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Articles 6511 - 6540 of 9407
Full-Text Articles in Entire DC Network
Registration Of ‘Newell’ Smooth Bromegrass, K P. Vogel, R B. Mitchell, B L. Waldron, M R. Haferkamp, J D. Berdahl, D D. Baltensperger, Galen Erickson, T J. Klopfenstein
Registration Of ‘Newell’ Smooth Bromegrass, K P. Vogel, R B. Mitchell, B L. Waldron, M R. Haferkamp, J D. Berdahl, D D. Baltensperger, Galen Erickson, T J. Klopfenstein
Green Canyon Environmental Research Area, Logan Utah
No abstract provided.
Soil Carbon And Nitrogen Mineralization And Crop Parameters In Typical Maize-Bean Intercropping In Western Kenya, Judith A. Odhiambo, Urszula Norton, Emmanuel C. Omondi, Dennis Ashilenje, Jay B. Norton
Soil Carbon And Nitrogen Mineralization And Crop Parameters In Typical Maize-Bean Intercropping In Western Kenya, Judith A. Odhiambo, Urszula Norton, Emmanuel C. Omondi, Dennis Ashilenje, Jay B. Norton
Agricultural and Environmental Sciences Faculty Research
Smallholder farmers in western Kenya who plant maize (Zea mays L.) intercropped with beans (Phaseolus vulgaris L.) face many challenges associated with nutrient-poor soils and weather-related crop failures. In regions where temperatures are favorable, crops are grown twice per year during long and short rainy seasons and in other regions, once per year during one long growing season. Growing crops two times per year necessitates frequent land preparation using inversion-type tillage. Little is known about the impact of current tillage-intensive crop management on annual soil organic matter (SOM) recovery. The aim of this study was to assess changes to soil …
Modeling Mussel Mortality: Investigating The Importance Of Swash And The Potential Implications Of Changing Wave Environments, Shadow Leigh Gulledge
Modeling Mussel Mortality: Investigating The Importance Of Swash And The Potential Implications Of Changing Wave Environments, Shadow Leigh Gulledge
Theses and Dissertations
Rising sea level and increases in temperature are causing biogeographic shifts in intertidal zones and can also lead to shifts in the local vertical zonation of organisms due to changes in body temperature during aerial exposure during low tide. Swash is an important determinant of aerial body temperatures, and vulnerability of intertidal zones to changes in climate could potentially depend on how much and how often animals are cooled by waves. While wave heights (and thus swash) are generally expected to increase with climate change, anthropogenic physical structures, such as breakwaters and wave energy converters, can decrease wave height and …
Climate-Induced Changes In The Germination Phenology Of Boechera Stricta, Samuel Johnson
Climate-Induced Changes In The Germination Phenology Of Boechera Stricta, Samuel Johnson
Theses and Dissertations
Climate change is having demonstrable, worldwide impacts on ecological systems in ways that have modified aspects of organism behavior. Plant phenologies have responded to warmer temperatures in a variety of ways that may have implications for long-term species survival. How germination phenology changes in response to warmer climate is a largely unexplored question yet the ability of a plant to advance or delay germination in unfavorable conditions is critical for survival. Knowing the relative success and timing of germination under different climate regimes is important in understanding whether species can keep pace with the rate of climate change via migration …
The Late Ordovician Biogeochemical Carbon Cycle, John Garrecht Metzger
The Late Ordovician Biogeochemical Carbon Cycle, John Garrecht Metzger
Arts & Sciences Graduate Student Theses and Dissertations
The isotopic composition of the carbonate carbon (δ13Ccarb) is one of the best tools for understanding the biogeochemical carbon cycle through Earth history. δ13Ccarb is also used to chemostratigraphically correlate coeval strata. This dissertation has three main foci that all utilize δ13Ccarb as the common data type. The geologic interval investigated was the Late Ordovician (458-444 Ma) with emphasis on the Guttenberg δ13C excursion, a globally correlated, positive ~3 / event that is ~400 kyr in duration. In the first topic we evaluate post-depositional alteration (i.e., diagenesis) of δ13Ccarb signals. In the second topic, we make reconstructions of sea level …
The Geology And Petrology Of Enigmatic Rhyolites At Graveyard And Gordon Buttes, Mount Hood Quadrangle, Oregon, Elizabeth G. Westby
The Geology And Petrology Of Enigmatic Rhyolites At Graveyard And Gordon Buttes, Mount Hood Quadrangle, Oregon, Elizabeth G. Westby
Dissertations and Theses
