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Flora Of The Gurvan Saykhan Mountains, Tseden Jamsran, Batlai Oyuntsetseg, Radnaakhand Tungalag Jan 2005

Flora Of The Gurvan Saykhan Mountains, Tseden Jamsran, Batlai Oyuntsetseg, Radnaakhand Tungalag

Erforschung biologischer Ressourcen der Mongolei / Exploration into the Biological Resources of Mongolia, ISSN 0440-1298

Although two major books have been published on the Mongolian flora regional data are often still lacking due to the vast expanses of the country. Therefore we used published information and data from our own fieldwork to compile a relatively comprehensive inventory of the flora of the Gobi Gurvan Saykhan mountains in southern Mongolia.


First Record Of An Adult Male Evening Bat From Kansas, Clay R. Davis, Justin G. Boyles Jan 2005

First Record Of An Adult Male Evening Bat From Kansas, Clay R. Davis, Justin G. Boyles

The Prairie Naturalist

The evening bat (Nycticeius humeralis) occurs throughout the eastern and southeastern United States and into extreme northeastern Mexico, approximately 42° to 18° N latitude (Watkins and Shump 1981). Although records of females are common, records of adult male evening bats are rare in the northern portion of the species range (Watkins 1969, Watkins 1972). Jones et al. (1967) suggested that adult males might not accompany females to at least some parts of the parturient range. As part of a larger study (Davis 2003) we surveyed bats on Fort Leavenworth Military Reservation (FLMR), Leavenworth County, Kansas in July 2002 …


Science-Based Organic Farming 2005: Toward Local And Secure Food Systems, Charles A. Francis, Twyla Hansen, Peter Skelton Jan 2005

Science-Based Organic Farming 2005: Toward Local And Secure Food Systems, Charles A. Francis, Twyla Hansen, Peter Skelton

Publications from the Center for Applied Rural Innovation (CARI)

Organic farming includes growing food and fiber — animals, agronomic crops, horticultural fruits and vegetables, related products — as one dynamic and rapidly evolving component of our complex U.S. food system. Even as more farmers are moving toward organic certification and participation in an environmentally sound and economically lucrative market, questions arise about the long-term social impacts and sustainability of a set of practices that has gone from a movement to an industry. Consolidations in the organic trade have brought multinational corporations to the table, as they have observed a grassroots activity that has grown by 20% per year for …


Plant Functional Group Diversity As A Mechanism For Invasion Resistance, Monica L. Pokorny, Roger L. Sheley, Catherine A. Zabinski, Richard E. Engel, Tony J. Svejcar, John J. Borkowski Jan 2005

Plant Functional Group Diversity As A Mechanism For Invasion Resistance, Monica L. Pokorny, Roger L. Sheley, Catherine A. Zabinski, Richard E. Engel, Tony J. Svejcar, John J. Borkowski

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A commonly cited mechanism for invasion resistance is more complete resource use by diverse plant assemblages with maximum niche complementarity. We investigated the invasion resistance of several plant functional groups against the nonindigenous forb Spotted knapweed (Centaurea maculosa). The study consisted of a factorial combination of seven functional group removals (groups singularly or in combination) and two C. maculosa treatments (addition vs. no addition) applied in a randomized complete block design replicated four times at each of two sites.


Integration Of Co 2 Flux And Remotelysensed Data For Primary Production And Ecosystem Respiration Analyses In The Northern Great Plains: Potential For Quantitative Spatial Extrapolation, Tagir G. Gilmanov, Larry L. Tieszen, Bruce K. Wylie, Larry B. Flanagan, Albert B. Frank, Marshall R. Haferkamp, Tilden P. Meyers, Jack A. Morgan Jan 2005

Integration Of Co 2 Flux And Remotelysensed Data For Primary Production And Ecosystem Respiration Analyses In The Northern Great Plains: Potential For Quantitative Spatial Extrapolation, Tagir G. Gilmanov, Larry L. Tieszen, Bruce K. Wylie, Larry B. Flanagan, Albert B. Frank, Marshall R. Haferkamp, Tilden P. Meyers, Jack A. Morgan

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Aim Extrapolation of tower CO2 fluxes will be greatly facilitated if robust relationships between flux components and remotely sensed factors are established. Long-term measurements at five Northern Great Plains locations were used to obtain relationships between CO2 fluxes and photosynthetically active radiation (Q), other on-site factors, and Normalized Difference Vegetation Index (NDVI) from the SPOT VEGETATION data set.


