Physical Sciences and Mathematics Commons^™

Optically Thin Broad-Line Clouds In Active Galactic Nuclei, Joseph C. Shields, Gary J. Ferland, Bradley M. Peterson

Physics and Astronomy Faculty Publications

The broad-line region (BLR) in Seyfert galaxy nuclei exhibits correlated variations in continuum and emission-line luminosity that are qualitatively consistent with photoionization of ionization-bounded (optically thick) clouds. However, evidence is growing that a nonnegligible fraction of the BLR cloud population is optically thin to the Lyman continuum and fully ionized in hydrogen. We consider the implications of this nebular component for observed line emission and find that inclusion of thin clouds in photoionization calculations can resolve several outstanding puzzles of Seyfert variability, notably the behavior of the C IV λ1549/Lyα ratio as a function of continuum luminosity.

A …

What Leading Alfalfa Growers Do To Produce Quality Hay, Jimmy C. Henning, Garry D. Lacefield, Buddy Sims

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is the highest quality forage legume crop grown in Kentucky and is the number one cash hay crop. Hay raised by Kentucky farmers has been recognized for its quality at local, state (state fair and Kentucky Alfalfa Conference), and national (American Forage and Grassland Council) hay contests. The testing records of the Kentucky Department of Agriculture also document the high quality alfalfa hay of Kentucky. However, little has been written about the farm practices used to produce high quality alfalfa hay in Kentucky. The current practices of top hay growers may be helpful in defining the options available to …

How To Make Your Alfalfa More Profitable, Clive Holland

Kentucky Alfalfa and Stored Forage Conference

As a perennial plant, alfalfa can be expected to continue to live and produce for an indefinite period of time. Why then do stands need to be replanted every few years? Is modern seed available today, weakened and unable to live up to the perennial label? What about yield? How does your stand measure up? Are you barely making the state average, or struggling to even meet this modest yield level?

The first harvest each spring can produce over 40% of the yield in a single growing season. Why is a stand slower growing in the spring than you would …

Role Of Alfalfa In Animal Diets, Jennifer L. Garrett

Kentucky Alfalfa and Stored Forage Conference

Alfalfa forage use has increased in all classes of livestock - dairy, beef, horses, sheep, and swine - during the last 40 years. The highest utilization of alfalfa by livestock is found in dairy cattle diets. Additionally, the use of alfalfa as a grazing crop has also undergone a considerable increase with the use of new grazing management techniques and the development of new grazing varieties.

Alfalfa's strength as a forage crop is its high nutritional value. Alfalfa is higher in protein, minerals, and net energy than grasses and small grains. High quality alfalfa also helps to promote intake, especially …

Saving Those Valuable Leaves During Haymaking, Michael Collins

Kentucky Alfalfa and Stored Forage Conference

Field dry hay needs to be reduced from near 80% moisture to 20% or less to prevent spoilage during storage. Drying hay to safe baling moistures often takes several days. Sources of loss during forage harvest include mechanical losses such as mowing, conditioning, chopping, raking, packaging and handling as well as respiration and leaching. The general relationship between forage moisture concentration at harvest and losses during the field and storage phases is shown in Figure 1. Harvest losses are greatest for very dry forage and are low for very wet material like direct cut silage. However, the latter is subject …

Alfalfa As A Grazing Crop: Progress Continues, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

This makes the third consecutive year that I have talked about "Alfalfa as a Grazing Crop". At our XIII Kentucky Alfalfa, I, along with five other speakers, discussed several aspects of grazing alfalfa and all agreed that the concept had tremendous potential.

This past year I reviewed some of the discussion of our XIII Conference and shared some of the activities going on in research and educational programs throughout the region. In addition, I announced the date for a National Alfalfa Grazing Conference to be held in Nashville, Tennessee. The Conference was held July 29 and was a big success. …

Control Of Johnsongrass And Other Weedy Grasses In Alfalfa, Jonathan D. Green

Kentucky Alfalfa and Stored Forage Conference

Johnsongrass is considered one of the major weed species that infests alfalfa in Kentucky. Other weedy grasses such as large crabgrass, foxtails, barnyard grass, and fall panicum can also interfere with alfalfa production. Low infestation levels of these grasses may not create significant concern, but high infestation levels can result in reduced yield, alfalfa hay quality, and/or shorten the life of the stand.