Rhyolite lava flows are found at two dome complexes at Graveyard Butte and Gordon Butte, Mount Hood Quadrangle, Oregon. At Graveyard Butte, the White River has cut a winding canyon 150 m deep, exposing at its base, a 40-meter-thick outcrop of flow-banded rhyolite (73 wt.% SiO2, 3.67±0.01 Ma) that laterally extends along the canyon wall for about 1 km. Stratigraphically above the flow-banded rhyolite is locally-erupted iron-rich andesites (lava flows, agglutinate and other pyroclastic rocks as well as clastic debris), a rhyolitic ash-flow tuff (74 wt.% SiO2), and the 2.77±0.36 Ma tholeiitic basalt lava flows of …
Spartanburg Humane Society Data Analysis: Hotspots And Resource Management, Leigh Robertson
Spartanburg Humane Society Data Analysis: Hotspots And Resource Management, Leigh Robertson
Earth and Environmental Sciences Presentations
A data set from the Spartanburg Humane Society was provided with the hope that the use of GIS could show patterns and hotspots of dog and cat pickup locations. With a better understanding of where the majority of the animals come from, the Humane Society can better distribute their man power and resources to help as many homeless animals as possible. According to Beck (1973) the main reasons for stray and abandoned animals is negligence causing pet releases or escapes, and also breeding. Therefore, finding and targeting areas where there are many strays (potentially as a result of a release, …
Structure, Aboveground Biomass, And Soil Characterization Of Avicennia Marina In Eastern Mangrove Lagoon National Park, Abu Dhabi, Tareefa Alsumaiti
Structure, Aboveground Biomass, And Soil Characterization Of Avicennia Marina In Eastern Mangrove Lagoon National Park, Abu Dhabi, Tareefa Alsumaiti
Graduate Theses and Dissertations
Mangrove forests are national treasures of the United Arab Emirates (UAE) and other arid countries with limited forested areas. Mangroves form a crucial part of the coastal ecosystem and provide numerous benefits to society, economy, and especially the environment. Mangrove trees, specifically Avicennia marina, are studied in their native habitat in order to characterize their population structure, aboveground biomass, and soil properties. This study focused on Eastern Mangrove Lagoon National Park in Abu Dhabi, which was the first mangrove protected area to be designated in UAE. In situ measurements were collected to estimate Avicennia marina status, mortality rate (%), …
Carbon Dioxide Emissions From Switchgrass And Cottonwood Grown As Bioenergy Crops In The Lower Mississippi Alluvial Valley, Michele Lea Helton
Carbon Dioxide Emissions From Switchgrass And Cottonwood Grown As Bioenergy Crops In The Lower Mississippi Alluvial Valley, Michele Lea Helton
Graduate Theses and Dissertations
Marginal land of the Lower Mississippi Alluvial Valley (LMAV) has the potential to be utilized for the production of bioenergy feedstocks. Soil respiration is the gaseous emission of carbon dioxide (CO2) from microbes and plant roots in the soil, and these emissions play an important role in the global cycling of carbon. Soil respiration can act as a positive feedback affecting climate change, and has been shown to vary depending on soil moisture, temperature, and vegetation. The objectives of this study where to evaluate the effects of land use [switchgrass (Panicum virgatum), cottonwood (Populus deltoides …
A Hazard Assessment And Proposed Risk Index For Art, Architecture, Archive And Artifact Protection: Case Studies For Assorted International Museums, Clara Jeanene Kirk
A Hazard Assessment And Proposed Risk Index For Art, Architecture, Archive And Artifact Protection: Case Studies For Assorted International Museums, Clara Jeanene Kirk
Graduate Theses and Dissertations
This study proposes a hazard/risk index for environmental, technological, and social hazards that may threaten a museum or other place of cultural storage and accession. This index can be utilized and implemented to measure the risk at the locations of these storage facilities in relationship to their geologic, geographic, environmental, and social settings. A model case study of the 1966 flood of the Arno River and its impact on the city of Florence and the Uffizi Gallery was used as the index focus. From this focus an additional eleven museums and their related risk were assessed. Each index addressed a …
Switchgrass Cultivar, Harvest Frequency, Fertilizer Source, And Irrigation Effects On Near-Surface Soil Properties In West-Central Arkansas, Alayna A. Jacobs
Switchgrass Cultivar, Harvest Frequency, Fertilizer Source, And Irrigation Effects On Near-Surface Soil Properties In West-Central Arkansas, Alayna A. Jacobs
Graduate Theses and Dissertations