Plant Community Field Surveys In Eastern Nebraska Project Final Report, Alicia Admiraal Jan 2005

Plant Community Field Surveys In Eastern Nebraska Project Final Report, Alicia Admiraal

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

This project was completed as part of the Nebraska Game and Parks Commission’s (NGPC) State Wildlife Comprehensive Conservation Plan. As part of this project, inventory and assessment of native plant communities and at-risk habitats throughout the state of Nebraska is necessary. This report describes the field inventories of native grasslands and other plant communities conducted during the 2004 field season for the Elkhorn River valley in Madison, Stanton and Dodge counties, and the Platte River valley between the towns of Columbus and Schuyler, in Platte and Colfax counties. Funding for the project was provided by the US Fish and Wildlife …


2005 Plant Community Field Surveys In Western Nebraska, Robert F. Steinauer Jan 2005

2005 Plant Community Field Surveys In Western Nebraska, Robert F. Steinauer

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

These surveys were undertaken to provide biological data for the Nebraska Game and Parks Commission’s (NGPC) Nebraska Natural Legacy Action Plan. The specific intent was to identify, map, and give quality rankings to large blocks of privately-owned native plant communities within the survey area. In 2005, the surveys focused on Keith, Deuel, Cheyenne, Kimball, Banner, and Scotts Bluff counties, Sioux, Dawes and Sheridan counties north of the Pine Ridge, and Garden County south of the North Platte River.


Rich Mesic Forests: Edaphic And Physiographic Drivers Of Community Variation In Western Massachusetts, J. Bellemare, G. Motzkin, D. R. Foster Jan 2005

Rich Mesic Forests: Edaphic And Physiographic Drivers Of Community Variation In Western Massachusetts, J. Bellemare, G. Motzkin, D. R. Foster

Biological Sciences: Faculty Publications

Rich Mesic Forest, a Northeastern variant of the species-rich Mixed Mesophytic Forest association of eastern North America, is an Acer saccharum-dominated forest type typically associated with calcareous bedrock and nutrient-rich, mull soils. Rich Mesic Forest (RMF) is a priority for conservation in the Northeast due to its limited areal extent, high plant species richness, and numerous rare taxa, yet the community characteristics and environmental correlates of this forest type are incompletely understood. This study undertook a quantitative classification of RMF of the northeastern edge of the Berkshire Plateau in western Massachusetts. Cluster analysis of data from ten sites identified two …


Sediment Loading And Water Quality Of Field Run-Off Water, J. S. Mcconnell, J. D. Mattice, B. W. Skulman, C. K. Bryant, M. Mozaffari Jan 2005

Sediment Loading And Water Quality Of Field Run-Off Water, J. S. Mcconnell, J. D. Mattice, B. W. Skulman, C. K. Bryant, M. Mozaffari

Journal of the Arkansas Academy of Science

Intensive tillage is commonly employed in many agronomic production systems in the United States. Tillage operations may include disking the field, re-smoothing the soil, seedbed formation, reducing the seedbeds, and shallow cultivation for weed control. Tillage practices in conjunction with rainfall have been linked to soil erosion, which may adversely affect the environment. The soil erosion dynamics of two large-scale production cotton fields that utilized both modern-conventional and conservation-tillage technology were examined. Studies were conducted in the cotton-producing region of southeast Arkansas in the Bayou Bartholomew watershed. Bayou Bartholomew is currently listed by the United States Environmental Protection Agency as …


