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Greener Pastures 2 - Nitrogen For Intensively Grazed Dairy Pastures, Martin Staines, Richard Morris, Tess Casson, Mike Bolland, Bill Russell, Ian Guthridge, John Lucey, Don Bennett Feb 2011

Greener Pastures 2 - Nitrogen For Intensively Grazed Dairy Pastures, Martin Staines, Richard Morris, Tess Casson, Mike Bolland, Bill Russell, Ian Guthridge, John Lucey, Don Bennett

Bulletins 4000 -

We undertook three main studies during the Greener Pastures project:

1. From mid 2005 to late 2008, a farming systems study was undertaken with five rates of nitrogen fertiliser as the main treatment. This study will be referred to as the ‘nitrogen response farmlets’.

2. From 2006 to 2008 a series of smaller ‘supporting’ studies were completed to investigate how grazing management influences the pasture production gains from nitrogen fertiliser. This will be referred to as the ‘nitrogen by growth-stage study’.

3. From early 2009 to early 2010, a farming systems study was undertaken to investigate the potential to increase …


Extended Grazing And Reduced Stored Feed, Edward N. Ballard Jan 2011

Extended Grazing And Reduced Stored Feed, 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. Typically the cost of supplying nutrients to ruminant livestock is much greater using harvested feedstuffs as opposed to grazing pastures or crop residues. The primary function of a grassland farm is to convert solar energy to marketable livestock products in the most efficient manner. The fewer steps between the animal product and …


Grazing Non-Traditional Forages, Jeff Mccutcheon Jan 2011

Grazing Non-Traditional Forages, Jeff Mccutcheon

Kentucky Grazing Conference

In the Heart of America region we are blessed with perennial cool-season grasses and legumes as the bulk of our forage production. Efficiently taking advantage of that perennial production is the focus of most grazing operations. Occasionally there are times when the production from our cool- season grass and legume pasture is not sufficient. In Ohio, that is late summer and late fall through winter till early spring. Nontraditional forages could be used when cool season forages are not producing. Non-traditional forages can provide a large volume, of high-quality feed during specific times of the year.


Grazing Goats And Cattle And Other Co-Species Grazing, Jason Tower Jan 2011

Grazing Goats And Cattle And Other Co-Species Grazing, Jason Tower

Kentucky Grazing Conference

Multispecies, co-species, mixed species grazing, it does not really matter what it is called they all revolve around the same premise; grazing more than one species of livestock on a given land area to improve resource use efficiencies.


Integrating Weed Management Practices To Enhance Productivity Of Grazed Pastures, Jonathan D. Green, Joshua Allen Tolson Jan 2011

Integrating Weed Management Practices To Enhance Productivity Of Grazed Pastures, Jonathan D. Green, Joshua Allen Tolson

Kentucky Grazing Conference

As animal grazing has intensified within Kentucky and the surrounding region problematic weeds such as tall ironweed, spiny amaranth, horsenettle, buttercup, common cocklebur, and thistles have been increasing. These weeds become prominent in pastures because they have spines, thorns, or are unpalatable to animals. Animals selectively graze and avoid these weedy plants and with intensive grazing practices their populations are allowed to increase. Livestock producers are seeking ways to increase pasture productivity by minimizing the impact of these and other weeds on grazed lands.


Mob Grazing, High Density Grazing, Management-Intensive Grazing: What's The Difference?, Mark Kennedy Jan 2011

Mob Grazing, High Density Grazing, Management-Intensive Grazing: What's The Difference?, Mark Kennedy

Kentucky Grazing Conference

Before we can answer that question we need to review some basic fundamentals of successful grazing management. Four goals of any sustainable grazing management strategy should be: 1) Meet the nutritional needs of livestock from standing pasture as many days as possible; 2) Optimize pasture yield, quality and persistence; 3) Maintain or enhance the natural resource base; 4) Integrate the appropriate technology and knowledge into a practical and profitable system that fits your available resources and meets your objectives. We will use these goals to compare and contrast these 2 grazing management techniques. Both techniques should be considered tools in …


Organic Dairying: Role Of Grazing, Jake Schmitz Jan 2011

Organic Dairying: Role Of Grazing, Jake Schmitz

Kentucky Grazing Conference

Certified organic and many conventional dairy farmers are using grazing techniques for a number of reasons, including building better soil, reducing feed costs, improving milk quality, and enhancing herd health. Additionally, certified organic farmers must utilize their pastures because the United States Department of Agriculture’s (USDA) organic rule requires organic cows to graze. Both the farmer and the USDA are working hard to ensure that “organic dairy” is synonymous with “grazing cows,” because the organic consumer vehemently demands dairy products from pasture-grazed livestock.