Opportunities For No-Till Alfalfa In Kentucky, Jimmy C. Henning, Garry D. Lacefield, Andy Anderson

Kentucky Alfalfa and Stored Forage Conference

There is a rising interest in the use of alfalfa in pastures, especially for dairy cattle, beef stockers and as supplemental summer grazing for cows with calves. Kentucky has the land resource to support 2 million acres of alfalfa without reducing acres in cultivated crops. Acres of alfalfa seeded for pasture use would be in addition to the 350,000 acres presently used primarily for hay. However, these additional acres are rolling and erodible and therefore alfalfa should be established by no-till methods.

Establishing Alfalfa Following Alfalfa: How Long Do We Wait?, Monroe Rasnake

Kentucky Alfalfa and Stored Forage Conference

It has long been recommended that alfalfa fields be rotated to another crop such as com for at least one growing season before reestablishing alfalfa. One reason for doing this is that insect and disease levels build up in the old alfalfa and this time is needed to allow them to die out. Another reason is that alfalfa plants have been shown to produce compounds that inhibit the germination and growth of new alfalfa seedlings. This is called autotoxicity or allelopathy.

Recently researchers from other states have indicated that it may not be necessary to have a full growing season …

Foreword [1995], Garry D. Lacefield, Christi L. Forsythe

Kentucky Alfalfa and Stored Forage Conference

This is the front matter of the proceedings.

On The Current Status Of Maser Polarization Theory, Moshe Elitzur

Physics and Astronomy Faculty Publications

Despite recent criticism, past conflicts among theoretical studies of maser polarization are by now resolved and clarified. All analytical methods proposed thus far produce the same polarization solutions, solutions that agree with observations. Current numerical studies do not reproduce these solutions. Instead, for any pumping employed, their results are in direct conflict with both analytical theory and observations. These problems reflect the fact that the basic formulation of numerical modeling has yet to incorporate the statistical nature of the radiation field.

Grains In Ionized Nebulae: Spectral Line Diagnostics, J. B. Kingdon, Gary J. Ferland, W. A. Feibelman

Physics and Astronomy Faculty Publications

The depletion of condensable elements onto grains in gaseous nebulae can provide evidence that dust is well mixed with the ionized gas. Al and CA are two of the most depleted elements in the general interstellar medium, and it is therefore important to measure their abundances within the ionized region of nebulae. We compute a large grid of photoionization models and identify sets of line ratios which are relatively insensitive to stellar and nebular parameters, and are thus excellent diagnostics for determining relative abundances. Based on the absence of the [Ca II] λλ7291, 7324 doublet and the detection of …

The Origin Of N Iii Λ990 And C Iii Λ977 Emission In Agn Narrow-Line Region Gas, Jason W. Ferguson, Gary J. Ferland, A. K. Pradham

Physics and Astronomy Faculty Publications

We discuss implications of Hopkins Ultraviolet Telescope (HUT) detections of C III λ977 and N III λ990 emission from the narrow-line region of the Seyfert 2 galaxy NGC 1068. In their discovery paper Kriss et al. showed that the unexpectedly great strength of these lines implies that the emitting gas must be shock-heated if the lines are collisionally excited. Here we investigate other processes which excite these lines in photoionization equilibrium. Recombination, mainly dielectronic, and continuum fluorescence are strong contributors to the line. The resulting intensities are sensitive to the velocity field of the emitting gas and require …

Interpreting Soils Maps, Kenneth L. Wells

Soil Science News and Views

A knowledge of the nature andaracteristics of soils on a farm is basic to farm planning so as to properly match crops and soils and minimize the effect of soil variation on crop production and economic return. This information also provides a realistic basis for estimating crop yields on a field-by-field basis, a planning step necessary in estimating anticipated costs and returns. Detailed soils maps which have been prepared by soil scientists identify the various soil series which occur on the landscape, and show the slope of the landscape on which they occur, as well as the amount of topsoil …

An Assessment Of Water Sources Related To Major Systems Of Agricultural Land Use In Kentucky, Robert L. Blevins, Gerald R. Haszler, Grant W. Thomas, Kenneth L. Wells, William W. Witt

