Plant Sciences Commons^™

Common Pokeweed Management In Corn And Soybeans With A Conservation Tillage Cultivator And Herbicides, Jonathan D. Green, William W. Witt

Agronomy Notes

Common pokeweed (Phytolacca americana L.) is a warm-season perennial that grows well in nondisturbed areas such as fence rows and woodland borders. In recent years it has begun spreading to com and soybean fields where no-tillage practices are used. The deep taproot that is characteristic of common pokeweed, makes this weed difficult to manage, particularly in no-till plantings. The green leaves, fleshy stems, and purple berries of common pokeweed can inhibit the harvesting process and lead to discounts at the elevator for high moisture and stained seed.

The equipment industry has developed cultivators with large sweeps capable of operating …

On-Farm Testing Of Early Maturing Soybeans, Larry J. Grabau, Colleen C. Steele, N. Gift

Agronomy Notes

Maturity Group (MG) II soybean varieties have performed well in University of Kentucky tests over the past several years. Six tests from 1986 to 1989 showed MG II varieities to outyield MG I, III, or IV varieties. During those relatively dry years, MG II may have been able to better utilize limited soil moisture than did later maturing varieties. Across the years 1990 to 1993, four planting date tests showed continued strong performance by MG II' varieties, although MG III and IV varieties had slightly higher yield averages during those wetter years. In summary, over the last eight years of …

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.

Response Of Soybeans To Available Potassium In Three Kentucky Soils, John H. Grove, William O. Thom, Lloyd W. Murdock, James H. Herbek

Agronomy Notes

Soybeans are produced in nearly all of Kentucky's soil physiographic regions. Soybean response to potassium (K) fertilization and soil test Kvaries with soil type and location. This variation may be associated with the wide range in soil chemical and mineralogical properties among the different regions. Of particular interest are differences in that level of soil test Kat which no further yield response to K fertilizer application would be expected. The main objective of this work was to evaluate the soil K-soybean response relationship on three different field sites where soybean yields were increased by fertilizer K. Several measures of soil …

Potential Use Of Ethephon To Control Lodging Of Soybeans, Larry J. Grabau, Robert C. Pearce, J. V. Konsler

Agronomy Notes

Lodging is sometimes a serious problem with soybeans in Kentucky, especially with the full season crop. However, under, excellent growing conditions, or if planting rates are too high, substantial lodging of double crop soybeans can also occur. If lodging occurs early during seed fill, it can reduce yields directly by causing poorer light use and increasing diseases. If lodging occurs late during seed fill, it will have little direct effect on yield, but may have an indirect effect by slowing down harvest and increasing harvest losses. Thus, the use of an inexpensive chemical to reduce soybean lodging is attractive. Our …

Stubble Losses Of Kentucky Soybeans, Larry J. Grabau, Todd W. Pfeiffer

Agronomy Notes

Double crop soybeans in Kentucky tend to be shorter than plants from full season plantings. Since lowest pod height is related to plant height, double crop soybeans may be subject to greater harvest losses due to pods remaining below the level at which the combine header is operated. While it would be possible to lower the header closer to the soil to pick up some of those pods, that would slow down harvest and increase the risk of picking up stones and other trash. Although the actual cutting heights used in Kentucky are not known, some producers use combines with …

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 …

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 …

Evaluation Of A Skip-Row Planting System Or Plant Run-Over As Management Practices On Full Season Soybeans In Narrow Rows, Todd W. Pfeiffer, Morris J. Bitzer, Jereme Orf, D. Pilcher

Agronomy Notes

In recent years there has been an increased interest in narrow row and solid seeded soybeans in Kentucky. Soybeans seeded in narrow rows have an earlier canopy closure which allows a longer time for the soybean plants to intercept the maximum amount of sunlight. The shading effect which results from earlier canopy closure also aids in weed suppression. More farmers are now seeding full season soybeans in narrow rows or solid seeded stands; because cultivation is eliminated, however, some are hesitant to adopt narrow row production practices for fear of inadequate chemical weed control. With the recent increase in effective …

Foliar Fertilization Of Soybeans - 1977, Lloyd W. Murdock, Preeda Boon-Long, Dennis B. Egli, Kenneth L. Wells

Agronomy Notes

Field investigations on the effect of foliar fertilization were continued on soybeans during 1977. Results from our 1976 studies have previously been published.

In 1976 we tested a material produced by TVA. We used the same TVA-material in 1977 and in addition, included a commercially available product (Folian^tm, manufactured by Allied Chemical Corporation).

Manganese Fertilization Of Soybeans, Lloyd W. Murdock, Harold F. Miller, Doyle Peaslee, Wilbur Frye

Agronomy Notes

Only a small quantity of manganese is essential for plant growth however under certain soil conditions even this is not available to the plant. Depending on severity, manganese deficiency will retard plant growth and may drastically decrease yields. A deficiency of manganese will affect the photosynthesis system of the plant. The visual symptoms of a manganese deficiency on soybeans is interveinal chlorosis of the leaves. The veins remains green until the chlorosis nears the white stage then they also lose their color.

Foliar Fertilization Of Soybeans, Kenneth L. Wells, Dennis B. Egli, C. E. Wyatt, John Kavanaugh

Agronomy Notes

Research reported by Iowa State University during the winter of 1975-76 suggested that a means of increasing soybean yields by use of a specific foliar fertilizer had been demonstrated (1976). Theory proposed to explain the reported responses was as follows: Up to the seed filling period in soybean growth, soybean roots and activity of nitrogen-fixing bacteria contained in root nodules are capable of supplying the necessary nutrients to meet the plants demands. However, as seed filling begins root growth stops and nodule activity declines. This results in nutrients being redistributed from leaves to seeds and a reduction in rate of …

Molybdenum Recommendation For Legumes, J. L. Sims, Warren C. Thompson, S. H. Phillips

Agronomy Notes

Molybdenum is recommended in Kentucky for legumes (soybeans, alfalfa, clovers and other forage legumes) beginning in 1969. The application should be made as a seed treatment and at the rate of 0.4 to 0.8 (4/10 to 8/10) ounces of molybdenum per acre. Molybdenum is recommended only on soils testing less than pH 6.2.

Fertilizing No-Tillage Corn And Soybeans, George D. Corder

Agronomy Notes

Planting corn and soybeans in sod (commonly referred to as "no-tillage" planting) is increasing in parts of Kentucky, and interest in this practice in other parts of the state is growing.

One question is often asked: 'What is the best method of liming and fertilizing no-tillage corn and soybeans?"

Since no-tillage planting is a comparatively new practice, only a limited amount of research on methods of fertilization has been done. However, research designed to find out how well plants can recover phosphorus and potassium applied on the surface of the soil will be started by the Department of Agronomy at …

Agronomy Notes, No. 1, S. H. Phillips, Harold F. Miller, Verne C. Finkner

Agronomy Notes

This is the first issue of "Agronomy Notes." The Agronomy Department, University of Kentucky, expects to use this publication to inform county agents, other agricultural workers, and leaders on current progress in soils & crops work. The Kentucky Experiment Station will be an important source of information. Information may be drawn from other research. Field trials and observations that show useful information may be reported. The emphasis will be on short timely topics.