Impact Of The Endophyte On Animal Production, Glen Aiken Jan 2011

Impact Of The Endophyte On Animal Production, Glen Aiken

Kentucky Grazing Conference

Tall fescue is productive and well adapted to the soils and climate in a region commonly referred to as the “fescue belt”, which overlays the transition zone between the temperate northeast and subtropical southeast. Persistence of the grass under low input management is attributed to a fungal endophyte that infects most fescue plants and produces alkaloids that impart tolerance to heat, drought, and grazing stresses. Unfortunately, the endophyte also produces ergot alkaloids that can induce toxicosis. Signs of “fescue toxicosis” are elevated body temperature and respiration rate, retention of winter hair coats through the summer months, hormonal imbalances, and reduction …


How Much Pasture Do I Have And How Long Will It Feed My Cows?, S. Ray Smith Jan 2011

How Much Pasture Do I Have And How Long Will It Feed My Cows?, S. Ray Smith

Kentucky Grazing Conference

A very common question asked by cattlemen is, “How much pasture do I have and how long will it feed my cows.” The purpose of this paper is to provide some guidelines and tools for answering this question. In pasture systems, determining the amount of pasture is much harder than in grain-based feeding systems because feed may be allocated for more than one day and feed quantity and quality is influenced by weather, fertility, stand density, and season. In addition, not all the available forage is consumed and the plants continue to grow after they are grazed. Variation in quality …


From Confinement To Grazing, Bill Payne Jan 2011

From Confinement To Grazing, Bill Payne

Kentucky Grazing Conference

A Tale of Two Businesses:

I would like share an account of a transition from a conventional dairy operation to our current Management Intensive Grazing (MIG) enterprise. In 1974, I joined my father who had been dairying on a 265 acre farm in Lincoln County, Kentucky for twenty five years. We fed our registered Holsteins corn silage and alfalfa haylage and purchased a manufactured feed. Our herd of 70 Holsteins spent most of their time on concrete. We did make an effort to allow access to an exercise lot when weather permitted. However, during most of the 1990’s we spent …


Foreword And Conference Information [2011], Garry D. Lacefield, Christi L. Forsythe Jan 2011

Foreword And Conference Information [2011], Garry D. Lacefield, Christi L. Forsythe

Kentucky Grazing Conference

No abstract provided.


110 Years Of Avipoxvirus In The Galapagos Islands, Patricia Parker, Elizabeth Buckles, Heather Farrington, Kenneth Petren, Noah Whiteman, Robert Ricklefs, Jennifer Bollmer, Gustavo Jiménez-Uzcátegui Jan 2011

110 Years Of Avipoxvirus In The Galapagos Islands, Patricia Parker, Elizabeth Buckles, Heather Farrington, Kenneth Petren, Noah Whiteman, Robert Ricklefs, Jennifer Bollmer, Gustavo Jiménez-Uzcátegui

Biology Department Faculty Works

The role of disease in regulating populations is controversial, partly owing to the absence of good disease records in historic wildlife populations. We examined birds collected in the Galapagos Islands between 1891 and 1906 that are currently held at the California Academy of Sciences and the Zoologisches Staatssammlung Muenchen, including 3973 specimens representing species from two well-studied families of endemic passerine birds: finches and mockingbirds. Beginning with samples collected in 1899, we observed cutaneous lesions consistent with Avipoxvirus on 226 (6.3%) specimens. Histopathology and viral genotyping of 59 candidate tissue samples from six islands showed that 21 (35.6%) were positive …


Reproduction And Genetic Detection Of Veligers In Changing Dreissena Populations In The Great Lakes, Jeffrey L. Ram, Aos S. Karim, Payel Acharya, Pranav Jagtap, Sonal Purohit, Donna R. Kashian Jan 2011