Switchgrass (Panicum virgatum L.) has been identified as a model bioenergy feedstock crop and is expected to become an important feedstock for future renewable fuel generation. Agronomic management combinations that maximize monoculture switchgrass yield are generally well understood; however, little is known about corresponding effects of differing switchgrass management combinations on near-surface soil properties. The objective of this research was to determine the residual near-surface soil property effects of three years (2008 to 2011) of consistent management combinations to maximize switchgrass biomass production, including cultivar (‘Alamo’ and ‘Cave-in-Rock’), harvest frequency (1-cut and 2-cut systems per year), fertilizer source (poultry …
Increased Effluent Dosage Effects On Septic System Absorption-Field Products Of Differing Architecture Types, Andrew Richard Gibbons
Increased Effluent Dosage Effects On Septic System Absorption-Field Products Of Differing Architecture Types, Andrew Richard Gibbons
Graduate Theses and Dissertations
Nationwide, approximately 20% of all homes use an on-site septic system as a form of household wastewater treatment. Since karst features are prevalent throughout the Ozark Highlands region of Northwest Arkansas, surface and groundwater resources are susceptible to contamination. Therefore, the objectives of this study were to evaluate the effects of soil condition (i.e., wet and dry) and absorption-field-product architecture type [i.e., chamber, gravel-less-pipe (GLP), polystyrene-aggregate (PSA), and pipe-and-aggregate (PA)] on in-product solution storage and biomat thickness in a profile-limited soil, and to identify the long-term acceptance rate (LTAR) of each product. During Phase I of this study (i.e., March …
Subalklaine Volcanism In The Eastern Basin And Range Province: Examples From The Miocene Mccullough Range Volcanic Field And The Pliocene To Holocene Black Rock Desert Volcanic Field, Racheal Leighann Johnsen
Subalklaine Volcanism In The Eastern Basin And Range Province: Examples From The Miocene Mccullough Range Volcanic Field And The Pliocene To Holocene Black Rock Desert Volcanic Field, Racheal Leighann Johnsen
UNLV Theses, Dissertations, Professional Papers, and Capstones
This dissertation is composed of three papers that apply geologic mapping, whole rock geochemical and isotopic analysis, and mineral chemistry to describe two large, long-lived (~6 million years), and compositionally heterogeneous volcanic fields and posit sources of the rock types present in each. These fields are the McCullough Range in southern Nevada, which was a locus of volcanic activity from ~19 - 12 Ma and the Black Rock Desert volcanic field in west-central Utah, which began forming at ~6 Ma and is still active today, with the most recent eruption occurring ~720 years ago.
Chapter Two is composed of a …
New Early Miocene 40ar/39ar Ages For Nakwai, Northwest Kenya, Africa, And Paleontological Analysis Of Meroehyrax Kyongoi Dentition, Dawn Elena Reynoso
New Early Miocene 40ar/39ar Ages For Nakwai, Northwest Kenya, Africa, And Paleontological Analysis Of Meroehyrax Kyongoi Dentition, Dawn Elena Reynoso
UNLV Theses, Dissertations, Professional Papers, and Capstones
Nakwai is a fossiliferous region in the Turkana Basin of northwestern Kenya. Until recently the only ages for the Nakwai formation were based on biostratigraphic correlation with Losodok; a late Oligocene site located to the north of Nakwai. The new 40Ar/39Ar ages in this study range from 23 Ma to 15 Ma and constrain the upper portions of the Nakwai section to the early Miocene. These ages make it the only securely dated fossil locality in the region that represents the earliest Miocene; all of the other early Miocene fossil localities date back to ~20 Ma or younger. The time …
Groundwater Trend Analysis And Salinity Risk Assessment For The South-West Agricultural Region Of Western Australia, 2007–12, G Paul Raper, Russell Speed, John Andrew Simons, A L. Killen, Andrew Blake, A T. Ryder, Rosemary H. Smith, Grantley Stainer, L Bourke
Groundwater Trend Analysis And Salinity Risk Assessment For The South-West Agricultural Region Of Western Australia, 2007–12, G Paul Raper, Russell Speed, John Andrew Simons, A L. Killen, Andrew Blake, A T. Ryder, Rosemary H. Smith, Grantley Stainer, L Bourke
Resource management technical reports
Dryland salinity is a hydrologically driven land degradation hazard in the south-west agricultural region of Western Australia (WA). Shallow-rooted annual crops and pastures transpire significantly less water than the native vegetation they replaced, leading to an increase in recharge, rising groundwater levels and the development of shallow watertables in areas where often none existed previously. Rising groundwater levels mobilise soluble salts, naturally stored at high concentrations in the regolith. These salts can be concentrated in the root zone of vegetation by evapotranspiration.
