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An Alfalfa Management Program For Optimum Yields And Quality, Bill Griffith Feb 1993

An Alfalfa Management Program For Optimum Yields And Quality, Bill Griffith

Kentucky Alfalfa and Stored Forage Conference

Alfalfa popularity is not surprising because it has the highest yield potential and the highest feeding value of all perennial hay crops. While the protein value of alfalfa is of major importance, its energy content is also high and should not be discounted. High yields of alfalfa harvested at the proper stage of maturity compare favorably with corn silage in production of energy.


Alfalfa Production And Trends In Kentucky, David D. Williamson Feb 1993

Alfalfa Production And Trends In Kentucky, David D. Williamson

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is often referred to as the "Queen of U.S. Forage Production". Looking at all hay production alfalfa should be called "The King". In 1991, 83.8 million tons were harvested in the United States -- 55 percent of all the hay harvested in the United States. This total does not include the many tons harvested as green chop, which is an especially common practice among dairy farmers. But, why shouldn't alfalfa be popular? This deep rooted leguminous plant is generally the forage leader in yield, protein, and TDN.


Foreword [1993], Garry D. Lacefield Feb 1993

Foreword [1993], Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

This is the front matter of the proceedings.


Shapes Of Venusian "Pancake" Domes Imply Episodic Emplacement And Silicic Composition, Jonathan H. Fink, Nathan T. Bridges, Robert E. Grimm Feb 1993

Shapes Of Venusian "Pancake" Domes Imply Episodic Emplacement And Silicic Composition, Jonathan H. Fink, Nathan T. Bridges, Robert E. Grimm

Geology Faculty Publications and Presentations

The main evidence available for constraining the composition of the large circular "pancake" domes on Venus is their gross morphology. Laboratory simulations using polyethylene glycol show that the height to diameter (aspect) ratios of domes given total volume depend critically on whether their extrusion was continuous or episodic, with more episodes leading to greater cooling and taller domes. Thus without observations of their emplacement, the compositions of venusian domes cannot be uniquely constrained by their morphology. However, by considering a population of 51 venusian domes to sent a sampling of many stages during the growth of domes with comparable histories, …


Geological Field Guide To The Cedar Point Biological Station, Keith County, Nebraska, Robert F. Diffendal Jr., Roger K. Pabian Feb 1993

Geological Field Guide To The Cedar Point Biological Station, Keith County, Nebraska, Robert F. Diffendal Jr., Roger K. Pabian

School of Natural Resources: Faculty Publications

This field guide was produced by staff members of the Conservation and Survey Division of the University of Nebraska originally in 1979 at the request of Dr. Brent Nickol, former Director of the Cedar Point Biological Station. It is an introduction to the geologic history and paleoecology of the Cedar Point area intended for students, staff, and other persons using the camp. This revision has been made some 15 years after the first version to reflect changes in ideas resulting from new data collected during that time.

Users of this guide should take care when studying the rock exposures described …


Calculation Of Acoustic Parameters By A Filter-Correlation Method, Robert C. Courtney, Larry A. Mayer Feb 1993

Calculation Of Acoustic Parameters By A Filter-Correlation Method, Robert C. Courtney, Larry A. Mayer

Affiliate Scholarship

This paper presents the filter correlation method, a technique for extracting consistent and accurate estimates of attenuation parameters from acoustic waveform data. The method minimizes problems associated with short time windows and multipath secondary arrivals. The method comprises two stages: a causal passband filter stage followed by a cross-correlation step. The results of the filter-correlation estimator are compared to those of the spectral difference approach for short time series with and without a secondary multipath arrival. Preliminary analyses of acoustic data collected on cored marine silts and clays show the attenuation properties of these materials cannot be described by a …


The Origin And Evolution Of The Southern Snake Range Decollement, East Central Nevada, Allen J. Mcgrew Feb 1993

The Origin And Evolution Of The Southern Snake Range Decollement, East Central Nevada, Allen J. Mcgrew

