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weed Seedbank Dynamics and Composition of Northern Great Plains Cropping Sytems: Author: Harbuck, Kristin Suzanne Bates; Date: 2007-08-15; Program: Land Resources and Environmental Sciences; Abstract: With a growing concern about sustainability of agricultural production systems, interest in integrated weed management systems has increased. Increasing the understanding of weed seedbank dynamics will improve efficiency of management. The objectives of this study were to 1) quantify weed seedbank dynamics in response to seed density and burial depth, 2) determine weed seedbank decay at varying seed densities and burial depths, 3) quantify weed seed predation in wheat and tilled fallow fields, and 4) characterize and compare weed seedbanks in organic and conventional no-tillage production fiel...; Download File | View full details

The establishment, drought tolerance, and weed suppression potential of multispecies sod: Author: Stark, Jennifer Grace; Date: 2009-05-15; Program: Land Rehabilitation; Abstract: Re-seeding is a frequently used technique to revegetate disturbed areas, but often leaves bare ground prone to weed invasion. Mixtures of drought tolerant or native species in sod could be used as an alternative to seed to provide rapid establishment of desirable plant communities that may potentially reduce weed emergence, survival, and productivity. Additionally, the reinforcement material required to aid transport of multispecies sod could further contribute to weed suppression and sod establishment. The objective of this study was to evaluate the weed suppression and establishment potentia...; Download File | View full details

Diversity, Spatial Patterns, and Competition in Conventional No-Tillage and Organically Managed Spring Wheat Systems in Montana: Author: Pollnac, Fredric Winslow; Date: 2007-05-15; Program: Land Resources and Environmental Sciences; Abstract: The long term sustainability of agricultural systems has become a major concern. In light of this, interest in integrated weed management systems has increased. A better understanding of ecological processes occurring within the weed community might yield insights into how to control weeds while reducing chemical inputs. The objectives of this study were to 1) compare weed species richness and diversity between conventional no-till and organic spring wheat systems, 2) compare spatial patterns of the weed community between these two systems, and 3) examine the joint effects of weed species rich...; Download File | View full details

Toadflax, Fire, Mecinus Janthinus, and Compensatory Growth: Author: Anthony, Antoinette; Date: 2005-08-15; Program: Land Resources and Environmental Sciences; Abstract: Dalmatian toadflax is a noxious weed of the western United States. In western Montana it invades in the foothills zone where bunchgrasses (Agropyron spicatum and Festuca idahoensis) meet low forests (Pinus ponderosa and Pseudosuga menziesii). Our results show that wildfire strengthens toadflax, probably at the expense of native grasses. The stem boring weevil, Mecinus janthinus, is being tested as the most likely biocontrol agent for the weed. On our toadflax infested sites in the Agropyron spicatum/Pinus ponderosa zone Mecinus established, survived, and spread slowly (2-4m/yr) for two years f...; Download File | View full details

Establishment and seed production of native forbs used in restoration: Author: Wiese, Jessica Linsay; Date: 2009-08-15; Program: Land Resources and Environmental Sciences; Abstract: The importance of incorporating native wildflowers into seed mixtures for disturbed land revegetation projects is widely known and accepted. However, further assessment of weed management approaches is a necessary step to successfully establish and produce native wildflower seed. We examined the impact of pre and post-emergence herbicides alone and in combination with hand weeding on 5 wildflower species [slender white prairie clover (Dalea candida(Michx). ex Willd), blanketflower (Gaillardia aristata Pursh), fuzzy tongue penstemon (Penstemon eriantherus Pursh var. eriantherus), silverleaf pha...; Download File | View full details

Design, fabrication, and testing of the van der Pauw piezoresistive structure for pressure sensing: Author: Cassel, Robert Douglas; Date: 2008-05-15; Program: Mechanical Engineering; Abstract: The project characterizes a piezoresistive sensor under variations of both size and orientation with respect to the silicon crystal lattice for its application to MEMS pressure sensing. The sensor to be studied is a four-terminal piezoresistive sensor commonly referred to as a van der Pauw (VDP) structure. The VDP sensor is used primarily in sheet resistance measurements, but has also been determined to be useful in determining the stress components at a point on (100) and (111) silicon wafer surfaces. In a previous study, our team has determined the relation between the biaxial stress state a...; Download File | View full details

Axial capacity of piles supported on intermediate geomaterials: Author: Brooks, Heather Margaret; Date: 2008-08-15; Program: Civil Engineering; Abstract: Pile foundations used to support bridges and other structures are designed and installed to sustain axial and lateral loads without failing in bearing capacity and without undergoing excessive movements. The axial load-carrying capacity of a driven pile is derived from friction or adhesion along the pile shaft and by compressive resistance at the pile tip. There are well established analytical methods for evaluating pile capacity and for predicting pile driving characteristics for cohesive soil, cohesionless soil, and rock. However, past experience indicates these methods may not be reliable f...; Download File | View full details