Seeing Below The Surface With Electrical Resistivity Tomography: Exploring The Deepest Reaches Of Arkansas' Tallest Prehistoric Mounds, James Robert Zimmer-Dauphinee
Seeing Below The Surface With Electrical Resistivity Tomography: Exploring The Deepest Reaches Of Arkansas' Tallest Prehistoric Mounds, James Robert Zimmer-Dauphinee
Graduate Theses and Dissertations
Despite decades of research and over a century of public interest, the most prominent features at Toltec Mounds Archeological State Park, Mound A and Mound B, remain virtually unexamined by modern archaeological techniques, and poorly understood. The tremendous scale and importance of these mounds makes most standard research methods difficult if not impossible. Electrical Resistivity Tomography, a geophysical technique rarely used in North America, was employed to survey both Mound A and Mound B, resulting in models of the subsurface that provide insights into the construction, modification and condition of the mounds.
Short-Term Effects Of Poultry Litter Or Woodchip Biochar Amendment In A Temperate Zone Agronomic System, Katy Elizabeth Brantley
Short-Term Effects Of Poultry Litter Or Woodchip Biochar Amendment In A Temperate Zone Agronomic System, Katy Elizabeth Brantley
Graduate Theses and Dissertations
Biochar, a charcoal product produced by the anaerobic thermal decomposition of biomass, can provide agronomic benefits when soil applied. However, research is lacking in temperate region soils investigating specific biochar products and their effects on agronomically important crops. A greenhouse study utilizing poultry litter biochar and a field study utilizing pine woodchip biochar were conducted to observe the effects of biochar application to Northwest Arkansas soils on corn growth and nutrient availability. A third experiment investigated poultry litter and pine woodchip biochar influences on soil water retention. In all three experiments, biochar was applied at three rates (0, 5, and …
Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha
Analysis Of Body Shapes Among Barbus Trimaculatus, Barbus Paludinosus And Barbus Jacksonii (Actinopterygii: Cyprinidae) From Malagarasi And Pangani River Basins Based On Geometric Morphometric Method, Chacha J. Mwita, B.G. Kamugisha
Tanzania Journal of Science
This study analyzed variability in body shapes among the small Barbus species of the family Cyprinidae currently occurring in the Malagarasi and Pangani River basins years after uplift of the east African topology. Fish specimens were collected from Songati, Muumbara and Nyamagoma within the Malagarasi River basin; Hale and Pangani fall located on Pangani River. It was found that although the landmarks were placed at the same anatomical regions, significant body shapes variations existed. The relative warps analysis for Barbus trimaculatus and Barbus jacksonii populations from Malagarasi and Pangani wetlands revealed intra-locality variations as for populations from other African countries. …
Range Of Horizontal Transport And Residence Time Of Nitrate In A Mature Karst Vadose Zone, Jiri Kamas, Jiri Bruthans, Helena Vysoka, Miroslav Kovařík
Range Of Horizontal Transport And Residence Time Of Nitrate In A Mature Karst Vadose Zone, Jiri Kamas, Jiri Bruthans, Helena Vysoka, Miroslav Kovařík
International Journal of Speleology
Nitrate concentrations in drips in Amaterska, Spolecnak, and Holstejnska caves situated below a 25 to 120 m thick vadose zone in the Moravian Karst, Central Europe were studied during several periods from 1992. Each cave runs below a land-use boundary between fertilized lands and forest, which enabled study of the range of horizontal components of nitrate transport in the vadose zone. Parts of the fertilized land were turned into grassland in 1998 and 2003, and the cave drips were sampled both prior and after the changes in land use. The mean residence time of nitrate is - 30 m thick …
Utilizing Indicator Of Reduction In Soils Tubes To Affirm A Serpentinitic Hydric Soil On The California Central Coast, Jason Demoss
Utilizing Indicator Of Reduction In Soils Tubes To Affirm A Serpentinitic Hydric Soil On The California Central Coast, Jason Demoss
Natural Resources Management and Environmental Sciences
Wetlands are vital ecosystems that are crucial in maintaining the life of rare and unique soils, plants, and animals. These ecosystems are key players in water storage, water filtration, carbon storage, and harboring unique species. Since the intervention of human development on the Earth’s surface, almost 50% of the Earth’s original wetlands have either been damaged or destroyed. The identification and assessment of both new and old wetlands is crucial in the survival of these precious ecosystems and their conservation. A 3 month-long study was performed to confirm the hydric status of a soil derived from serpentinitic parent material. The …
A Regional Look At Hanpp: Human Consumption Is Increasing, Npp Is Not, Steven W. Running
A Regional Look At Hanpp: Human Consumption Is Increasing, Npp Is Not, Steven W. Running
Ecosystem and Conservation Sciences Faculty Publications
Abdi et al (2014 Environ. Res. Lett. 9 094003), have adapted the concept of comparing supply and demand of annual plant production known as human appropriation of net primary production (HANPP) to a region of the Sahel with rapid population growth. They found that HANPP more than doubled over the study period of 2000–2010, from 19% to 41%, suggesting increasing vulnerability of these populations to food insecurity.