Department of Earth, Environment and Sustainability Faculty Publications

Regional and local stratigraphic, metamorphic, and structural constraints permit reconstruction of the southern Snake Range extensional deformational system in east central Nevada. The dominant structure of the range, the southern Snake Range décollement (SSRD), operated during Oligocene and Miocene extensional deformation to exhume a footwall of multiply deformed metasedimentary and plutonic rocks. Intrusion of three plutons (∼160 Ma, 79.1 ± 0.5 Ma, and 36 ± 1 Ma, respectively) and development of two cleavages preceded the onset of extensional deformation. Plastic deformation of lower plate metasedimentary rocks accompanied the early phases of regional extension and produced bedding-parallel grain shape foliations and …


Conservation For Production : Kings Rocks Catchment Report, William Oldfield Feb 1993

Conservation For Production : Kings Rocks Catchment Report, William Oldfield

Agriculture reports

The aim of this report is to bring together current information on the land and ideas which will provide landholders of the King Rocks catchment group with a basis to make more informed decisions about managing the land. The report contains information on how the landscape was formed, how areas become degraded, what are the present recommended ways of fixing land degradation and what are the most productive means of farming the land.


Dolomite Cement Stratigraphy Of The Reelfoot Rift And The Relationship Of These Cements To Dolomite Cements Found In Southeast Missouri, Timothy James Keller Jan 1993

Dolomite Cement Stratigraphy Of The Reelfoot Rift And The Relationship Of These Cements To Dolomite Cements Found In Southeast Missouri, Timothy James Keller

Opportunities for Undergraduate Research Experience Program (OURE)

The formation of the southeast Missouri Mississippi Valley-type Pb, Zn, Cu ore districts have been a subject of controversy. Using petrology and geochemistry, earlier studies have attempted to reveal fluid flow, composition, and origin of the ore forming fluids. In this study, the potential role of the Reelfoot rift (New Madrid seismic zone) as a source and/or conduit for ore forming fluids is addressed. By observing cuttings and cores from four oil test wells within the Reelfoot rift using cathodluminescence, four cement types were described: 1) A multiple generation cement type similar to that observed associated with mineralization in southeastern …


Depositional Facies Analysis And Sea Level Curve Determination From The Soth Western St. Francois Mts. To The Western Margin Of The Reelfoot Rift, Missouri, Aaron Ramon Rezendez Jan 1993

Depositional Facies Analysis And Sea Level Curve Determination From The Soth Western St. Francois Mts. To The Western Margin Of The Reelfoot Rift, Missouri, Aaron Ramon Rezendez

Opportunities for Undergraduate Research Experience Program (OURE)

Knowledge of the relative influence of eustatic and tectonic controls on sedimentation in basins is important to developing a regional facies model. The Reelfoot Rift basin is located on the southern margin of the North American Craton. The tectonic and sedimentary history of the rift began during Middle Cambrian time and extended through the Early Ordovician. Oil test well cuttings and cores were used to construct a stratigraphic fence extending from the Cambro- Ordovician platform west of the St. Francois Mts. southeastward info the rifted basin. Three major transgressive-regressive sequences and numerous minor transgressive-regressive sequences were observed in Cambro-Ordovician rocks …


Soil Testing: Field, Sample And Laboratory Variability, Lloyd W. Murdock, Dan Kirkland, Phil Gillespie, Tim Gray Jan 1993

Soil Testing: Field, Sample And Laboratory Variability, Lloyd W. Murdock, Dan Kirkland, Phil Gillespie, Tim Gray

Soil Science News and Views

Soil testing has advanced as a science and has become a tool widely used in making fertilizer recommendations. One of the basic components for ensuring reliability of recommendations is calibration of soil test results to determine the proper match of fertilizer recommendations with the soil test level for each nutrient and crop. Generally, calibration has been accomplished on small plot areas and is quite accurate. Even though there is nutrient variability within small areas, the potential for variability is much greater on a field basis. An important factor in making reliable fertilizer recommendations is the assumption that the soil sample …


Factors Affecting Color Of Cured Burley Leaf, J. L. Sims, Gary K. Palmer, Kenneth L. Wells Jan 1993

Factors Affecting Color Of Cured Burley Leaf, J. L. Sims, Gary K. Palmer, Kenneth L. Wells

Soil Science News and Views

Much interest has been shown by tobacco growers during recent months in fertilization and or other management practices that can be used to produce darker and redder cured leaf of burley tobacco. The purpose of this newsletter is to summarize what we know about some of the factors which affect color of cured leaf.


