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Geologic Mapping, Alluvial Stratigraphy, And Optically Stimulated Luminescence Dating Of The Kanab Creek Area, Southern Utah, Michelle Carlene Summa Dec 2009

Geologic Mapping, Alluvial Stratigraphy, And Optically Stimulated Luminescence Dating Of The Kanab Creek Area, Southern Utah, Michelle Carlene Summa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

At the turn of the century, Kanab Creek incised 30-meters into its alluvium, leaving behind fluvial terraces and thick basin fill sediments exposed along arroyo walls. Research objectives were to determine the timing and causes of past valley-filling and arroyo-cutting episodes along a 20 km-long reach of Kanab Creek in southern Utah. Fluvial deposits were mapped at the 1:12,000 scale and sediments were described and dated using Optically Stimulated Luminescence (OSL) and radiocarbon dating.

The Kanab Creek valley can be divided into a narrow, upper terraced reach and a broad lower basin fill reach near Kanab, Utah. The most prominent …


Salinity Inventory And Tolerance Screening In Utah Agriculture, Austin Mccoy Hawks Dec 2009

Salinity Inventory And Tolerance Screening In Utah Agriculture, Austin Mccoy Hawks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soil salinity, a yield-limiting condition, has plagued crop production for centuries by reducing crop productivity. Research has introduced methods for successfully managing soil salinity. This research discusses the adaptation of established management methods to create new soil salinity management techniques.

One adapted technique is an automated crop screening apparatus. A new design was created and successfully used in rapidly screening two strawberry cultivars to determine their tolerance to salinity. Screening crops and determining their tolerance to yield-limiting conditions are essential in managing soil salinity.

Another salinity management tool used in this research was electromagnetic induction (EMI). EMI was used to …


Health Impacts Of Traffic Related Air Pollution, Amit U. Raysoni, Wen-Wahi Li Dec 2009

Health Impacts Of Traffic Related Air Pollution, Amit U. Raysoni, Wen-Wahi Li

School of Earth, Environmental, & Marine Sciences Faculty Publications

Ambient air pollution can be a serious cause of concern for any community. Anthropogenic ambient air pollutants can emanate from industries, traffic, geological sources and domestic heating and cooking. However, studies have shown that traffic related air pollution can have far more detrimental health effects than non-combustion sources. These adverse health effects are most profound in sensitive populations like the elderly and young children. The World Health Organization (WHO) attributes more than 300 million deaths every year to ambient air pollution. The WHO’s Air Quality Guidelines (AQG) and the United States Environment Protection Agency’s (USEPA) National Ambient Air Quality Standards …


Block Modeling With Multiple Fault Network Geometries And A Linear Elastic Coupling Estimator In Spherical Coordinates, Brendan J. Meade, John P. Loveless Dec 2009

Block Modeling With Multiple Fault Network Geometries And A Linear Elastic Coupling Estimator In Spherical Coordinates, Brendan J. Meade, John P. Loveless

Geosciences: Faculty Publications

Geodetic observations of interseismic deformation provide constraints on the partitioning of fault slip across plate boundary zones, the spatial distribution of both elastic and inelastic strain accumulation, and the nature of the fault system evolution. Here we describe linear block theory, which decomposes surface velocity fields into four components: (1) plate rotations, (2) elastic deformation from faults with kinematically consistent slip rates, (3) elastic deformation from faults with spatially variable coupling, and (4) homogeneous intrablock strain. Elastic deformation rates are computed for each fault segment in a homogeneous elastic half-space using multiple optimal planar Cartesian coordinate systems to minimize areal …


Dinosaurian Faunas Of The Cedar Mountain Formation And La-Icp-Ms Detrital Zircon Ages For Three Stratigraphic Sections, Hirotsugu Mori Nov 2009

Dinosaurian Faunas Of The Cedar Mountain Formation And La-Icp-Ms Detrital Zircon Ages For Three Stratigraphic Sections, Hirotsugu Mori

Theses and Dissertations

The Cedar Mountain Formation contains the most diverse record of Early Cretaceous dinosaurs in the western hemisphere. However, analyses of its faunas have been hindered because 1) most taxa are based on incomplete/fragmentary materials or incomplete descriptions, 2) most sites and some horizons preserve few taxa, and 3) the stratigraphy and geochronology are poorly understood. To help resolve these stratigraphic and correlation problems U-Pb LA-ICP-MS detrital zircon ages were obtained at significant sites and horizons. These dates indicate all sites at or near the base of the formation are no older than 122 to 124 Ma, thus all basal stratigraphic …


