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Full-Text Articles in Physical Sciences and Mathematics

Vegetation Controls On Weathering Intensity During The Last Deglacial Transition In Southeast Africa, Sarah J. Ivory, Michael M. Mcglue, Geoffrey S. Ellis, Anne-Marie Lézine, Andrew S. Cohen, Annie Vincens Nov 2014

Vegetation Controls On Weathering Intensity During The Last Deglacial Transition In Southeast Africa, Sarah J. Ivory, Michael M. Mcglue, Geoffrey S. Ellis, Anne-Marie Lézine, Andrew S. Cohen, Annie Vincens

Earth and Environmental Sciences Faculty Publications

Tropical climate is rapidly changing, but the effects of these changes on the geosphere are unknown, despite a likelihood of climatically-induced changes on weathering and erosion. The lack of long, continuous paleo-records prevents an examination of terrestrial responses to climate change with sufficient detail to answer questions about how systems behaved in the past and may alter in the future. We use high-resolution records of pollen, clay mineralogy, and particle size from a drill core from Lake Malawi, southeast Africa, to examine atmosphere-biosphere-geosphere interactions during the last deglaciation (~ 18-9 ka), a period of dramatic temperature and hydrologic changes. The …


Kentucky Forage Spokesperson Contest, Kentucky Forage And Grassland Council Oct 2014

Kentucky Forage Spokesperson Contest, Kentucky Forage And Grassland Council

Kentucky Grazing Conference

No abstract provided.


Can I Afford To Spray For Weeds?, Scott Flynn Oct 2014

Can I Afford To Spray For Weeds?, Scott Flynn

Kentucky Grazing Conference

A common question among managers of grazing operations is “At what level of weed pressure does it become economical to apply herbicides on pastures?” Unfortunately there isn’t just one answer to this question as production goals and practices differ between operations and even within an operation over time. Regardless, the real question being ask is if weed control will increase profit per acre.


Grazing Options For Fall And Winter, Edward N. Ballard Oct 2014

Grazing Options For Fall And Winter, Edward N. Ballard

Kentucky Grazing Conference

Feed costs represent the major cost in most livestock production systems. A recently completed analysis of 225 Standardized Performance Analysis (SPA) Beef Cow Records on herds in Illinois and Iowa showed that feed cost was the overriding factor determining profitability, explaining over 57 percent of the herd-to-herd variation.


Summer Grazing Options, S. Ray Smith, Krista Lea Oct 2014

Summer Grazing Options, S. Ray Smith, Krista Lea

Kentucky Grazing Conference

During the last 15 years there have been several new forage species that have emerged as useful in grazing systems and many new varieties have been released of traditional species. There are many sources of information on summer grazing options. We especially encourage you to read the publication written by Dr. Garry Lacefield and colleagues, “Extending Grazing and Reducing Stored Feed Needs” (AGR-199, www.uky.edu/Ag/Forage/agr199.pdf). I have used information from this publication and other publications from the University of Kentucky Forage Website (www.uky.edu/Ag/Forage) in writing this article.


Technical Service Provider: What Is It And Why Is It Important To You?, Bill Payne Oct 2014

Technical Service Provider: What Is It And Why Is It Important To You?, Bill Payne

Kentucky Grazing Conference

Progressive graziers and forage managers are continually looking to improve their operations’ productivity. The opportunity exists to have a Grazing Management Plan developed for your operation at little or no cost to you. By contacting your county NRCS office, you can apply to have this plan developed by a Technical Service Provider, an independent professional certified by NRCS.


Forage Legumes: Their Importance And Management In Profitable Livestock Systems, Ben M. Goff Oct 2014

Forage Legumes: Their Importance And Management In Profitable Livestock Systems, Ben M. Goff

Kentucky Grazing Conference

The landscape of most Kentucky operations is heavily dominated by the utilization of cool-season grasses as the primary source of forage for livestock. However, legumes species, such alfalfa and red or white clovers are an essential component to a complete forage-livestock system. Relative to grasses alone, incorporating legumes into a mixture has the benefits of improving the nutritive value of the available forage in the field, extending the grazing season by increasing the yield of forage during the early summer months, and providing a more economical source of N compared to commercial fertilizers. This paper will briefly describe each of …