Reproduction And Genetic Detection Of Veligers In Changing Dreissena Populations In The Great Lakes, Jeffrey L. Ram, Aos S. Karim, Payel Acharya, Pranav Jagtap, Sonal Purohit, Donna R. Kashian

Environmental Science and Geology Faculty Research Publications

Dreissenid bivalves, Dreissena polymorpha (zebra mussel) and Dreissena bugensis (quagga mussel) are biofouling species that invaded the Great Lakes region of North America from source populations in Europe in the 1980s. Initially, D. polymorpha spread faster and farther; however, D. bugensis have recently displaced D. polymorpha in many areas of the Great Lakes and was the first to be found west of the Continental Divide. Early detection of dreissenids is important in anticipating and preventing potentially high economic impacts. To study population dynamics and to enhance detection methods, we assessed “spawnability” using a serotonin bioassay and developed a new, sensitive, …


Soil Organic Matter Dynamics In Bioenergy Cropping Systems, Jane Achando Khatenje Jan 2011

Soil Organic Matter Dynamics In Bioenergy Cropping Systems, Jane Achando Khatenje

Student Theses and Dissertations

Ethanol and other advanced biofuels from cellulosic biomass, plant stalks, trunks, stems, and leaves are renewable alternatives expected to significantly produce improved or expanded renewable energy sources to meet the current energy demand. Therefore, we need to better understand the production of renewable energy sources needs. The long term combined effects of tillage, cropping systems and nutrient sources fertilization on active and slow fractions of soil organic matter dynamics need to be realized. The objectives of this research are to: 1) determine the effects of different nutrient sources on soil organic matter dynamics and 2) determine the effects of bioenergy …


Temperature Increase Effects On Sagebrush Ecosystem Forbs: Exprimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb Jan 2011

Temperature Increase Effects On Sagebrush Ecosystem Forbs: Exprimental Evidence And Range Manager Perspectives, Hilary Louise Whitcomb

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Essentials Of Geographic Information Systems, Jonathan E. Campbell, Michael Shin Jan 2011

Essentials Of Geographic Information Systems, Jonathan E. Campbell, Michael Shin

Textbooks

This is the required textbook for ENVR 370 at Liberty University.


A Picture Is Worth 972 Words: The Old, Red Barn, Chris Laingen Jan 2011

A Picture Is Worth 972 Words: The Old, Red Barn, Chris Laingen

Faculty Research and Creative Activity

No abstract provided.


Active Pharmaceutical Ingredients And Aquatic Organisms, Christian G. Daughton, Bryan W. Brooks Jan 2011

Active Pharmaceutical Ingredients And Aquatic Organisms, Christian G. Daughton, Bryan W. Brooks

United States Environmental Protection Agency: Publications

The presence of active pharmaceuticals ingredients (APIs) in aquatic systems has led in recent years to a burgeoning literature examining environmental occurrence, fate, effects, risk assessment, and treatability of these compounds. The vast preponderance of studies aimed at identifying and quantifying contaminant residues in aquatic tissues have involved the conventional and legacy pollutants. Comparatively few studies have been targeted at APIs, primarily those that are lipophilic. Although APIs have received much attention as "emerging" contaminants of concern, it is important to recognize that traditional approaches to understand and predict exposure and effects of other environmental organic contaminant classes mayor may …


Ecology And Biogeography Of The Piedmont Blue Burrower (Cambarus [Depressicambarus] Harti), Troy Keller Jan 2011

Ecology And Biogeography Of The Piedmont Blue Burrower (Cambarus [Depressicambarus] Harti), Troy Keller

Faculty Bibliography

No abstract provided.


Profiles In Science For Science Librarians: "What Lives Where, And Why": Alfred Russel Wallace, And The Field Of Biogeography, Charles H. Smith Jan 2011

Profiles In Science For Science Librarians: "What Lives Where, And Why": Alfred Russel Wallace, And The Field Of Biogeography, Charles H. Smith

DLPS Faculty Publications

Biogeography, the study of animal and plant distribution, has a history extending back to at least the eighteenth century. But it was not until the work of Charles Darwin and Alfred Russel Wallace in the mid-nineteenth century that it really came into its own as a science. Darwin’s importance notwithstanding, it was really Wallace who put the field on the map, and many of today’s research threads can be traced back to his influence. This article provides a summary review of Wallace’s life and work and biogeography as a field of study, including Wallace’s role in its development.


Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf Jan 2011

Farmer Perceptions Of Sustainable Agriculture Practices And Drought Risk Reduction In Nebraska, Usa, Cody L. Knutson, Tonya Haigh, Michael J. Hayes, Melissa Widhalm, J. Nothwehr, M. Kleinschmidt, L. Graf

National Drought Mitigation Center: Faculty Publications

Social factors, such as farming methods, have an impact on farm vulnerability to drought, but have received little research or policy attention. Some researchers and advocates have argued that sustainable agriculture systems are less vulnerable to climate risk than conventional systems because sustainable agriculture requires producers to have skills promoting adaptability. In this paper, we investigate producers’ perceptions on the use of sustainable agriculture in reducing drought risk, and what they believe would help them better adapt to drought. We surveyed and interviewed farmer members of two sustainable agriculture organizations in Nebraska, USA, during a multi-year drought period from 1999 …


Estimating Age From Recapture Data: Integrating Incremental Growth Measures With Ancillary Data To Infer Age-At-Length, Mitchell J. Eaton, William A. Link Jan 2011

Estimating Age From Recapture Data: Integrating Incremental Growth Measures With Ancillary Data To Infer Age-At-Length, Mitchell J. Eaton, William A. Link

United States Geological Survey: Staff Publications

Estimating the age of individuals in wild populations can be of fundamental importance for answering ecological questions, modeling population demographics, and managing exploited or threatened species. Significant effort has been devoted to determining age through the use of growth annuli, secondary physical characteristics related to age, and growth models. Many species, however, either do not exhibit physical characteristics useful for independent age validation or are too rare to justify sacrificing a large number of individuals to establish the relationship between size and age. Length-at-age models are well represented in the fisheries and other wildlife management literature. Many of these models …


Selected Approaches To Estimate Water-Budget Components Of The High Plains, 1940 Through 1949 And 2000 Through 2009, Jennifer S. Stanton, Sharon L. Qi, Derek W. Ryter, Sarah E. Falk, Natalie A. Houston, Steven M. Peterson, Stephen M. Westenbroek, Scott C. Christenson Jan 2011

Selected Approaches To Estimate Water-Budget Components Of The High Plains, 1940 Through 1949 And 2000 Through 2009, Jennifer S. Stanton, Sharon L. Qi, Derek W. Ryter, Sarah E. Falk, Natalie A. Houston, Steven M. Peterson, Stephen M. Westenbroek, Scott C. Christenson

United States Geological Survey: Water Reports and Publications

The High Plains aquifer, underlying almost 112 million acres in the central United States, is one of the largest aquifers in the Nation. It is the primary water supply for drinking water, irrigation, animal production, and industry in the region. Expansion of irrigated agriculture throughout the past 60 years has helped make the High Plains one of the most productive agricultural regions in the Nation. Extensive withdrawals of groundwater for irrigation have caused water-level declines in many parts of the aquifer and increased concerns about the long-term sustainability of the aquifer.

Quantification of water-budget components is a prerequisite for effective …


The Role Of Demographic Compensation Theory In Incidental Take Assessments For Endangered Species, Conor P. Mcgowan, Mark R. Ryan, Michael C. Runge, Joshua J. Millspaugh, Jean Fitts Cochrane Jan 2011

The Role Of Demographic Compensation Theory In Incidental Take Assessments For Endangered Species, Conor P. Mcgowan, Mark R. Ryan, Michael C. Runge, Joshua J. Millspaugh, Jean Fitts Cochrane

United States Geological Survey: Staff Publications

Many endangered species laws provide exceptions to legislated prohibitions through incidental take provisions as long as take is the result of unintended consequences of an otherwise legal activity. These allowances presumably invoke the theory of demographic compensation, commonly applied to harvested species, by allowing limited harm as long as the probability of the species’ survival or recovery is not reduced appreciably. Demographic compensation requires some density-dependent limits on survival or reproduction in a species’ annual cycle that can be alleviated through incidental take. Using a population model for piping plovers in the Great Plains, we found that when the population …


Selenium In Birds, Harry M. Ohlendorf, Gary H. Heinz Jan 2011

Selenium In Birds, Harry M. Ohlendorf, Gary H. Heinz

United States Geological Survey: Staff Publications

Selenium (Se) is a metalloid trace element that birds and other wildlife need in small amounts for good health. The main purpose of this chapter is to interpret tissue concentrations of Se. However, because food is the main source of Se accumulation for birds and other wildlife, and because dietary concentrations for effects on bird reproduction have been reported, we also provide interpretive information on Se in the diet.