Upper Cretaceous Dinosaurs From The Blufftown Formation, Western Georgia And Eastern Alabama, David R. Schwimmer Jan 1993

Upper Cretaceous Dinosaurs From The Blufftown Formation, Western Georgia And Eastern Alabama, David R. Schwimmer

Faculty Bibliography

No abstract provided.


Managing Bushland On The Farm, Penny Hussey Jan 1993

Managing Bushland On The Farm, Penny Hussey

Journal of the Department of Agriculture, Western Australia, Series 4

Since the time of European settlement in Western Australia, the replacement of native vegetation with crops and pastures has led to problems for both agricultural production and nature conservation. The most obvious of these are hydrological changes leading to salinisation and waterlogging, and the extinction of some native plants and animals.

Protection of remaining remnants of native bushland, together with revegetation, is increasingly seen as important ways of achieving sustainable agriculture and maintaining our unique wildlife.


Establishment Of Lupin Seedlings, Miles Dracup Jan 1993

Establishment Of Lupin Seedlings, Miles Dracup

Journal of the Department of Agriculture, Western Australia, Series 4

Good seedbed conditions lead to high and rapid seedling emergence and vigorous seedlings best equipped to avoid disease, weed competition and sand-blasting. Good establishment is needed for a high yielding crop.

In Western Australia, seedbed moisture and temperature are most likely to limit successful emergence of lupins, especially with the trend toward early sowing.

Research by the Department of Agriculture is helping to define seedbed temperature and moisture requirements for successful lupin establishment that will help future research for improving seedbed conditions.


Flooding Of The Sinking Creek Karst Area In Jessamine And Woodford Counties, Kentucky, James C. Currens, C. Douglas R. Graham Jan 1993

Flooding Of The Sinking Creek Karst Area In Jessamine And Woodford Counties, Kentucky, James C. Currens, C. Douglas R. Graham

Report of Investigations--KGS

Tashamingo Subdivision in Sinking Creek Karst Valley, a tributary of the Garretts Spring Drainage Basin in Jessamine and Woodford Counties, Kentucky, was flooded in February 1989. To determine the cause of flooding, the boundary of the ground-water basin was mapped, discharge data were measured to determine intake capacity of swallow holes, and hydrologic modeling of the basin was conducted. Swallow-hole capacity was determined to be limited by the hydraulic parameters of the conduit, rather than by obstruction by trash. Flooding from a precipitation event is more likely, and will be higher, when antecedent soil moisture conditions in the watershed are …


Predicting Regeneration Establishment With The Prognosis Model, United States Department Of Agriculture, Forest Service Jan 1993

Predicting Regeneration Establishment With The Prognosis Model, United States Department Of Agriculture, Forest Service

Forestry

Conifer establishment following regeneration timber harvests is predicted by version 2 of the Regeneration Establishment Model, a submodel of the Prognosis Model. The regeneration model covers 10 species for forests in Montana, central Idaho, and northern Idaho. Most harvest and site preparation methods can be simulated so that alternative treatments can be evaluated. Also included in the model is the influence of western spruce budworm (Choristoneura accidentalis) on regeneration success. The model predicts the probability of stocking, seedling density, species composition, and seedling heights 2 to 20 years after harvest. This paper describes the study design, equation development, model formulation, …


Application Of Sealevel Stratigraphy To Neogene Great Plains Stratigraphy, Robert F. Diffendal Jr., A. Lowrie Jan 1993