Maximizing Stocker Gains On Pastures, Jeff Lehmkuhler Oct 2014

Maximizing Stocker Gains On Pastures, Jeff Lehmkuhler

Kentucky Grazing Conference

Stocker enterprises by definition utilize pasture forages to add weight to light weight feeder cattle. These operations add value to calves by assimilating small groups of calves and combining them into larger uniform packages. Stocker operators also enhance quality through livestock husbandry practices that “upgrade” feeders which could include castrating bulls, dehorning, improving immunity and other attributes. In an effort to optimize profit margins, stocker operators must manage feeders to ensure high rates of gain while finding a balance in stocking rates that provide adequate gains per acre.


Grazing Method: Tool Or Toolbox?, Garry D. Lacefield Oct 2014

Grazing Method: Tool Or Toolbox?, Garry D. Lacefield

Kentucky Grazing Conference

This conference makes the 15th consecutive year we have devoted a full day to Grazing. Kentucky is a great state for grazing animals since we have a relatively long pasture season, can grow many forage grasses and legumes and a long tradition of producing quality animal products from quality pasture. We have tremendous potential to improve our overall grazing efficiency and the discussion throughout the day will address many of the practical strategies for improvements.


Foreword And Kfgc Award Winners [2014], Garry D. Lacefield, Christi L. Forsythe Oct 2014

Foreword And Kfgc Award Winners [2014], Garry D. Lacefield, Christi L. Forsythe

Kentucky Grazing Conference

No abstract provided.


Warming Reduces Tall Fescue Abundance But Stimulates Toxic Alkaloid Concentrations In Transition Zone Pastures Of The U.S., Rebecca L. Mcculley, Lowell P. Bush, Anna E. Carlisle, Huihua Ji, Jim A. Nelson Oct 2014

Warming Reduces Tall Fescue Abundance But Stimulates Toxic Alkaloid Concentrations In Transition Zone Pastures Of The U.S., Rebecca L. Mcculley, Lowell P. Bush, Anna E. Carlisle, Huihua Ji, Jim A. Nelson

Plant and Soil Sciences Faculty Publications

Tall fescue pastures cover extensive acreage in the eastern half of the United States and contribute to important ecosystem services, including the provisioning of forage for grazing livestock. Yet little is known concerning how these pastures will respond to climate change. Tall fescue's ability to persist and provide forage under a warmer and wetter environment, as is predicted for much of this region as a result of climate change, will likely depend on a symbiotic relationship the plant can form with the fungal endophyte, Epichloë coenophiala. While this symbiosis can confer environmental stress tolerance to the plant, the endophyte …


Northeast‐Oriented Transpression Structure In The Northern New Madrid Seismic Zone: Extension Of A Shear Zone Across The Reelfoot Fault Stepover Arm, Edward W. Woolery, Ali Almayahi Oct 2014

Northeast‐Oriented Transpression Structure In The Northern New Madrid Seismic Zone: Extension Of A Shear Zone Across The Reelfoot Fault Stepover Arm, Edward W. Woolery, Ali Almayahi

Earth and Environmental Sciences Faculty Publications

High‐resolution seismic‐reflection profiles recently acquired 12 km northeast of the New Madrid seismic zone’s Reelfoot thrust and along the central axis of the Reelfoot rift, imaged steeply dipping N30°E striking faults that have uplifted and arched post‐Paleozoic sediments in a manner consistent with a dextral strike‐slip component of displacement. The subparallel fault strands have been traced 1.4 km between reflection profiles. In order to evaluate the structure’s potential regional scale, the strike was projected northeast 22 km to its intersection with a nearby industry profile. At the intersection, this lower‐resolution profile exhibits a discrete 0.75 km wide structure with style …


The MW 4.2 Perry County, Kentucky, Earthquake Of 10 November 2012: Evidence Of The Eastern Tennessee Seismic Zone In Southeastern Kentucky, N. Seth Carpenter, Edward W. Woolery, Zhenming Wang Jul 2014

The MW 4.2 Perry County, Kentucky, Earthquake Of 10 November 2012: Evidence Of The Eastern Tennessee Seismic Zone In Southeastern Kentucky, N. Seth Carpenter, Edward W. Woolery, Zhenming Wang