Se deficiencies in domestic poultry and livestock occur in some parts of the world and must be corrected by additions of Se to the diet. However, the range of dietary concentrations …


History Of Wildlife Toxicology And The Interpretation Of Contaminant Concentrations In Tissues, Barnett A. Rattner, Anton M. Scheuhammer, John E. Ellott Jan 2011

History Of Wildlife Toxicology And The Interpretation Of Contaminant Concentrations In Tissues, Barnett A. Rattner, Anton M. Scheuhammer, John E. Ellott

United States Geological Survey: Staff Publications

The detection and interpretation of contaminants in tissues of wildlife belongs to the field of toxicology, a scientific discipline with a long, intriguing, and illustrious history (reviewed by Hayes 1991, Gallo 2001, Gilbert and Hayes 2006, Wax 2006). We review its history briefly, to provide a context for understanding the use of tissue residues in toxicology, and to explain how their use has developed over time. Because so much work has been conducted on mercury, and dioxins and polychlorinated biphenyls (PCBs), separate case histories are included that describe the evolution of the use of tissue concentrations to assess exposure and …


Droughtscape, Winter 2011, Kelly Smith Jan 2011

Droughtscape, Winter 2011, Kelly Smith

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Register for the U.S. Drought Monitor Forum

La Niña Brings Southeast, Southwest Drought

International Efforts

Drought Returns in 2010

Impacts Emerge “Before” Summer Drought in East

October-December Quarterly Impacts Summary

Climate Adaptation for Local Government

NDMC Elicits Missouri River Basin Recollections

Woudenberg Coordinates Educational Booklet


Greener Pastures 7 - A Fresh Look At Nutrient Losses From Intensively Managed Pastures, Don Bennett, Bill Russell, Martin Staines, Richard Morris, Mike Bolland, John Lucey Jan 2011

Greener Pastures 7 - A Fresh Look At Nutrient Losses From Intensively Managed Pastures, Don Bennett, Bill Russell, Martin Staines, Richard Morris, Mike Bolland, John Lucey

Bulletins 4000 -

Dairy farmers in Western Australia have a long history of being concerned for the environment in which they live and work, from early involvement with Landcare District Committees through to participating in the various programs run in DairyCatch.

They have planted trees, organised soil testing programs, carried out salinity surveys and, more recently, have signed up for effluent, nutrient and irrigation water management programs. Many of these programs produce benefits both on and off the farm—they can improve the farm environment, increase farm productivity and reduce nutrient losses to surface and ground water. The wider community has supported farmers with …


Landscapes And Soils Of The Lake Grace District, D N. Sawkins Jan 2011

Landscapes And Soils Of The Lake Grace District, D N. Sawkins

Bulletins 4000 -

The publication aims to provide readers with the principles underlying the formation of local landscapes and soils, and the ability to identify landscapes and their associated soils.


Growth Rate Biometric Quantification By X-Ray Microtomography On Larger Benthic Foraminifera: Three-Dimensional Measurements Push Nummulitids Into The Fourth Dimension, Antonino Briguglio, Brian Metscher, Johann Hohenegger Jan 2011

Growth Rate Biometric Quantification By X-Ray Microtomography On Larger Benthic Foraminifera: Three-Dimensional Measurements Push Nummulitids Into The Fourth Dimension, Antonino Briguglio, Brian Metscher, Johann Hohenegger

Turkish Journal of Earth Sciences

This work demonstrates the potential of three-dimensional biometric quantification using microtomography on larger benthic foraminifera. We compare traditional linear and area measures used for calculating three-dimensional characters with actual 3D measurements made from volume images obtained using X-ray microtomography (microCT). Two specimens of recent larger benthic foraminifera, i.e., Palaeonummulites venosus and Operculina ammonoides, were imaged with a high-resolution microCT scanner. This method enables three-dimensional imaging and calculation of measurements like 3D distances, surfaces and volumes. The quantitative high-resolution images enabled the extraction of the lumina from the proloculus to the last complete scanned chamber and of the canal system spreading …