Agronomy and Crop Sciences Commons^™

1990 Kentucky Winter Annual Legume Variety Test, L. M. Lauriault, Norman L. Taylor, Jimmy C. Henning, W. T. Edmonson

Agronomy Notes

Cover crops are often used in Kentucky following the harvest of row crops such as tobacco, corn, and soybeans. Living cover crops can prevent erosion, reduce leaching of nutrients, and supply grazing, green manure, or a plant cover in which to no-till the following spring.

Triazine Resistant Pigweeds In Kentucky Corn Fields, Jonathan D. Green, Michael Barett, Mike Radford

Agronomy Notes

Smooth pigweed (Amaranthus hybridus) control from atrazine and/or simazine (Princep) has been unsatisfactory in some Kentucky corn fields. Many of these fields have grown corn where one or both of these herbicides have been used continuously for several years. These two triazine herbicides, particularly atrazine, are used annually on over 90% of the corn grown in Kentucky. Other areas in the U.S. and around the world have reported. unsatisfactory control from atrazine where triazine resistant pigweed has developed.

Some Effects Of Shifting To Conservation Tillage Systems For Intensive Production Of Corn And Soybean, Kenneth L. Wells, H. C. Vaught, David Heisterburg

Agronomy Notes

About three-fourths of Kentucky's cropland base occurs on sloping land with some degree of erosion hazard. During the past decade, production of soybeans and corn increased rapidly in Kentucky, particularly on sloping land. This resulted in severe erosion on many farms, particularly in the "intensive grain producing counties. Much of this field erosion could be greatly reduced by developing a system for each field that would incorporate use of such agronomic practices as sod waterways, no-till planting, contour plowing, minimum tillage, strip cropping, double-cropping, winter cover crops, crop residue management and rotations. It is believed that the current acreage of …

Using Performance Test Results In Soybean Variety Selection In Kentucky, Todd W. Pfeiffer

Agronomy Notes

Many soybean varieties are available to, soybean producers in Kentucky each year. Information is available from company advertisements, private yield tests, and public performance tests which producers can use when selecting a variety. The question arises as to how this information relates to variety performance on a particular farm. The value of yield test data lies in the predictive ability of that data. How well does data from a set of environments predict relative performance among varieties over the wide range of possible environments in which those varieties can be grown? The first objective of this note is to discuss …

Forage Production On Reclaimed Surface Mined Land In Eastern Kentucky, William O. Thom, H. B. Rice

Agronomy Notes

Forage crop production for hay or pasture can be important for the utilization of the many acres of reclaimed surface mined land in eastern Kentucky. Even though grasses and legumes are seeded during reclamation to provide ground cover and reduce soil loss, these areas are not usually managed for forage crop production. On the other hand, these vast land areas have the capability to provide significant amounts of desirable grasses or grass-legume mixtures for cattle when well-managed.

The Effect Of Three Tillage Systems On Bulk Density And Porosity Of A Pembroke And A Beasley Soil After Three Years, Kenneth L. Wells, John H. Grove

Agronomy Notes

Many grain producers in Kentucky use a 3 crop in 2 year rotation of corn followed by small grain-soybeans, and commonly no-till the soybeans and corn in order to intensively use sloping land for continuous grain production. Because of the intensity of machinery traffic in this system, growers are concerned that continuous no-till management may cause compaction, and that such fields may need occasional primary tillage. In order to obtain' information regarding things situation, we conducted a test for 3 years on the farm of' Philip Lyvers, in Marion County, Kentucky, in a field which was being used in a …

Row Widths For Full Season Soybeans In Kentucky, Todd W. Pfeiffer, Morris J. Bitzer, James H. Herbek, Jereme Orf, D. Pilcher, Charles Tutt, L. Zen

Agronomy Notes

Soybean yields in Kentucky have increased steadily in the past 20 years as a result of improved varieties and production practices. To achieve even higher yields new varieties and better production practices need to be developed and tested. One possibility for increasing soybean yields is to plant in narrow rows using varieties which respond to this practice. Although previous research in Kentucky has not shown a yield advantage for full season soybeans planted in narrow rows, researchers in other states have recently shown increases in yield with narrowing row widths. A number of new varieties have also been developed specifically …

Effect Of Lime On No-Tillage Corn Yields, Robert L. Blevins, Lloyd W. Murdock

Agronomy Notes

The rapidly growing popularity and adoption of no-tillage systems of corn production have required us to re-evaluate some of our long established soil fertility practices and recommendations. Recent work by researchers at Kentucky and adjacent states show that the soil surface becomes very acid after a few years of continuous no-tillage corn production. This rapid decrease in soil pH is primarily associated with surface application of nitrogen fertilizers. Most lime recommendations and related research information for row crop production are based on plow-down application. Therefore, the effectiveness of surface-applied and unincorporated lime under no-tillage systems becomes a question of concern. …

Relationship Of Weed Control And Soil Ph To No-Tillage Corn Yields, J. J. Kells, C. E. Rieck, Robert L. Blevins, Charles H. Slack

Agronomy Notes

Atrazine and simazine are used for selective control of a broad spectrum of weeds in corn. Over 80% of the U.S. corn production is treated with one or the other of these two s-triazine herbicides. In Kentucky they are used annually on over 800,000 acres of corn, including over 200,000 acres of no-tillage corn. When added to the soil these compounds are ultimately degraded to non-phytotoxic compounds. The rate of degradation is dependent upon the physical, chemical, and biological properties of the soil. Although atrazine and simazine are chemically similar, simazine is considered to degrade slightly slower than atrazine after …

Influence Of Time Of Application Of Nitrogen Fertilizer On Corn Yields, Harold F. Miller, Kenneth Wells, Morris J. Bitzer, G. W. Thomas, R. E. Phillips

Agronomy Notes

Soil moisture conditions can have a large effect on crop responses to nitrogen fertilization. Kentucky's usual climatic pattern of periods of heavy rainfall and relatively warm temperatures during the winter and spring seasons influences expected yield responses of corn to applied nitrogen. If nitrogen fertilizer is applied in late winter or early spring, some of it may be lost before the plants have made sufficient growth to take up appreciable quantities. The amount of loss that might be expected will be influenced by the amount of rainfall, temperature, amount of organic matter and drainage of the soil.

Grass Seed Production, Robert C. Buckner, Warren C. Thompson

Agronomy Notes

Producing cool season grass seed crops has historically been a profitable venture on Kentucky farms.

When growing maximum yields of grass seed, the pH level should be maintained between 6.0 and 7.0, when the recommended rates of limestone are used, and when phosphate and potash are maintained at medium-to-high levels (based on a soil test). Similarly, grass should be grown in pure stands. Weeds and insects must be controlled to prevent yield reduction.

Following seed harvest, excess herbage should be removed, preferably by grazing. All cool season grasses can be grazed until growth stops in the late fall or early …

Tobacco Stalk Production, Value And Use, George D. Corder, Harold F. Miller

Agronomy Notes

When Kentucky farmers finish stripping the 1963 tobacco crop they will have 176,000 tons of tobacco stalks worth $2 million on their farms.

These stalks will contain 9.8 million pounds of nitrogen, 932,000 pounds of phosphorus (2 million pounds of P₂O₅) and 13 million pounds of potassium (15.6 million pounds of K₂O). Equal amounts of these plant nutrients bought in commercial fertilizers in 1963 would have cost more than $2 million.