Earth and Environmental Sciences Faculty Publications

The 10 November 2012 Mw 4.2 Perry County earthquake may represent a continuation of the seismically active Eastern Tennessee seismic zone (ETSZ) farther north than previously recognized into southeastern Kentucky. The mainshock and aftershock data from regional seismic networks and EarthScope’s Transportable Array stations allowed high‐quality determinations of the source parameters. The focal mechanism, depth, and proximity of the mainshock to the New York–Alabama magnetic lineament, a subsurface, crustal‐scale structure that spatially correlates with central ETSZ seismicity, suggest that this earthquake may share the same type of causal geologic structures as the more‐active ETSZ region to the south.


Photo Highlights From The 34th Kentucky Alfalfa Conference, Kentucky Alfalfa Conference Feb 2014

Photo Highlights From The 34th Kentucky Alfalfa Conference, Kentucky Alfalfa Conference

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


Adjustments And Maintenance Of Haying Equipments, Clayton Geralds, John Mccoy, Cris Scudder Feb 2014

Adjustments And Maintenance Of Haying Equipments, Clayton Geralds, John Mccoy, Cris Scudder

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


Advances In Alfalfa Promotion, Bill Talley Feb 2014

Advances In Alfalfa Promotion, Bill Talley

Kentucky Alfalfa and Stored Forage Conference

Kentucky grain farmers have experienced several successful years seeing high prices and good yields, with the exception of the drought in 2012. If you were insured in 2012, which most lenders required, you probably also came out with a profit during that challenging time. Alfalfa producers in Kentucky have also seen high prices and decent yields. While the drought of 2012 affected them, most still harvested an 80 % crop with extremely high prices and demand. The fact that alfalfa is a deep rooted plant, coupled with timely rains proved beneficial to this group.


Why Aren't Big Square Balers Used More In Kentucky?, Tom Keene Feb 2014

Why Aren't Big Square Balers Used More In Kentucky?, Tom Keene

Kentucky Alfalfa and Stored Forage Conference

The history of making hay dates back for centuries and centuries. When mankind began to grow crops and livestock rather than being nomadic, they had to have some type of forage to feed their livestock during the cold and winter months. Since that time there has been a slow and steady progression from harvesting material by hand to today’s modern hay making equipment that maximizes time, labor, fuel, etc. However some countries to this day still use the methods that are thousands of years old when it comes to hay making.


Alfalfa For Summer Grazing, Roy Burris, Garry D. Lacefield Feb 2014

Alfalfa For Summer Grazing, Roy Burris, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is most commonly used as a hay crop in the United States. However, with proper management, it can be utilized as a grazing crop with very good results. Liveweight gains per acre are quite high for grazing beef cattle with total season grains of 500 to 800 pounds per acre being reasonable. The authors realized 732 lb/acre of gains on 16 acres of alfalfa in 1991, with beef steers at Princeton.


Lessons Learned In Australia--Uk Forages Study Tour, Traci Missun, S. Ray Smith, Garry D. Lacefield Feb 2014

Lessons Learned In Australia--Uk Forages Study Tour, Traci Missun, S. Ray Smith, Garry D. Lacefield

Kentucky Alfalfa and Stored Forage Conference

In September 2013, twenty Kentuckians traveled to Australia to tour farms and attend the International Grasslands Congress. The group included ten county agents, five farmers, four UK faculty/staff and a teacher. This study tour allowed participants to gain a new perspective of agriculture and how Australian farmers deal with adversity. Farmers there face many challenges each year with change in precipitation, ranging from severe drought to flooding. These challenges have forced them to incorporate different methods to be successful, including intensive grazing, use of overhead and drip irrigation for pasture and hay production, and fallow farming.