Discovery Of A 240 Million Year Old Nematode Parasite Egg In A Cynodont Coprolite Sheds Light On The Early Origin Of Pinworms In Vertebrates, Jean-Pierre Hugot, Scott Gardner, Victor Borba, Priscilla Araujo, Daniela Leles, Átila Da-Rosa, Juliana Dutra, Luis Fernando Ferreira, Adauto Araújo
Discovery Of A 240 Million Year Old Nematode Parasite Egg In A Cynodont Coprolite Sheds Light On The Early Origin Of Pinworms In Vertebrates, Jean-Pierre Hugot, Scott Gardner, Victor Borba, Priscilla Araujo, Daniela Leles, Átila Da-Rosa, Juliana Dutra, Luis Fernando Ferreira, Adauto Araújo
Harold W. Manter Laboratory of Parasitology: Faculty Publications
Background: We report the discovery of a nematode parasite egg (Nemata: Oxyurida) from a coprolite closely associated with the remains of several species of Cynodontia, dated to 240 million years old. This finding is particularly significant because this is the oldest record of an oxyurid nematode yet discovered, and because the cynodonts are considered a stem-group of the mammals.
Methods: We extracted material from a fully mineralized coprolite by both scraping the surface, and removing fragments from its interior with clean dental instruments used a single time. A single drop of glycerol from a new vial was added as a …
Water Resources And The Historic Wells Of Barbuda: Tradition, Heritage And Hope For A Sustainable Future, Rebecca Boger, Sophia Perdikaris, Amy E. Potter, John Mussington
Water Resources And The Historic Wells Of Barbuda: Tradition, Heritage And Hope For A Sustainable Future, Rebecca Boger, Sophia Perdikaris, Amy E. Potter, John Mussington
Earth, Environment & Sustainability: Faculty Publications
The island of Barbuda has a relatively unique history, land tenure and geography. Unlike its Caribbean counterparts, the island is not suited to large-scale agriculture due to its arid climate and relatively thin soils. Instead, the enslaved and eventually free people of Barbuda developed a complex herding ecology centered on common land ownership. As a result, carefully designed historic wells are strategically located around the island. With the challenges brought about by climate change, an interdisciplinary, international team led by the Barbuda Research Complex is investigating the state of existing water and food resources and examining how the availability and …
Sigma Gamma Epsilon 2014 Service Awards And Projects, Paula Even
Sigma Gamma Epsilon 2014 Service Awards And Projects, Paula Even
The Compass: Earth Science Journal of Sigma Gamma Epsilon
In 2012, the Sigma Gamma Epsilon Chapter Service Award was established. The Chapter Service Award is based upon a non-profit/non-chapter fund raising activity that benefits the department, institution, or community. Four chapters received the award in 2014. Information about their projects as well as other chapters’ service projects is listed as well as the criteria for this award.
Eocene-Oligocene Latitudinal Climate Gradients In North America Inferred From Stable Isotope Ratios In Perissodactyl Tooth Enamel, Alessandro Zanazzi, Emily Judd, Andrew Fletcher, Harold Bryant, Matthew J. Kohn
Eocene-Oligocene Latitudinal Climate Gradients In North America Inferred From Stable Isotope Ratios In Perissodactyl Tooth Enamel, Alessandro Zanazzi, Emily Judd, Andrew Fletcher, Harold Bryant, Matthew J. Kohn
Geosciences Faculty Publications and Presentations
The Eocene-Oligocene transition (~ 34 Ma) was one of the most pronounced episodes of climate change of the Cenozoic. In order to investigate this episode of global climate cooling in North America, we analyzed the carbon and oxygen stable isotope composition of the carbonate component of 19 perissodactyl (horse and rhino) tooth enamel samples from the Eocene-Oligocene rocks of the Cypress Hills Formation (southwestern Saskatchewan, Canada); we then compared the results with previously published data from the US Great Plains (Nebraska, South Dakota, and Wyoming).
Average (± 1σ) perissodactyl enamel δ13C values (vs. V-PDB) in the Eocene (-8.8 …
Can I Afford To Spray For Weeds?, Scott Flynn
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
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
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.
Forage Legumes: Their Importance And Management In Profitable Livestock Systems, Ben M. Goff
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
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.