Nitrification Inhibitors

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

Economics of Legume Cover Crops

We have compared hairy vetch, big flower vetch, rye, and corn residue as winter cover treatments in no-tillage corn production since 1977. One of the objectives of this research is to determine the economic feasibility of using a legume cover crop to supply a portion of the nitrogen needs of a corn crop. Results reported here are based on corn yields obtained during 1977 through 1981 at Lexington and 1980 through 1985 at Princeton

Effects of Soil Erosion on Productivity

About 75 percent of Kentucky\u27s 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 production

New Opportunities for Science Students in Agronomy

High school students interested in science and looking for a field of study that will prepare them for a rewarding career will like the proposed new agronomy programs. The Agronomy Department at the University of Kentucky is preparing to offer undergraduate students three future-oriented options--Plant and Soil Management, Plant Science, and Soil Science. In designing these options, we tried to determine what agronomy students need to be prepared to do in a rapidly changing and highly competitive world of the 1990s

Use of Urea for Crop Production in Kentucky

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

Returning PIK Land to Grain Production

With the end of the 1983 PIK program, much of the acreage that was in the program will be returned to grain production. Farmers who planted cover crops on their PIK fields in 1983 and who plan to return them to grain production in 1984 will be faced with deciding whether to use no-tillage or conventional tillage. The cover crops will provide mulch for no-tillage crops which may be an asset but can contribute to problems as well. Also, weed problems may be worse on PIK land and more difficult to control with no-tillage than with conventional tillage. The decision on what tillage system to use should basis made on the basis of site-specific conditions of each field. Some thoughts to consider are discussed below

Energy Conservation in Corn Production

On-farm production of food and fiber uses about 3% of the annual U.S. energy consumption. About one-third of this energy is directly from fossil fuels used in farm tractors and trucks and for crop drying, while about one-fourth is used in manufacturing and transporting fertilizers. Tillage and N fertilizers are the two largest uses of energy in non-irrigated product ion of crops which are not dried artificially. Thus, the greatest effects of energy conservation can be achieved in these two areas

Nutrient Losses From Conventional and No-Till Cornfields

Farmers must be concerned about both the monetary loss and the threat of groundwater and surface water pollution associated with the loss of plant nutrients from their fields. There is also an increasing public concern about pollution and the role of agriculture in nonpoint-source pollution. Movement of water over the surface of the soil as well as through the soil profile increases the potential for loss of water-soluble nutrients, especially nitrates

Returning CRP Land to Grain Production

Land that was contracted into the Conservation Reserve Program (CRP) was committed to the program for 10 years. The first contracts expire in September 1995, but USDA has already authorized a one-year extension of those contracts. Unless Congress extends the program in the 1995 Farm Bill the contracts will begin expiring on September 30, 1996, as the 10- year period elapses, and continuing until all of the acres that were set aside in the program are released. In Kentucky, about 440,000 acres were contracted in the program from 1986 to 1992. Most of the land is highly erodible, and farmers were required to establish and maintain a vegetative cover to protect the soil from erosion. Grasses or grass-legume mixtures were established on about 434,000 acres of this land. The rest was planted to trees or wildlife habitat. A 1993 survey by the Soil and Water Conservation Society indicated that, without extension of the CRP and assuming current commodity prices, 63% of U. S. farmers would return their land to row crop production the first year after their contracts expire. About 23% would continue in grassland for hay or grazing. In the USDA Appalachian region where Kentucky is listed, those estimates are 48% returned to row crops, 23% left in grass, and 13% left in trees. Much of Kentucky, especially western Kentucky, will probably respond more like the Corn Belt region where 73% of CRP acres are expected to be cropped and only 16% will be kept in grass. The crops will be mostly com and soybeans

Urease Inhibitor Reduces Ammonia Loss from Surface-Applied Urea

Urea is the world\u27s leading N fertilizer, and its use continues to grow. In the USA, for example, the use of urea increased 50 fold from 1955 to 1986. During that same time, its use in Kentucky increased from 214 to more than 112,000 tons per year, which was 28% of the N used in Kentucky in 1986. The increasing popularity of urea is due to advantages over other N fertilizers in its manufacture and to its use in making most N solutions, another rapidly growing form of N fertilizer. Desirable qualities of urea include the highest N content of all solid N fertilizers (45-46%), excellent handling properties, and dissolves readily in water. There is, however, a serious agromonic management problem with urea