Preparing Water Users In The Lower Rio Grande For Adjudication Through An Informative Workshop, Leslie R. Kryder Nov 2009

Preparing Water Users In The Lower Rio Grande For Adjudication Through An Informative Workshop, Leslie R. Kryder

Water Resources Professional Project Reports

The Lower Rio Grande basin in New Mexico is currently undergoing water right adjudication. The adjudication process is important to identify and quantify water uses throughout the Lower Rio Grande. It is intended to facilitate water rights administration by the Office of the State Engineer. Where water users do not understand the purpose and process, they may not participate effectively. Through conversations with irrigators and others familiar with the situation, I explore some of the water users perspectives regarding the adjudication. In general, the water users find the adjudication packets received from the Office of the State Engineer difficult to …


Accurate Inversion Of High-Resolution Snow Penetrometer Signals For Microstructural And Micromechanical Properties, Hans-Peter Marshall, Jerome B. Johnson Nov 2009

Accurate Inversion Of High-Resolution Snow Penetrometer Signals For Microstructural And Micromechanical Properties, Hans-Peter Marshall, Jerome B. Johnson

CGISS Publications and Presentations

Measurements of snow using a high-resolution micropenetrometer can be used to discriminate between different snow types; in lower-density snow the signal is sensitive to microstructure, and micromechanical properties can be estimated. Although a physics-based snow penetration theory was first developed almost a decade ago, since that time the majority of studies using snow micropenetrometers have focused on using direct hardness measurements in statistical relationships. We use Monte-Carlo simulations to rigorously test the existing physics-based snow micropenetration theories over a wide range of parameters. These tests revealed four major sources of error in the inversion, which are corrected in this analysis. …


Future Cascadia Megathrust Rupture Delineated By Episodic Tremor And Slip, James S. Chapman, Timothy I. Melbourne Nov 2009

Future Cascadia Megathrust Rupture Delineated By Episodic Tremor And Slip, James S. Chapman, Timothy I. Melbourne

Faculty Scholarship for the Cascadia Hazards Institute

A suite of 15 episodic tremor and slip events imaged between 1997 and 2008 along the northern Cascadia subduction zone suggests future coseismic rupture will extend to 25 km depth, or approximately 60 km inland of the Pacific coast, rather than stopping offshore at 15 km depth. An ETS-derived coupling profile accurately predicts GPS measured interseismic deformation of the overlying North American plate, as measured by approximately 50 continuous GPS stations across western Washington State. When extrapolated over the 550-year average recurrence interval of Cascadia megathrust events, the coupling model also replicates the pattern and amplitude of coseismic coastal subsidence …


A La-Icpms Sr Isotope And Trace Element Study Of Plagioclase And Clinopyroxene Of The Higganum Dike, Connecticut: Determining The Magma Source Of The Central Atlantic Magmatic Province, Caprise Steadman Harper Nov 2009

A La-Icpms Sr Isotope And Trace Element Study Of Plagioclase And Clinopyroxene Of The Higganum Dike, Connecticut: Determining The Magma Source Of The Central Atlantic Magmatic Province, Caprise Steadman Harper

Theses and Dissertations

The Higganum dike of Connecticut is one of the earliest basaltic dikes of the Central Atlantic Magmatic province and is geochemically representative of the widespread low-Ti basaltic lavas (~1 wt % TiO2) that make up the majority of the province in North America. Liquid compositions calculated from Cr-rich clinopyroxene cores from the Higganum dike are significantly more primitive than the bulk rock with average Mg# s of 0.63 compared to the Higganum dike which has Mg #'s ~ 0.55. However, the negative Nb and positive Pb anomalies that are seen in trace element patterns of the low-Ti group are also …


White River Forum Ii: Second Annual Meeting Of The White River Forum, John Havel, Kenneth Steele Nov 2009

White River Forum Ii: Second Annual Meeting Of The White River Forum, John Havel, Kenneth Steele

Arkansas Water Resources Center Technical Reports

This second annual meeting of the White River Forum is proof of widespread interest in the water quality of the Upper White River watershed. The participation of numerous elected officials, state and federal agencies, universities, businesses, and local citizens indicates that interest in understanding policy issues crosses political boundaries and occupations.