Genetic Variation In Ustilago Bullata: Molecular Genetic Markers And Virulence On Bromus Tectorum Host Lines, Mikel Stevens, Daniel J. Fairbanks, Susan E. Meyer, David L. Nelson, Suzette Clement, Jennifer Waters Jan 2005

Genetic Variation In Ustilago Bullata: Molecular Genetic Markers And Virulence On Bromus Tectorum Host Lines, Mikel Stevens, Daniel J. Fairbanks, Susan E. Meyer, David L. Nelson, Suzette Clement, Jennifer Waters

Faculty Publications

The pathogen Ustilago bullata often causes epidemic levels of head smut disease in Intermountain populations of the inbreeding annual grass Bromus tectorum. We examined patterns of genetic variation for virulence and for amplified fragment length polymorphism (AFLP) markers in four U. bullata populations on B. tectorum in northern Utah and southern Nevada. Patterns of disease incidence generally supported a genefor-gene model for virulence and resistance in this pathosystem. Most host lines were susceptible to most or all paired isolates included in cross-inoculation tests, but we found evidence for the existence of four avirulence genes. Host lines with alleles conferring resistance …


Response Of Sagebrush Steppe Species To Elevated Co2 And Soil Temperature, Melissa S. Lucash, Blake Farnsworth, William E. Winner Jan 2005

Response Of Sagebrush Steppe Species To Elevated Co2 And Soil Temperature, Melissa S. Lucash, Blake Farnsworth, William E. Winner

Environmental Science and Management Faculty Publications and Presentations

Elevated atmospheric CO2 may cause long-term changes in the productivity and species composition of the sagebrush steppe. Few studies, however, have evaluated the effects of increased CO2 on growth and physiology of species important to this ecosystem. Since the response of plants to elevated CO2 may be limited by environmental factors, soil temperature was also examined to determine if low soil temperatures limit CO2 response. To determine how CO2 and soil temperature affect the growth of species native to the sagebrush steppe, bottlebrush squirreltail [Elymus elymoides (Raf.) Swezey], Thurber needlegrass (Stipa thurberiana Piper), …


From Metchnikoff To Monsanto And Beyond: The Path Of Microbial Control, Jeffrey C. Lord Jan 2005

From Metchnikoff To Monsanto And Beyond: The Path Of Microbial Control, Jeffrey C. Lord

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

In 125 years since Metchnikoff proposed the use of Metarhizium anisopliae to control the wheat cockchafer and brought about the first field trials, microbial control has progressed from the application of naturalists’ observations to biotechnology and precision delivery. This review highlights major milestones in its evolution and presents a perspective on its current direction. Fungal pathogens, the most eye-catching agents, dominated the early period, but major mycological control efforts for chinch bugs and citrus pests in the US had questionable success, and interest waned. The discoveries of Bacillus popilliae and Bacillus thuringiensis began the era of practical and commercially viable …


Key Grazing Levels (Foo Targets) For Pasture And Sheep Management, Department Of Agriculture, Western Australia Jan 2005

Key Grazing Levels (Foo Targets) For Pasture And Sheep Management, Department Of Agriculture, Western Australia

Animal production and livestock published reports

Food On Offer (FOO) is the amount of pasture in front of an animal, and is measured in kilograms Dry Matter per hectare. Managing pastures to key grazing levels - or FOO targets - can result in improved production of grazing systems in Mediterranean environments which are characterized by slow winter growth, peak spring growth and dry summers. These targets vary according to what production response is required.

This information sheet illustrates key target FOO for sheep grazing annual pastures during autumn and spring.