Soil Science News and Views

Recent years have seen a greater public concern about the quality of the nation's water resources. While initial concerns targeted point source pollution, the emphasis in recent years has shifted to non-point source pollution, including the effect of general practices used by fanners in agricultural production systems. Since there was no reliable data base on such effects for Kentucky, the state's General Assembly passed legislation during its 1990 session directing the University ofKentucky's College of Agriculture (UK.CA) to assess the effect of agricultural practices on quality of the state's waters. As part of the efforts undertaken by the UKCA in …

Returning Crp Land To Grain Production, Wilbur Frye, Lloyd W. Murdock

Soil Science News and Views

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 …

No Tillage Adoption In Grain Crops In Kentucky Counties In 1994, Gerald R. Haszler, Grant W. Thomas

Soil Science News and Views

The no-tillage system, where soils are neither tilled nor cultivated, has a number of advantages. Studies in Kentucky and in other states show much lower erosion under no tillage as compared with conventional tillage. In addition, fuel, machinery, and time savings are all impressive when the no-tillage system is used. There is also a tendency toward better crop yields due to higher water capture and/or conservation that is associated with the mulch of crop residues that is maintained on the soil surface in no tillage.

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 …

Weed Seed In Poultry Litter: Should Farmers Be Concerned, Monroe Rasnake

Soil Science News and Views

Over the years, I have received many calls from farmers who have had unusual weed problems in their fields. Their first thoughts normally are that weed seeds were brought to the fields in crop seed, hay, manure, etc. Some of the same concern has been expressed in regard to using poultry litter on fields. As poultry litter becomes available to more Kentucky farmers, should they be concerned about the possibility it would contain weed seed? The simple answer to the question is "NO" in most situations.

The Effect Of Organic Matter On Maximum Compactability Of Soil, Grant W. Thomas, Gerald R. Haszler, Robert L. Blevins

Soil Science News and Views

Bulk density is the weight of a given volume of soil expressed by soil scientists as grams per cubic centimeter (g/cm3). The higher the bulk density, the lower the volume of soil occupied by pore space, that volume of soil in which air and water reside. Because of this, there is much interest on the degree to which soil can be compacted.

The Proctor test is a means of determining the maximum bulk density that can be attained in a soil sample. This "maximum compactibility" is widely used on highways and building foundations but has had little use in agricultural …

The Effect Of Rate And Source Of Potassium Fertilizer On Cured Leaf Yield Of Burley Tobacco And Leaf Content And Soil Test Levels Of Potassium And Magnesium, Kenneth L. Wells, James E. Dollarhide, Mark Reese

Soil Science News and Views

In response to questions being asked by tobacco growers about the effectiveness of sulfate of potash magnesia (SPM; 21% K₂O and 11% Mg) as coinpared to sulfate of potash (SP; 50% K₂O), field studies were conducted during 1993-1994 to compare the two potassium (K) sources for use on burley tobacco. Any effect of SPM on yield of tobacco should be due to Mg since the only difference between the two sources in kind of nutrient contained is the presence of magnesium (Mg) in SPM. To compare the two K sources, we selected field sites low enough …

High-Carbonate, Low-Silica, High-Calcium Stone In The High Bridge Group (Upper Ordovician), Mason County, North-Central Kentucky, Warren H. Anderson, Lance S. Barron

Information Circular--KGS

The High Bridge Group (Middle Ordovician) of northeastern Kentucky is a major source of limestone and dolomite for construction, agricultural, and industrial stone. These industries require carbonate rocks of high chemical purity. Chemical analyses of foot-by-foot samples from a Mason County core show that three zones of high-calcium and several thick zones of high-carbonate and low-silica stone are present in the High Bridge at a mineable depth. Mason County is located in northeastern Kentucky, on the Ohio River, and offers river access to transportation to the metropolitan Covington-Cincinnati market and the northern portion of the Eastern Kentucky Coal Field for …

Effectiveness Of Vegetative Filter Strips In Controlling Losses Of Surface-Applied Poultry Litter Constituents, Indrajeet Chaubey, Dwayne R. Edwards, Tommy C. Daniel, Philip A. Moore Jr., D. Jeff Nichols

Biosystems and Agricultural Engineering Faculty Publications

Vegetative filter strips (VFS) have been shown to have high potential for reducing nonpoint source pollution from cultivated agricultural source areas, but information from uncultivated source areas amended with poultry litter is limited. Simulated rainfall was used in analyzing effects of VFS length (0, 3.1, 6.1, 9.2, 15.2, and 21.4 m) on quality of runoff from fescue (Festuca arundinacea Schreb.) plots (1.5 x 24.4 m) amended with poultry litter (5 Mg/ha). The VFS reduced mass transport of ammonia-nitrogen (NH₃-N), total Kjeldahl nitrogen (TKN), ortho-phosphorus (PO₄-P), total phosphorus (TP), chemical oxygen demand (COD), and total suspended …