Integrated Management of Cercospora Leaf Spot on Sugar Beet: Author: Larson, Ben James; Date: 2004-05-15; Program: Plant Pathology; Abstract: Cercospora leaf spot (CLS), caused by Cercospora beticola, is the most important foliar disease of sugar beets in Montana. Losses in research plots ranging from 5-15 metric tons per hectare and 0.5-1.5% lower sugar in the last 7 years. Increased levels of storage rot, sugar impurities, and loss of sugar to molasses have also contributed to losses. Current management strategies are heavily dependent upon the application of a few registered fungicides. Continued use of these fungicides is threatened by registration removal through the Food Quality Protection Act of 1996, and the development of f...; Download File | View full details

Dead-Set Against It? Thoughts of Death Can Promote resistance to Attitude Change: Author: Dood, Tiffany Lee; Date: 2007-05-15; Program: Applied Psychology; Abstract: Terror Management Theory (TMT) argues that people experience an underlying sense of 'terror' when presented with their own mortality, causing them to more strongly defend their ideals (Greenberg, Pyszczynski, & Solomon, 2000). Although much support exists for this idea, prior research has not specifically investigated whether mortality reminders will enhance individuals' resistance to persuasive attempts that are counter to their existing attitudes. Thus, the purpose of the current study was to examine how reminders of individuals' mortality affect participants' attitudes towards persuasiv...; Download File | View full details

No-Till Perennial Forage Establishment in Western Montana: Author: Strauch, Oscar Eduardo; Date: 2005-12-15; Program: Animal and Range Sciences; Abstract: No-till forages offer an opportunity to convert old forage stands to high-yielding pastures. Sod, soil water control and forage species are key factors in determining the success of no-till application. Experiment 1 was conducted to determine optimum vegetation control and moisture on alfalfa in the spring. In experiment 2, adapted grasses and legumes were compared under tilled and no-till seedbed preparation to assess their performance. In Experiment 1, the effects of timing of glyphosate [N-(phosphonomethyl) glycine] application, two alfalfa cultivars (including a roundup ready alfalfa) and ...; Download File | View full details

Wheat Yield Prediction Modeling for Localized Optimization of Fertilizer and Herbicide Application: Author: Wagner, Nicole Catherine; Date: 2004-08-15; Program: Land Resources and Environmental Sciences; Abstract: The specific goal of this thesis was the development of a five-variable dryland wheat yield prediction model for the optimal localized variable-rate management of fertilizer and herbicide considering varying levels of available water and weed infestation. The motivation for this work was to increase on-farm net return and reduce off-target chemical effects. The five most influential predictor variables of wheat yield were investigated: wheat density, wild oat density, nitrogen fertilizer rate, herbicide rate, and water level Previously collected field data sets that included dryland wheat yiel...; Download File | View full details

The Effects of Carbohydrate on Inflammation following an Acute Bout of resistance Exercise: Author: Pearson, Sherri Diane; Date: 2006-12-15; Program: Health and Human Development; Abstract: The immune response to inflammation involves the release of cytokines, which determine the intensity and duration of the immune response (Kuby, 1997). The cytokine interleukin-6 (IL-6), functions as a negative feedback signal that turns off pro-inflammatory mediators during the immune response. IL-6 also initiates the release of CRP, which induces inflammation. Therefore, IL-6 is known as both a pro and anti-inflammatory mediator of the immune response. IL-6 is released during the immune response to inflammation. IL-6 peaks about 8 hours after an eccentric exercise session that induces muscle...; Download File | View full details

Discovery and Distribution of Root Lesion Nematode, Pratylenchus neglectus, in Montana: Author: Johnson, Wendy Ann; Date: 2007-12-15; Program: Plant Pathology; Abstract: Root lesion nematodes (Pratylenchus neglectus and P. thornei) cause significant yield losses for wheat worldwide. To assess the prevalence of root lesion nematodes in Montana, soil samples were collected statewide in 2006 and 2007. In 2006, P. neglectus was found in 12 of the 17 counties and in 41% of all field samples surveyed. In 2007, P. neglectus was found in 11 of 15 counties and in 37% of all field samples surveyed. No P. thornei was found. For fields having root lesion nematode in 2006, P. neglectus mean population densities were 1213 nematodes/kg soil with population densities exceedin...; Download File | View full details