Application Of Sealevel Stratigraphy To Neogene Great Plains Stratigraphy, Robert F. Diffendal Jr., A. Lowrie

Robert F. Diffendal, Jr., Publications

Absolute-dated high frequency (Milankovitch cycles) marine climate/sealevel oscillatory stratigraphy can be correlated generally with continental stratigraphies. Improvements in absolute dating of Neogene formations across the North American Great Plains make this a candidate area in which to correlate marine and continental stratigraphies. Mid-latitude continental areas respond directly to climate variations. During glaciated/ cold climates, sealevel lowering results in steepened river gradients, increased erosion all along the river channel, and larger stress-bed loads. This, combined with glacial catastrophic flooding, produces greater cut-and-fill sequences along river systems than crevasse splays along the emergent coastal plain, deltas along the shelf, and submarine fans …


Seismic Stratigraphy Of The Ontong Java Plateau, David Mosher, Larry A. Mayer, Tom H. Shipley, Edward L. Winterer, Rick A. Hagen, Janice C. Marsters, Frank Bassinot, Roy H. Wilkens, Mitchell Lyle Jan 1993

Seismic Stratigraphy Of The Ontong Java Plateau, David Mosher, Larry A. Mayer, Tom H. Shipley, Edward L. Winterer, Rick A. Hagen, Janice C. Marsters, Frank Bassinot, Roy H. Wilkens, Mitchell Lyle

Affiliate Scholarship

The Ontong Java Plateau, a large, deep-water carbonate plateau in the western equatorial Pacific, is an ideal location for studying responses of carbonate sedimentation to the effects of changing paleoceanographic conditions. These carbonate responses are often reflected in the physical properties of the sediment, which in turn control the appearance of seismic reflection profiles. Seismic stratigraphy analyses, correlating eight reflector horizons to each drill site, have been conducted in an attempt to map stratigraphic data. Accurate correlation of seismic stratigraphic data to drilling results requires conversion of traveltime to depth in meters. Synthetic seismogram models, using shipboard physical properties data, …


Laboratory And Well-Log Velocity And Density Measurements From The Ontong Java Plateau: New In-Situ Corrections To Laboratory Data For Pelagic Carbonates, Jozsef Urmos, Roy H. Wilkens, Frank Bassinot, Mitchell Lyle, Janice C. Masters, Larry A. Mayer, David Mosher Jan 1993

Laboratory And Well-Log Velocity And Density Measurements From The Ontong Java Plateau: New In-Situ Corrections To Laboratory Data For Pelagic Carbonates, Jozsef Urmos, Roy H. Wilkens, Frank Bassinot, Mitchell Lyle, Janice C. Masters, Larry A. Mayer, David Mosher

Affiliate Scholarship

During Ocean Drilling Program Leg 130, sonic velocity and bulk density/porosity well logs were measured in five separate holes drilled through the sequence of pelagic carbonate oozes, chalks, and limestones that comprise the thick, continuous sedimentary cover on the Ontong Java Plateau. An internally consistent and continuous suite of shipboard laboratory velocity and sediment physical properties measurements were made from the top of each hole down through the entire logged interval. Because of the high quality of the data, extensive overlap of 500 m or more between the log and laboratory measurements at each hole, and the homogeneous nature of …


Variations Of Porosity In Calcareous Sediments From The Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens Jan 1993

Variations Of Porosity In Calcareous Sediments From The Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens

Affiliate Scholarship

Based on index properties measurements made on board the JOIDES Resolution, we studied porosity changes with depth in the fairly homogeneous deep-sea calcareous sediments cored during Ocean Drilling Program Leg 130 on the Ontong Java Plateau. Using Leg 130 data, we present evidence that the rate of porosity decrease with burial in calcareous oozes and chalks is related to the depth of deposition and thus probably depends on the "conditioning" of calcareous sediments by winnowing or dissolution processes during the time of deposition. The ooze-to-chalk transition is not clearly reflected in porosity profiles. In the ooze-chalk sections studied (the upper …