Processing Of Yield Map Data, J. L. Ping, Achim R. Dobermann Jan 2005

Processing Of Yield Map Data, J. L. Ping, Achim R. Dobermann

Department of Agronomy and Horticulture: Faculty Publications

Yield maps reflect systematic and random sources of yield variation as well as numerous errors caused by the harvest and mapping procedures used. A general framework for processing of multi-year yield map data was developed. Steps included (1) raw data screening, (2) standardization, (3) interpolation, (4) classification of multi-year yield maps, (5) post-classification spatial filtering to create spatially contiguous yield classes, and (6) statistical evaluation of classification results. The techniques developed allow more objective mapping of yield zones, which are an important data layer in algorithms for prescribing variable rates of production inputs.


Use Of The Hybrid-Maize Model To Improve Management Decisions, Achim R. Dobermann, Haishun Yang, Daniel T. Walters, Kenneth G. Cassman Jan 2005

Use Of The Hybrid-Maize Model To Improve Management Decisions, Achim R. Dobermann, Haishun Yang, Daniel T. Walters, Kenneth G. Cassman

Department of Agronomy and Horticulture: Faculty Publications

Yield potential and yield gaps

Basic structure of Hybrid-Maize

Model inputs

Model applications

Validation, uncertainties & future improvements


Patterns Of Plant Species Diversity In Remnant And Restored Tallgrass Prairies, H. Wayne Polley, Justin D. Derner, Brian J. Wilsey Jan 2005

Patterns Of Plant Species Diversity In Remnant And Restored Tallgrass Prairies, H. Wayne Polley, Justin D. Derner, Brian J. Wilsey

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

To restore diversity of native vegetation, we must understand factors responsible for diversity in targeted communities. These factors operate at different spatial scales and may affect the number and relative abundances of species differently. We measured diversity of plant species and functional groups of species in replicated plots within paired restored and remnant (relic) tallgrass prairies at three locations in central Texas, U.S.A.


Preparations Of Spherical Polymeric Particles From Tanzanian Cashew Nut Shell Liquid By Suspension Polymerization, L L Mkayula, Y M M Makame, T H Matechi Dec 2004

Preparations Of Spherical Polymeric Particles From Tanzanian Cashew Nut Shell Liquid By Suspension Polymerization, L L Mkayula, Y M M Makame, T H Matechi

Tanzania Journal of Science

Spherical Polymeric Particles (SPP) have been prepared from Tanzanian Cashew Nut Shell Liquid (CNSL) by suspension polymerization technique involving either step-growth or chain- growth polymerization mechanisms. The sizes of the SPP, which ranged from 0.1 to 2.0 mm were strongly influenced by the amounts of stabilizers in polymerization recipes used. The particles showed variable surface areas, indicative of the presence of pores in some of the preparations and the highest surface area recorded was about 260 m2g-1. The particles were found to exhibit Langmuir-type adsorption isotherms with saturation capacity of about 9.0 and 44.2 mg/g for Na+ and Ca2+, respectively. …


Atrazine Runoff In The Blue River Basin: Geomorphology, Rainfall, And Agronomic Practices, Kundan Dhakal Dec 2004

Atrazine Runoff In The Blue River Basin: Geomorphology, Rainfall, And Agronomic Practices, Kundan Dhakal

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Atrazine concentrations in the Big Blue River Basin (BRB) in Nebraska and Kansas periodically exceed the U.S. EPA Maximum Contaminant Level (MCL) of 3 µg L-1. The present study is focused on watershed variables influencing surface runoff of atrazine. The assessment includes the impact of corn and sorghum planting progress (indicating atrazine application), rainfall, antecedent soil water content, and soil restrictive layer on stream-measured weekly atrazine load in independent BRB subwatersheds for 1997 - 2004. Maximum atrazine loading occurred after most of the corn had been planted but during sorghum planting from mid-May to early June, immediately following …


The Prairie Naturalist Volume 36, No.4 December 2004 Dec 2004

The Prairie Naturalist Volume 36, No.4 December 2004

The Prairie Naturalist

ROADSIDE BIAS IN POINT COUNT SURVEYS AT ARROWWOOD NATIONAL WILDLIFE REFUGE, NORTH DAKOTA ▪ J. S. Dieni and P. Scherr

HISTORY OF GREATER SAGE-GROUSE IN THE DAKOTAS: DISTRIBUTION AND POPULATION TRENDS ▪ . J. T. Smith, L. D. Flake, K. F. Higgins, and G. D. Kobriger