Alfalfa Baleage/Silage Preservatives: Do They Work? Are They Economical?, S. Ray Smith Feb 2014

Alfalfa Baleage/Silage Preservatives: Do They Work? Are They Economical?, S. Ray Smith

Kentucky Alfalfa and Stored Forage Conference

There are many variables with silage production including - type of silage operation (silo, bunk, tube, or wrapped bale), weather, packing or bale density, speed of covering. Therefore, no two silage crops are ever the same, which is why researchers are reluctant to give blanket statements regarding when and how to use silage inoculants. There has been a lot of good research though in recent years about the effect of silage inoculants under various management and conditions. What follows is an overview of this research and some general recommendations. Much of this overview was taken from a very good fact …


Role And Importance Of Alfalfa In Wku Teaching/Research/Farm Programs, Elmer Gray Feb 2014

Role And Importance Of Alfalfa In Wku Teaching/Research/Farm Programs, Elmer Gray

Kentucky Alfalfa and Stored Forage Conference

Alfalfa is the oldest and most widely grown forage legume in the world and in Kentucky, where approximately 250,000 acres are produced. It has gained this top position through producing forage suitable for most classes of livestock, by being drought tolerant, and by fixing atmosphere nitrogen.


Foreword And Recipients Of Kentucky Alfalfa Awards [2014], Garry D. Lacefield, Christi L. Forsythe Feb 2014

Foreword And Recipients Of Kentucky Alfalfa Awards [2014], Garry D. Lacefield, Christi L. Forsythe

Kentucky Alfalfa and Stored Forage Conference

No abstract provided.


Limitations And Benefits To Cultivating Tobacco, Edwin L. Ritchey, Gary K. Palmer Jan 2014

Limitations And Benefits To Cultivating Tobacco, Edwin L. Ritchey, Gary K. Palmer

Plant and Soil Sciences Research Report

Historically, between-row cultivation for weed control has been an integral part of tobacco production. In one season, a grower might perform five or more cultivations and several hand weeding operations for adequate weed control. Early herbicide chemistries would control some weeds, but not all, forcing the producer to cultivate and hand weed. The development of better herbicides improved the range of weeds controlled, sometimes to the point that cultivation for weed control was not warranted. Many producers are so accustomed to cultivating they have forgotten why cultivation was necessary. The decision to cultivate should largely be based on the presence …


Comparison Of Herbicide Systems For Dark Fire-Cured Tobacco, William A. Bailey, Tim Lax, Bobby Hill Jan 2014

Comparison Of Herbicide Systems For Dark Fire-Cured Tobacco, William A. Bailey, Tim Lax, Bobby Hill

Plant and Soil Sciences Research Report

Field experiments were conducted at Murray, KY in 2005, 2006, and 2007 to compare dark tobacco tolerance and weed control from various herbicide systems applied prior to transplanting. Herbicide treatments included sulfentrazone at 0.38 lb ai/A (12 oz/A Spartan 4F) applied pretransplant (PT), clomazone at 1 lb ai/A PT (2.67 pt/A Command 3ME), sulfentrazone at 0.38 lb ai/A plus clomazone at 1 lb ai/A PT, pendimethalin at 1.48 lb ai/A (3.6 pt/A Prowl 3.3EC) applied pretransplant incorporated (PTI), pendimethalin at 1.48 lb ai/A PTI followed by sulfentrazone at 0.38 lb ai/A PT, pebulate at 4 lb ai/A PTI (2.67 qt/A …


Impact Of Climate Change On Wheat Production In Kentucky, Kathleen Russell, Chad Lee, Rebecca L. Mcculley, David Van Sanford Jan 2014

Impact Of Climate Change On Wheat Production In Kentucky, Kathleen Russell, Chad Lee, Rebecca L. Mcculley, David Van Sanford

Plant and Soil Sciences Research Report

Summary:

  • From 2002 to 2012, Kentucky winter wheat ranged in value from $52 million to $209 million.
  • Climate change and variability have the potential to significantly impact this important economic enterprise within our state.
  • This report summarizes the current state of knowledge of the potential of climate change to impact wheat production in Kentucky and surrounding states.