Climatic Cyclicity At Site 806; The Grape Record, Larry A. Mayer, Eystein Jansen, Jan Backman, Toshiaki Takayama Jan 1993

Climatic Cyclicity At Site 806; The Grape Record, Larry A. Mayer, Eystein Jansen, Jan Backman, Toshiaki Takayama

Affiliate Scholarship

We used the continuous saturated bulk density records collected by the gamma-ray attenuation porosity evaluator (GRAPE) at Ocean Drilling Program Site 806 on the top of the Ontong Java Plateau to evaluate the continuity of the recovered cores and to splice together a complete section from the multiple holes drilled at the site (for the upper 165 m, this is equivalent to approximately 0-5 Ma). The lack of offset in core breaks (between the 9.5-m-long, successive cores) from hole to hole made splicing difficult, and the results are not unambiguous. The composite section was converted to a time series by …


North Stirling Land Conservation District - Soils Manual, Justin Hardy, Peter J. Tille Jan 1993

North Stirling Land Conservation District - Soils Manual, Justin Hardy, Peter J. Tille

Soil conservation survey collection

The North Stirling Land Conservation District is located between Katanning and Albany on the northern edge of the Stirling Ranges in south-western Western Australia.It includes parts of the Shires of Cranbrook and Tambellup, covering approximately 100,000ha of the catchment of the North Stirling basin. The basin is a flat area formed on Eocene sediments with poorly defined drainage lines and many salt lakes. It is surrounded by low granite and sandstone hills. The climate is Mediterranean, with cool wet winters and hot dry summers. Average annual rainfall ranges from 375-500 mm per annum. There is very little surface or underground …


Amblyrhiza And The Vertebrate Paleontology Of Anguillean Caves, Donald A. Mcfarlane, Ross D. E. Macphee Jan 1993

Amblyrhiza And The Vertebrate Paleontology Of Anguillean Caves, Donald A. Mcfarlane, Ross D. E. Macphee

WM Keck Science Faculty Papers

Recorded interest in the caves of Anguilla dates back to the second half of the nineteenth century. The earliest explorations were concerned with the locating phosphatic cave earths, and resulted in the mining of several sites. Incidental to this work, the bones of the largest island rodent ever discovered were collected from Aguillan caves. Whereas the phosphate mining operations were short-lived, the remains of the giant rodent Amblyrhiza have catalyzed a continued interest in the caves of Anguilla. The most recent series of explorations have provided the first adequate documentation of Amhlyrhiza fossil sites, and have started to yield radiometric …


A Versatile Shotgun Source For Engineering And Groundwater Seismic Surveys, John R. Pelton Jan 1993

A Versatile Shotgun Source For Engineering And Groundwater Seismic Surveys, John R. Pelton

CGISS Publications and Presentations

We describe an electrical seismic gun that is capable of firing 8-gauge blank black powder shells in a water-filled borehole under relatively high hydrostatic pressures. The new seismic gun is a modified version of the electrical shotgun source for engineering seismic surveys introduced by Pullan and MacAulay (1987). Our modifications seal the firing circuit and 8-gauge shell against water entry so underwater detonation will occur reliably at depths to at least 80 m (0.9 MPa atmospheric pressure). Source energy is controlled by varying the size of the black powder load in the shell from 50 grains to 500 grains (10 …


Bowling Green Lady Left Her Mark On Kentucky’S Oil Industry, Jonathan Jeffrey Jan 1993

Bowling Green Lady Left Her Mark On Kentucky’S Oil Industry, Jonathan Jeffrey

SCL Faculty and Staff Publications

Margaret Morehead Hobson (1890-1987), a native of Bowling Green, Kentucky, worked for over fifty years in the oil and gas industry in western Kentucky. This biographical article examines her life and contributions to the predominantly male field of geological exploration.