Effects Of Composted And Raw Manure And Ammonium Sulfate Applications On The Chemical Properties Of The Soils At Chorro Creek Ranch, San Luis Obispo, Ca., Renee Nall,, Craig Stubler, Christopher Appel, Tanner Campbell, Jose Gomez, Nathan Lurie, Russell Morgan, J. J. Scurich Nov 2009

Effects Of Composted And Raw Manure And Ammonium Sulfate Applications On The Chemical Properties Of The Soils At Chorro Creek Ranch, San Luis Obispo, Ca., Renee Nall,, Craig Stubler, Christopher Appel, Tanner Campbell, Jose Gomez, Nathan Lurie, Russell Morgan, J. J. Scurich

Earth and Soil Sciences

The majority of agricultural systems, especially large-scale, require inputs of nutrients. In addition, many large scale dairies produce vast quantities of waste that can be potentially recycled as nutrients. This study was conducted to determine the differences in properties of soils amended with manure, compost, and fertilizer, and to assess implications of using animal waste products for forage crop fertilization. Forage crops, wheat, barley, and oat mix have been grown on the Chorro Creek Ranch part of Cal Poly farmland, for 15 years. Ammonium sulfate fertilizer has been applied at a rate of 200 lbs/acre/year for the past 4 years. …


The Upper Lithostratigraphic Unit Of Andrill And-2a Core (Southern Mcmurdo Sound, Antarctica): Local Pleistocene Volcanic Sources, Paleoenvironmental Implications And Subsidence In The Southern Victoria Land Basin, Paola Del Carlo, Kurt Panter, Kari Bassett, Laura Bracciali, Gianfranco Di Vincenzo, Sergio Rocchi Nov 2009

The Upper Lithostratigraphic Unit Of Andrill And-2a Core (Southern Mcmurdo Sound, Antarctica): Local Pleistocene Volcanic Sources, Paleoenvironmental Implications And Subsidence In The Southern Victoria Land Basin, Paola Del Carlo, Kurt Panter, Kari Bassett, Laura Bracciali, Gianfranco Di Vincenzo, Sergio Rocchi

ANDRILL Research and Publications

We report results from the study of the uppermost 37 m of the Southern McMurdo Sound (SMS) AND-2A drill core, corresponding to the lithostratigraphic unit 1 (LSU 1), the most volcanogenic unit within the core. We present data on the age, composition, volcanological and depositional features of the volcanic sedimentary and tephra deposits of LSU 1 and discuss their source, mechanisms of emplacement and environment of deposition.

Sedimentary features and compositional data indicate shallow water sedimentation for the whole of LSU 1. Most of LSU 1 deposits are a mixture of near primary volcanic material with minor exotic clasts derived …


Stability Of The Rotation Axis In High‐Resolution Mantle Circulation Models: Weak Polar Wander Despite Strong Core Heating, K. Schaber, H. -P. Bunge, B. S. A. Schuberth, Rocco Malservisi, A. Horbach Nov 2009

Stability Of The Rotation Axis In High‐Resolution Mantle Circulation Models: Weak Polar Wander Despite Strong Core Heating, K. Schaber, H. -P. Bunge, B. S. A. Schuberth, Rocco Malservisi, A. Horbach

School of Geosciences Faculty and Staff Publications

Growing evidence points to a substantial heat flow across the core‐mantle boundary (CMB), but the rotational stability of strongly bottom heated mantle flow with prominent upwelling plumes is poorly known. Here we calculate polar motion for the past 100 Myr induced in a new class of isochemical high‐resolution mantle circulation models (MCMs) with Earth‐like convective vigor and up to 12 TW core heat flux. Our MCMs include internal heating and a simple three‐layer viscosity profile associated with the lithosphere (1023 Pa s) and the upper (1021 Pa s) and the lower mantle (1023 Pa s), separated at 100 and 650 …


Implementation Of Sustainable Management Practices At Two California Central Coast Vineyards And Their Effects On Soil Fertility, Dawn M. Stimson Nov 2009

Implementation Of Sustainable Management Practices At Two California Central Coast Vineyards And Their Effects On Soil Fertility, Dawn M. Stimson

Master's Theses

Implementation of Sustainable Management Practices at Two California Central Coast Vineyards and Their Effects on Soil Fertility

