmlands has become a serious problem in some parts of Kentucky. During the past 20 years, grain crop acreage has tripled. The production of soybeans, which leaves the soil in a condition more susceptible to erosion, has grown from almost none to 1.7 million acres. Much of this increased acreage has come at the expense of soil conserving crops such as hay and pasture on sloping class II and III land with an erosion hazard. Use of large equipment, larger fields, chemical weed control, etc., has added to the scope of the problem with which …

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 …

Effects Of Soil Erosion On Productivity, Wilbur Frye

Soil Science News and Views

About 75 percent of Kentucky's agricultural land is sloping enough that potential erosion losses must be considered in its management. In addition to the effect of soil erosion on water pollution is the question of its effect on the productivity of the soil. This is a complex question due to the interactions of the many factors that affect crop growth. Furthermore, the same degree of erosion has a greater adverse effect on some soils than on others. The kind of erosion that has taken place or is taking place is a major factor in making land use decisions for crop …

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.

Soybean Inoculation, J. L. Sims

Soil Science News and Views

Well-nodulated soybean plants are needed for most efficient soybean production. Recent research by University of Kentucky Agronomy Department personnel indicated that on Maury soil without N fertilizer, nodulating plant types of Clark 63 variety yielded 8 bushels per acre more than the non-nodulating Clark 63. With application of 125 lbs N per acre to the non-nodulating type only, both types yielded the same, showing the value of good nodulation.

Determination Of Sediment Filtration Efficiency Of Grass Media, David T. Kao

KWRRI Research Reports

Vegetative filters serve the purpose of retarding flow. As a result the sediment carrying power of flowing water in a vegetated channel is greatly reduced and silting takes place along the section where the vegetation is planted.

The mechanism of the filtering action of real or artificial vegetation can be described by a simplified principle, in that a gross reduction of turbulent fluctuation of the fluid is involved. This in turn allows the sediment particles to settle under the force of gravity more readily. In the case of nonsubrnerged flow, solid particles may settle out even faster due to the …

Ground Driven Powered Tillage, Larry G. Wells, E. M. Smith, D. E. Hammett, H. J. Thompson Jr.

Biosystems and Agricultural Engineering Faculty Publications

A ground driven powered tillage device is described which utilizes a passive rolling coulter propelled through the soil by a prime mover. The reaction torque imparted by the soil to the coulter is delivered via a torque transfer unit to a powered tillage blade. The tillage blade rotates counter to the direction of the passive rolling coulter and prepares a tilled furrow of some predetermined depth for seed placement and coverage.

Analysis is presented in which the torque developed by a passive rolling coulter engaging the soil is predicted. A relationship is presented for determining the velocity ratio between the …

Influence Of Nitrogen Fertilization On The Quality And Quantity Of Streamflow From A Forested Watershed, George B. Coltharp, Michael T. Shearer, Everett P. Springer, Robert F. Wittwer

KWRRI Research Reports

This project was designed to determine the effects of nitrogen fertilization on the quality and quantity of streamflow eminating from an eastern hardwood forest watershed. A 40.67 ha watershed, located in mountainous eastern Kentucky, was aerially fertilized in late April 1975. The forest stand was principally oak, hickory, and yellow poplar, 50 - 55 years of age and in a relatively undisturbed condition. A helicopter applied anunonium nitrate at a rate of 504 kg/ha. Because a large part of applied nitrogen fertilizer ends up in the highly mobile nitrate nitrogen.form, this is the principal ion monitored in this study. No …

Effects Of Soil Injection Of Liquid Dairy Manure On The Quality Of Surface Runoff, I. J. Ross, S. Sizemore, J. P. Bowden, C. T. Haan

KWRRI Research Reports

Liquid dairy manure has been injected on the soil contour to depths of 6 and 12 inches and applied to the surface of a Bluegrass sod and a bare tilled soil. Application rates of 9,250 gallons per acre were used. Runoff from 9-foot-square plots which were sprinkled at rates of 2.5 inches per hour on sod and 1.5 inches per hour on bare soil was collected and analyzed for various pollution parameters including COD, N, TS, TSS, pH, DO, and Fecal Coliform. The effects of pollutant yield in the runoff have been determined for various treatments.

Injection of the manure …

The Response Of Various Soil Strength Indices To Changing Water Content And Bulk Density, Larry G. Wells, O. Treesuwan

Biosystems and Agricultural Engineering Faculty Publications

Various soil strength parameters were measured in the laboratory using a bevameter and a recording soil cone penetrometer. Measurements were made at various levels of soil bulk density and water content. Results were discussed in terms of similar published analyses. Two dissimilar methods of predicting vehicular tractive performance were compared and evaluated in terms of potential utility with respect to prediction of soil trafficability.