Evolution Of Pliocene Climate Cyclicity At Hole 806b (5-2 Ma); Oxygen Isotope Record, Eystein Jansen, Larry A. Mayer, Jan Backman, R. Mark Leckie, Toshiaki Takayama Jan 1993

Evolution Of Pliocene Climate Cyclicity At Hole 806b (5-2 Ma); Oxygen Isotope Record, Eystein Jansen, Larry A. Mayer, Jan Backman, R. Mark Leckie, Toshiaki Takayama

Affiliate Scholarship

A detailed Pliocene oxygen isotope record from the Ontong Java Plateau, based on measurements of the surface-dwelling planktonic foraminifer Globigerinoides sacculifer, was produced for the period from 5 to 2 Ma. The record documents major long and short-term climate changes. The results show periods of enhanced ice volume at 4.6 to 4.3 Ma and after 2.85 Ma, a long-term warming trend from 4.1 to 3.7 Ma, and a distinct cooling trend that was initiated at 3.5 Ma and progressed through the initiation of large-scale Northern Hemisphere glaciation after 2.85 Ma (according to the time scale of Shackleton and others proposed …


Detailed Stratigraphic Correlation Of The Neogene Sedimentary Sequences On The Ontong Java Plateau By Well Logging; Odp Sites 803, 805, 806, 807, And Dsdp Site 586, Mitchell Lyle, Roy H. Wilkens, Larry A. Mayer Jan 1993

Detailed Stratigraphic Correlation Of The Neogene Sedimentary Sequences On The Ontong Java Plateau By Well Logging; Odp Sites 803, 805, 806, 807, And Dsdp Site 586, Mitchell Lyle, Roy H. Wilkens, Larry A. Mayer

Affiliate Scholarship

We used well logs, in some cases combined with shipboard physical properties measurements to make more complete profiles and to correlate between sites on the Ontong Java Plateau. By comparing sediment bulk density, velocity, and resistivity logs from adjacent holes at the same site, we showed that even subtle features of the well logs are reproducible and are caused by variations in sedimentation. With only minor amounts of biostratigraphic information, we could readily correlate these sedimentary features across the entire top of the Ontong Java Plateau, demonstrating that for most of the Neogene the top of the plateau is a …


Velocity Anisotropy In Calcareous Sediments From Leg 130, Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens Jan 1993

Velocity Anisotropy In Calcareous Sediments From Leg 130, Ontong Java Plateau, Frank Bassinot, Janice C. Marsters, Larry A. Mayer, Roy H. Wilkens

Affiliate Scholarship

During Leg 130, an intensive program of P-wave velocity measurements was conducted on calcareous sediments of varying induration (ranging from ooze to limestone) that cover the Ontong Java Plateau (west equatorial Pacific). The high quantity and quality of shipboard acoustical property measurements seemed to be particularly appropriate for gaining a better understanding of acoustic anisotropy in calcareous sediments. Major results can be summarized as follows: 1. In calcareous oozes, acoustic anisotropy exists even at shallow depths of burial. Values are low, ranging from -0.5% to 3.5% and averaging 1.2%. Anisotropy profiles are affected by coring disturbances, but they still roughly …


Basement Structure Of The Northern Ontong Java Plateau, Rick A. Hagen, Larry A. Mayer, David Mosher, Loren W. Kroenke, Tom H. Shipley, Edward L. Winterer Jan 1993

Basement Structure Of The Northern Ontong Java Plateau, Rick A. Hagen, Larry A. Mayer, David Mosher, Loren W. Kroenke, Tom H. Shipley, Edward L. Winterer

Affiliate Scholarship

Site surveys conducted in conjunction with Leg 130 on the Ontong Java Plateau reveal a strong seismic reflector at 0.8 to 1.0 s below the seafloor that drilling at Sites 803 and 807 confirmed is Cretaceous basalt. This reflector is generally smooth, except for the northeastern margin of the plateau, where it forms a series of small, irregularly shaped depressions. Correlatable reflectors present at the bottom of the depressions are also present on the adjacent highs, suggesting that these depressions are original volcanic topography. A strong sub-basalt reflector occurs on many seismic profiles on the northeastern portion of the plateau. …