Dawn Michelle Stimson

“Sustainable agriculture” has gained increased popularity in recent years. This study was conducted to determine the effects of sustainable management practices on soil fertility at two California Central Coast vineyards. The effects of cover crops (Erosion Control Mix - blando brome [Bromus hordeaceus], hykon rose clover [Trifolium hirtum All.], and zorro annual fescue [Vulpia mourns]), green waste compost (Forest Blend), and reduced tillage on soil fertility were investigated in San Luis Obispo, California on a clay and sandy loam soil. …


Plains Co2 Reduction (Pcor) Partnership Atlas, Wesley D. Peck, Katherine K. Anagnost, Barry W. Botnen, Lisa S. Botnen, Daniel J. Daly, Charles D. Gorecki, Megan M. Grove, John A. Harju, Melanie D. Jensen, Michael L. Jones, Steven A. Smith, James A. Sorensen, Edward N. Steadman, Stephanie L. Wolfe, Andrea T. Mcnemar, John T. Litynski, Sean I. Plasynski Nov 2009

Plains Co2 Reduction (Pcor) Partnership Atlas, Wesley D. Peck, Katherine K. Anagnost, Barry W. Botnen, Lisa S. Botnen, Daniel J. Daly, Charles D. Gorecki, Megan M. Grove, John A. Harju, Melanie D. Jensen, Michael L. Jones, Steven A. Smith, James A. Sorensen, Edward N. Steadman, Stephanie L. Wolfe, Andrea T. Mcnemar, John T. Litynski, Sean I. Plasynski

EERC Maps and Infographics

The Plains CO2 Reduction (PCOR) atlas, 3rd edition, introduces global climate change and provides a regional profile of CO2 sources and potential sinks across the PCOR Partnership region. Carbon storage offers a promising set of technologies through which CO2 can be stored for long periods of time.


Probabilistic Tsunami Hazard Assessment At Seaside, Oregon, For Near- And Far-Field Seismic Sources, Frank González, Eric L. Geist, Bruce Jaffe, Utku Kânoğlu, Harold O. Mofjeld, Costas Synolakis, Vasily V. Titov, Diego Rodriguez Arcas, Douglas Bellomo, David Carlton, Thomas Horning, Jeff Johnson, Jean Newman, Thomas Parsons, Robert Peters, Curt D. Peterson, George Priest, Angie Venturato, Joseph Weber, Florence L. Wong, Ahmet Yalçıner Nov 2009

Probabilistic Tsunami Hazard Assessment At Seaside, Oregon, For Near- And Far-Field Seismic Sources, Frank González, Eric L. Geist, Bruce Jaffe, Utku Kânoğlu, Harold O. Mofjeld, Costas Synolakis, Vasily V. Titov, Diego Rodriguez Arcas, Douglas Bellomo, David Carlton, Thomas Horning, Jeff Johnson, Jean Newman, Thomas Parsons, Robert Peters, Curt D. Peterson, George Priest, Angie Venturato, Joseph Weber, Florence L. Wong, Ahmet Yalçıner

Geology Faculty Publications and Presentations

The first probabilistic tsunami flooding maps have been developed. The methodology, called probabilistic tsunami hazard assessment (PTHA), integrates tsunami inundation modeling with methods of probabilistic seismic hazard assessment (PSHA). Application of the methodology to Seaside, Oregon, has yielded estimates of the spatial distribution of 100- and 500-year maximum tsunami amplitudes, i.e., amplitudes with 1% and 0.2% annual probability of exceedance. The 100-year tsunami is generated most frequently by far-field sources in the Alaska-Aleutian Subduction Zone and is characterized by maximum amplitudes that do not exceed 4 m, with an inland extent of less than 500 m. In contrast, the 500-year …


Microbial-Induced Heterogeneity In The Acoustic Properties Of Porous Media, Caroline A. Davis, Laura J. Pyrak-Nolte, Estella A. Atekwana, D. Dale, Werkema, Marisa E. Haugen Nov 2009

Microbial-Induced Heterogeneity In The Acoustic Properties Of Porous Media, Caroline A. Davis, Laura J. Pyrak-Nolte, Estella A. Atekwana, D. Dale, Werkema, Marisa E. Haugen

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

It is not known how biofilms affect seismic wave propagation in porous media. Such knowledge is critical for assessing the utility of seismic techniques for imaging biofilm development and their effects in field settings. Acoustic wave data were acquired over a two-dimensional region of a microbial-stimulated sand column and an unstimulated sand column. The acoustic signals from the unstimulated column were relatively uniform over the 2D scan region. The data from the microbial-stimulated column exhibited a high degree of spatial heterogeneity in the acoustic wave amplitude, with some regions exhibiting significant increases in attenuation while others exhibited decreases. Environmental scanning …