Atrazine And Alachlor Dissipation Rates From Field Experiments, Stephen R. Workman, Andrew D. Ward, Norman R. Fausey, Sue E. Nokes

Biosystems and Agricultural Engineering Faculty Publications

Chemical transport is being monitored in the root zone of three agricultural management systems at the Ohio Management Systems Evaluation Area (OMSEA). Atrazine and alachlor concentration data from soil cores taken to a depth of 0.9 m and partitioned into the increments of 0.0 to 0.15, 0.15 to 0.3, 0.45 to 0.6, and 0.75 to 0.9 m show the herbicides remained in the top 0.15 m of the profile during the 1991 and 1992 growing seasons. The slow movement of herbicides was partly due to below normal rainfall during the period. Since the herbicides have not been transported out of …

Regional Variation In Temperature Humidity Index For Poultry Housing, Richard S. Gates, Hanzhong Zhang, Donald G. Colliver, Douglas G. Overhults

Biosystems and Agricultural Engineering Faculty Publications

A building thermal model was used to compute hourly values of temperature humidity index (THI) for a broiler house with and without an evaporative misting system. Hourly summer time weather data for 238 U.S.A. locations covering 30 years were used to develop extreme occurrences of THI. Results were incorporated into a Geographical Information System (GIS) database to create isolines of THI and percentage of hours exceeding a heat stress threshold. Regional variations in misting as a suitable cooling technique are presented in terms of hours reduction in annual heat stress. The technique may be used for assisting in management decisions …

Distribution Of Oil And Gas Wells In Kentucky, Brandon C. Nuttall, Daniel I. Carey

Map and Chart--KGS

This map shows the distribution of more than 109,000 wells for which location information is available in the Kentucky Geological Survey's oil and gas well record database.

Bouguer Gravity Map Of Kentucky, G. Randy Keller, Donald C. Adams

Map and Chart--KGS

No abstract provided.

Potential Agronomic Benefits Of Wood Ash Application On Reclaimed Surface Mined Lands, David C. Ditsch, John H. Grove, William O. Thom

Soil Science News and Views

Wood ash is a by-product generated by paper companies, lumber manufacturing plants and utilities that bum wood products, bark and papermill sludge as a means of disposal and/or energy production. Large quantities of wood ash are generated by these industries since wood generally contains 6 to 10% ash. Most of these ashes are landfilled or discarded in lagoons. However, the increasing expense of landfill disposal has led to increased interest in the land application of industry generated wood ash.

Effects Of Longwall Mining On Hydrogeology, Leslie County, Kentucky Part 1: Pre-Mining Conditions, Shelley A. Minns, James A. Kipp, Daniel I. Carey, James S. Dinger, Lyle V. A. Sendlein

Report of Investigations--KGS

An investigation of the hydrologic effects of longwall coal mining is in progress in the Eastern Kentucky Coal Field. The study area is located in a first-order watershed in southern Leslie County over Shamrock Coal Company's Beech Fork Mine (Edd Fork Basin on the Helton 7.5-minute quadrangle). Longwall panels approximately 700 feet wide are separated by three-entry gateways 200 feet wide. The mine is operating in the Fire Clay coal (Hazard No. 4); overburden thickness ranges from 300 to 1,000 feet. Mining in the watershed began in late summer 1993. Undermining of the instrumented panel (panel 7) is anticipated for …

Preliminary Map Of The Structure Of The Precambrian Surface In Eastern Kentucky, James A. Drahovzal, Martin C. Noger

Map and Chart--KGS

This preliminary interpretation of the Precambrian unconformity surface in eastern Kentucky is based on data available to the Kentucky Geological Survey (KGS) as of November 1994. In early 1995, additional data became available to the KGS. Subsequent work using the new data should result in a more complete interpretation of the area within the next several years.

The map illustrates the Rome Trough and associated structures of the Precambrian surface, and as such contributes to an understanding of the regional geology, geologic evolution, distribution of energy and mineral resources, and potential geologic hazards. While it cannot be considered a prospecting …