Kentucky Geological Survey Landslide Inventory: From Design To Application, Matthew M. Crawford Jan 2014

Kentucky Geological Survey Landslide Inventory: From Design To Application, Matthew M. Crawford

Information Circular--KGS

The Kentucky Geological Survey is compiling a landslide inventory database to better document the distribution and geologic context of Kentucky’s landslides. The database provides users with easy access to landslide information, raises awareness of landslide causes, and will help prevent property damage or injury. The database was used to create an online landslide information map, which provides online access to landslide data and gives users the ability to customize the map using other data layers pertinent to landslides. The database design is based on common attributes collected by other states with active inventories and landslide hazard programs, as well as …


Holocene Sedimentary Responses To Growth Faulting In A Back-Barrier Setting: East Matagorda Peninsula, Texas, Phillip Wolfe Jan 2014

Holocene Sedimentary Responses To Growth Faulting In A Back-Barrier Setting: East Matagorda Peninsula, Texas, Phillip Wolfe

Theses and Dissertations--Earth and Environmental Sciences

The structural framework of the northern Gulf of Mexico coastal zone is characterized by numerous growth fault systems. Neotectonic processes in coastal marshes in this region have been shown to be important drivers of relative sea-level rise as well as having significant influence on marsh accretion processes. One active growth fault has been identified at East Matagorda Peninsula, Texas. To characterize the Holocene behavior of this fault and the consequent sedimentary responses, a suite of fallout radionuclides (7Be, 137Cs, 210Pb) and radiocarbon, supplemented by sediment physical property data have been used to determine sediment mixing depths, …


Application Of The Kalman Filter On Full Tensor Gravity Gradiometry Data Around The Vinton Salt Dome, Louisiana, Mahnaz Sepehrmanesh Jan 2014

Application Of The Kalman Filter On Full Tensor Gravity Gradiometry Data Around The Vinton Salt Dome, Louisiana, Mahnaz Sepehrmanesh

Theses and Dissertations--Earth and Environmental Sciences

Full tensor gravity (FTG) data are known for their high resolution but also for higher noise in its components due to the dynamic nature of the platform used for data acquisition. Although a review of the literature suggests steady increase in the success of gravity gradiometry, we still cannot take advantage of the full potential of the method, mostly because of the noise with the same amplitude and wavenumber characteristics as the signal that affects these data. Smoothing from common low pass filters removes small wavelength features and makes it difficult to detect structural features and other density variations of …


Paleoseismic And Structural Characterization Of The Hines Creek Fault: Denali National Park And Preserve, Alaska, Sara E. Federschmidt Jan 2014

Paleoseismic And Structural Characterization Of The Hines Creek Fault: Denali National Park And Preserve, Alaska, Sara E. Federschmidt

Theses and Dissertations--Earth and Environmental Sciences

The Hines Creek fault (HCF) is a Holocene-active fault in central Alaska. Its trace has been mapped several times, but data on the history of fault displacement is scarce. As a major crustal-scale geologic boundary with uncertain Quaternary tectonic activity, it is a priority for more to be known about the activity of this fault to better understand the hazards it presents to the Denali National Park and Preserve and Alaskan infrastructure. This study characterizes the late Quaternary activity of the HCF through surficial geologic mapping and paleoseismic investigations. Mapping revealed a very steep (~84°-88° apparent dip), north dipping fault …


Age Of The Walden Creek Group, Western Blue Ridge Province: Resolving A Decades-Old Controversy Via Detrital Mineral Geochronology And Sedimentary Provenance Analysis, Evan A. Kelly Jan 2014

Age Of The Walden Creek Group, Western Blue Ridge Province: Resolving A Decades-Old Controversy Via Detrital Mineral Geochronology And Sedimentary Provenance Analysis, Evan A. Kelly

Theses and Dissertations--Earth and Environmental Sciences

Originally mapped as Precambrian and uppermost Ocoee Supergroup (OS), recent discoveries of Paleozoic microfossils have placed the Walden Creek Group (WCG), eastern Tennessee, into a younger depositional framework (Silurian or younger). In this study, monazite geochronology using SIMs, detrital zircon U-Pb geochronology determined by LA-ICP-MS, feldspar compositions determined by microprobe, zircon-tourmaline-rutile (ZTR) indices, and framework mineral modes were used to characterize provenance of sandstones of the WCG. Monazite ages cluster at 450 and 1050 Ma. All Ordovician ages are from grains that, in BSE images, have inclusion-rich microtextures interpreted as diagenetic and/or metamorphic, thus requiring that the WCG was deposited …