From Decades To Epochs: Spanning The Gap Between Geodesy And Structural Geology Of Active Mountain Belts, Richard W. Allmendinger, John P. Loveless, Matthew E. Pritchard, Brendan Meade Nov 2009

From Decades To Epochs: Spanning The Gap Between Geodesy And Structural Geology Of Active Mountain Belts, Richard W. Allmendinger, John P. Loveless, Matthew E. Pritchard, Brendan Meade

Geosciences: Faculty Publications

Geodetic data from the Global Navigation Satellite System (GNSS), and from satellite interferometric radar (InSAR) are revolutionizing how we look at instantaneous tectonic deformation, but the significance for long-term finite strain in orogenic belts is less clear. We review two different ways of analyzing geodetic data: velocity gradient fields from which one can extract strain, dilatation, and rotation rate, and elastic block modeling, which assumes that deformation is not continuous but occurs primarily on networks of interconnected faults separating quasi-rigid blocks. These methods are complementary: velocity gradients are purely kinematic and yield information about regional deformation; the calculation does not …


Coupled Collaborative In-Class Activities And Individual Follow-Up Homework Promote Interactive Engagement And Improve Student Learning Outcomes In A College-Level Environmental Geology Course, Leilani Arthurs, Alexis Templeton Nov 2009

Coupled Collaborative In-Class Activities And Individual Follow-Up Homework Promote Interactive Engagement And Improve Student Learning Outcomes In A College-Level Environmental Geology Course, Leilani Arthurs, Alexis Templeton

Department of Earth and Atmospheric Sciences: Faculty Publications

Interactive engagement pedagogies that emerge from a constructivist model of teaching and learning are often a challenge to implement in larger classes for a number of reasons including the physical layout of the classroom (e.g. fixed chairs in an amphitheater-style room), the logistics of organizing a large number of students into small peer-learning groups, the ability of a single instructor to personally interact with each of many small groups, and the design of small group activities that are engaging and facilitate student learning. For a large introductory-level Environmental Geology college course, 5 coupled collaborative class-long in-class activities and individual follow-up …


Seismic And Geodetic Constraints On Cascadia Slow Slip, Timothy I. Melbourne, Aaron G. Wech, Kenneth C. Creager Oct 2009

Seismic And Geodetic Constraints On Cascadia Slow Slip, Timothy I. Melbourne, Aaron G. Wech, Kenneth C. Creager

Faculty Scholarship for the Cascadia Hazards Institute

Automatically detected and located tremor epicenters from episodic tremor and slip (ETS) episodes in northern Cascadia provide a high-resolution map of Washington’s slow slip region. Thousands of epicenters from the past four ETS events from 2004 to 2008 provide detailed map-view constraints that correlate with geodetic estimates of the simultaneous slow slip. Each of these ETS events exhibits remarkable similarity in the timing and geographic distribution of tremor density and geodetically inferred slip. Analysis of the latest 15-month inter-ETS period also reveals ageodetic tremor activity similar both in duration and extent to ETS tremor. Epicenters from both ETS and inter- …


Fold And Thrust Partitioning In A Contracting Fold Belt: Insights From The 1931 Mach Earthquake In Baluchistan, Walter Szeliga, Roger Bilham, Daniel Schelling, Din Mohamed Kakar, Sarosh Lodi Oct 2009

Fold And Thrust Partitioning In A Contracting Fold Belt: Insights From The 1931 Mach Earthquake In Baluchistan, Walter Szeliga, Roger Bilham, Daniel Schelling, Din Mohamed Kakar, Sarosh Lodi

Faculty Scholarship for the Cascadia Hazards Institute

Surface deformation associated with the 27 August 1931 earthquake near Mach in Baluchistan is quantified from spirit-leveling data and from detailed structural sections of the region interpreted from seismic reflection data constrained by numerous well logs. Mean slip on the west dipping Dezghat/Bannh fault system amounted to 1.2 m on a 42 km x 72 km thrust plane with slip locally attaining 3.2 m up dip of an inferred locking line at approximately 9 km depth. Slip also occurred at depths below the interseismic locking line. In contrast, negligible slip occurred in the 4 km near the interseismic locking line. …


Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood Oct 2009

Similarity Of Nutrient Uptake And Root Dimensions Of Engelmann Spruce And Subalpine Fir At Two Contrasting Sites In Colorado, Melissa S. Lucash, Ruth D. Yanai, Karis J. Mcfarlane, Sarah E. Kulpa, Dustin M. Wood

Environmental Science and Management Faculty Publications and Presentations

Nutrient uptake capacity is an important parameter in modeling nutrient uptake by plants. Researchers commonly assume that uptake capacity measured for a species can be used across sites. We tested this assumption by measuring the nutrient uptake capacity of intact roots of Engelmann spruce (Picea engelmanni Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) at Loch Vale Watershed and Fraser Experimental Forest in the Rocky Mountains of central Colorado. Roots still attached to the tree were exposed to one of three concentrations of nutrient solutions for time periods ranging from 1 to 96h, and solutions were analyzed for ammonium, …


Photo Highlights Of The 10th Kentucky Grazing Conference, Kentucky Grazing Conference Oct 2009

Photo Highlights Of The 10th Kentucky Grazing Conference, Kentucky Grazing Conference

Kentucky Grazing Conference

No abstract provided.


Forage Spokesman Information, Tom Flowers, Vince Rawe, Caldwell Willig Oct 2009

Forage Spokesman Information, Tom Flowers, Vince Rawe, Caldwell Willig

Kentucky Grazing Conference

No abstract provided.


Animal Welfare--Animal Rights: Role Of Grazing, Roy Burris Oct 2009

Animal Welfare--Animal Rights: Role Of Grazing, Roy Burris

Kentucky Grazing Conference

The care and handling of farm animals has drawn a lot of media attention lately. Some well-publicized events have given our industry the proverbial black-eye and led to a chain of events that has left livestock producers feeling very vulnerable to negative attacks. Although these events have been very isolated, they have had some very farreaching effects. Could they have been prevented? How? What do we do now?


Extended Grazing And Reduced Stored Feed, Edward N. Ballard Oct 2009

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 …


Stored Feed Needs: How Much? What Quality?, Jeff Lehmkuhler Oct 2009

Stored Feed Needs: How Much? What Quality?, Jeff Lehmkuhler

Kentucky Grazing Conference

Feed resources are the largest variable expense in beef production systems outside the initial investment in the livestock. When we look at Standardized Performance Analysis (SPA) information from Texas and Minnesota, states that are at the extreme from an environment stance, the projected costs for maintaining a beef cow are strikingly similar. It is important to note that these costs include all expenses and opportunity costs. Getting back to the SPA information, in 2007 the annual cost to maintain a cow in Texas was determined to be roughly $590 while the Minnesota value was near $610 or only about $20/cow …


Tall Fescue Grazing Research, Glen Aiken Oct 2009

Tall Fescue Grazing Research, Glen Aiken

Kentucky Grazing Conference

‘Kentucky-31’ tall fescue, like it or hate it, covers 5 million acres of Kentucky and if you do not have it on your farm, it is likely that one of your bordering neighbors does! Tall fescue owes its persistence and productivity in large part to a fungal endophyte that infects most plants. This endophyte produces an array of alkaloids that benefit the plant in tolerating heat, drought, and grazing. Unfortunately, the endophyte also produces ergot alkaloids that can cause “fescue toxicosis” in cattle. Cattle inflicted with toxicosis have reduced dry matter intake, elevated body temperature, and often retain their winter …


Weed Control Options For Pastures, Jon Doran Oct 2009

Weed Control Options For Pastures, Jon Doran

Kentucky Grazing Conference

What is a weed? A pasture or hayfield “weed” is any plant that you deem as being out of place and/or a plant that is decreasing your desired forage production. Weeds may be classified in several ways including broadleaf weeds, woody plants, and undesirable grasses. Besides decreasing forage, weeds can also interfere with forage utilization, grazing distribution, etc. There are several methods available to control weeds and increase production of and access to desirable forages. The three main methods are cultural, mechanical, and chemical. The cultural method is quite simple-a thriving grass stand is an excellent form of weed control …


Our Experiences With Eastern Gamagrass, Tommy R. Yankey Oct 2009

Our Experiences With Eastern Gamagrass, Tommy R. Yankey

Kentucky Grazing Conference

As livestock producers try to reduce their cost of production, many look at ways to reduce their feed costs. Feed costs have been identified as the largest single cost of livestock production, making up 50 to 70% of the total cost of production. Grazing is the cheapest way to feed cattle on a cost per pound of nutrient basis.