PATCH USE BY A MONOPHAGOUS HERBIVORE IN FRAGMENTED PRAIRIE LANDSCAPES ▪ . M. J. St. Pierre and S. D. Hendrix

SNOWSHOE HARE OCCURRENCE AND WINTER HABITAT ON THE MISSOURI COTEAU IN NORTH DAKOTA ▪ R. K. Murphy 243

HIGH ABUNDANCE OF NESTING LONG-EARED OWLS IN NORTH DAKOTA ▪ R. K. Murphy, L. J. Rosenfield, …


2004 Forage Spokesperson Contestants, James Chestnut, Jimmy May, Steve Meredith, Bill Payne Oct 2004

2004 Forage Spokesperson Contestants, James Chestnut, Jimmy May, Steve Meredith, Bill Payne

Kentucky Grazing Conference

No abstract provided.


Strategies For Reducing Stored Feed Requirements, Don Ball Oct 2004

Strategies For Reducing Stored Feed Requirements, Don Ball

Kentucky Grazing Conference

A basic, desirable goal for virtually any livestock producer is to minimize stored feed requirements. It is less expensive to have livestock harvest forage for themselves by grazing than to harvest it for them; therefore, the greater the extent to which pasture can be used to provide nutrition, the more profitable a livestock operation will generally be. Thus, it is worthwhile to consider all options that might be available for reducing stored feed needs.


Stocking Decisions: They Make Or Break You, Glen E. Aiken Oct 2004

Stocking Decisions: They Make Or Break You, Glen E. Aiken

Kentucky Grazing Conference

Decisions on species and variety of forage to plant and manage are economically critical because it establishes the potential to meet a particular production goal. However, the stocking rate used to graze these forages is more critical because it ultimately determines if a targeted level of production is reached. Most cattlemen aim for a stocking rate that provides maximum economic return, but it should be emphasized that an economically optimum stocking rate is one that potentially provides sustained economic return. It is obvious that dollar return is not maximized if excessive heavy grazing results in costly pasture renovation, ranging from …


Grazing: Getting From Where You Are To Where You Want To Be, Gary Bates Oct 2004

Grazing: Getting From Where You Are To Where You Want To Be, Gary Bates

Kentucky Grazing Conference

When trying to design a forage and grazing program, producers often try to consider so many factors that it becomes mind-boggling. If basic plant physiology, how and when a forage plant grows is considered, improving a forage program will usually become easier, especially in developing a controlled grazing system. The purpose of a controlled grazing system should be to improve the utilization of the high quality forage produced on the farm. In order to improve this utilization, it is helpful to understand plant growth and quality, and the factors that affect them.


Will Improved Grazing Pay For Extra Fencing And Water Cost?, Ken Johnson Oct 2004

Will Improved Grazing Pay For Extra Fencing And Water Cost?, Ken Johnson

Kentucky Grazing Conference

Expectation is founded on faith, and in faith lays opportunities. I suppose as we look at most farming operations most changes occur from force not by choice. What I propose today and hope to convince most of you; is that here is an opportunity to make more profit, if you’re willing to change and have faith that it will work. Most of us have heard of, if not practiced rotation grazing for a long time. The question many ask, is it worthwhile. Does better grazing management make me any more money? I hope to at least provide some insight as …


Present And Future Tall Fescue Varieties, Timothy D. Phillips Oct 2004

Present And Future Tall Fescue Varieties, Timothy D. Phillips

Kentucky Grazing Conference

Tall fescue has played a key role in forage production over the past century in the USA. It has other uses besides forage applications, such as turf, mine reclamation, and highway rights-of-way, but in this presentation we will focus on forage varieties. Several hundred turf-type tall fescue varieties have been developed over the past 30 years, mainly by private seed companies using material from Reed Funk at Rutgers University in New Jersey. Forage varieties aren’t as numerous. I will discuss some of the older and current forage tall fescue varieties, and finish by discussing the newest varieties, and those that …


Fertilizing Pastures For Profit, Byron Sleugh Oct 2004

Fertilizing Pastures For Profit, Byron Sleugh

Kentucky Grazing Conference

It has been known for centuries that providing certain nutrients to plants is critical for high productivity. The nutrient source and manner in which it is applied may vary, but the desired outcome is the same: high crop yield and quality. Fertilization is the most practical means that producers have to ensure that crops receive the nutrients they need. While increasing fertilizer application and managing pH by liming can lead to increase forage production, your investment should be measured against the potential return. Also, over application of nutrients can potentially cause environmental problems.


Role Of Legumes In Pasture Systems, Garry D. Lacefield Oct 2004

Role Of Legumes In Pasture Systems, Garry D. Lacefield

Kentucky Grazing Conference

Successful livestock programs are dependent on forage programs which supply large quantities of adequate quality, homegrown feed. A major percentage of the feed units for beef (83%) and dairy (61%) cattle come from forages. In addition, forages supply an estimated 91%, 72%, 15% and 99% of the nutrients consumed by sheep and goats, horses, swine and ruminant wildlife, respectively. These values can be put in perspective when we consider that 63% of Kentucky's Agricultural Cash Receipts are from livestock and livestock products. Cash hay accounts for approximately 28% of the total crop value. Hay ranks second only to tobacco in …


Foreword And Kfgc Award Winners [2004], Garry D. Lacefield, Christi L. Forsythe Oct 2004

Foreword And Kfgc Award Winners [2004], Garry D. Lacefield, Christi L. Forsythe

Kentucky Grazing Conference

No abstract provided.


The Prairie Naturalist Volume 36, No.3 September 2004 Sep 2004

The Prairie Naturalist Volume 36, No.3 September 2004

The Prairie Naturalist

OVERLAND MOVEMENTS AND HABITAT USE OF MALLARD BROODS DEPARTING OVERWATER NESTING STRUCTURES ▪ J. D. Stafford, L. D. Flake, and P. W. Mammenga

NEST SITE CHARACTERISTICS OF EASTERN WILD TURKEY IN NORTHEASTERN SOUTH DAKOTA ▪ R. D. Shields and L. D. Flake

WHITE-TAILED DEER INFECTEUWITH STAPHYLOCOCCUS HYICUS IN SOUTH DAKOTA ▪ T. J. Zimmerman, J. A. Jenks, and A. E. Pillatzki

CLOSTRIDIUM PERFRINGENS TYPE A IN A FREE-RANGING FAWN? ▪ T. J. Brinkman, J. A. Jenks, C. S. DePerno, and B. S. Haroldson

BUFFLEHEAD BREEDING ACTIVITY IN SOUTH-CENTRAL NORTH DAKOTA ▪ G. A. Knutsen and J. C. King

POTENTIAL MULTIPLE …


Effects Of Management And Population Size On Genetic Diversity Of Eggert's Sunflower (Helianthus Eggertii; Asteraceae), John Howard Starnes Aug 2004

Effects Of Management And Population Size On Genetic Diversity Of Eggert's Sunflower (Helianthus Eggertii; Asteraceae), John Howard Starnes

Masters Theses & Specialist Projects

Helianthus eggertii (Asteraceae) is a federally threatened sunflower species that typically grows between open woods and barrens. This species has both sexual and asexual modes of reproduction, which can influence the amount of genetic diversity present within and among populations. Maintaining genetic diversity is one of the primary objectives in managing threatened species or populations. Fire and population size may influence genetic diversity. Two Inter-Simple Sequence Repeat Markers (873 and MAO) were used to characterize many important genetic parameters of 17 populations in 2003 and four populations in 2004. This information was used to assess the effectiveness of different conservation …