The Use of GPS to Predict Energy Expenditure for Outdoor Walking: Author: McKenzie, James Michael; Date: 2007-05-15; Program: Health and Human Development; Abstract: The purpose of this study was to determine the ability of GPS-reported position and elevation to estimate actual energy expenditure (EEACT) for outdoor walking. An accurate method for assessing EE in the field could greatly influence the scope of future studies of free-living activities. Thirteen subjects (8 male, 5 female) completed a 2303 m course of varying grades at slow and fast self-selected paces. Data from a portable metabolic unit was used to compare the GPS-predicted EE (EEGPS). Calculations of EEGPS were made by compiling an equation accounting for ground speed, grade, (Minetti, et ...; Download File | View full details

Rationalism and D. H. Lawrence: A 21st Century Perspective: Author: Rehan, Naveed; Date: 2004-05-15; Program: English; Abstract: Since the time of the Greek philosopher Plato, Western intellectuals have relied on logos or "the word" to make philosophical propositions about the world humans find themselves in. Logos or "the word" has generally been privileged over mythos or pathos, denoting emotion and feeling. This privileging has sometimes been challenged by intellectuals within the Western tradition. D. H. Lawrence was the most vocal and passionate writer to do so in modern times. This text traces the development of rationalism in the Western tradition and Lawrence's resistance to it. It also ...; Download File | View full details

African American Suffering and Suicide Under Slavery: Author: Kneeland, Linda Kay; Date: 2006-05-15; Program: History; Abstract: While the suffering of slaves in the antebellum American South is common knowledge, what is not so commonly known is the suicide rate among those slaves. How did slaves respond to the suffering they were forced to undergo? While some slaves did choose suicide, the rates appear to be surprisingly low. This is consistent with suicide rates for Africa and for people of African descent living in other areas of the world, and further supports the theory that a low suicide rate is an element of African culture. The overwhelming majority of African-American slaves chose to deal with their suffering t...; Download File | View full details

A descriptive study of childhood obesity monitoring practices used by Montana pediatric providers: Author: Schwarzkopf, Nancy Denise; Date: 2008-05-15; Program: Nursing; Abstract: INTRODUCTION: The global prevalence of childhood obesity is increasing. Overweight children face risks of compromised physical and mental well being, increased incidence of disease processes, and increased risk of adult obesity. Pediatric providers play a unique role in reversing the prevalence of obesity, yet there is little understanding of what practices are utilized to monitor children's weight. PROBLEM: Identifying children who are obese or are at risk for becoming obese may rely on evidence based weight monitoring practices. For many providers there may be a gap in knowledge regarding r...; Download File | View full details

Using Ecological Theory to Guide the Implementation of Augmentative Restoration: Author: Bard, Erin Christina; Date: 2004-05-15; Program: Land Resources and Environmental Sciences; Abstract: Invasive organisms are now considered the second worst threat to native biological biodiversity, behind habitat loss and fragmentation. Successful control of invasive plants can have unexpected impacts on native plants and wildland systems. Therefore, it is important for managers of invasive species to become increasingly concerned with more than target invaders, but also ecological mechanisms and processes like invasion resistance, environmental heterogeneity, and succession that direct plant community dynamics. Augmentative restoration is a management approach that augments existing ecologic...; Download File | View full details

Determining the Suitability of Native Grasses for Highway Revegetation Sod: Author: Stott, Lance Vear; Date: 2007-08-15; Program: Plant Sciences; Abstract: In past years, the California Department of Transportation (Caltrans) has used hydroseeding, imprinting and drill seeding methods to revegetate highway construction sites with varying degrees of success. Ecological concerns have led researchers to consider using native species for revegetation as they are better suited to local environments, require less maintenance and do not pose a threat to adjacent ecosystems. In addition, the urgency for stabilizing areas of high erosion potential and that of establishing native plant cover quickly in order to prevent non-native plant and weed establishme...; Download File | View full details

The Population Dynamics of Tansy Ragwort (Senecio jacobaea) in Northwestern Montana: Author: Bauer, Brad David; Date: 2006-05-15; Program: Land Resources and Environmental Sciences; Abstract: Following the Little Wolf wildfire of 1994 in northwestern Montana, tansy ragwort (Senecio jacobaea) was classified as a state noxious weed. This project aimed to help prioritize the management of populations of tansy ragwort through an understanding of the biotic and abiotic factors influencing the species. Using field collected data and by constructing a prediction model, we found that the most important variables to predict the presence of tansy ragwort were distance from the main road, slope, cosine of aspect, and several remotely sensed LANDSAT ETM+ bands. Most of the predicted occurrence...; Download File | View full details

Sequential cattle and sheep grazing for Spotted Knapweed control: Author: Henderson, Stacee Lyn; Date: 2008-12-15; Program: Animal and Range Sciences; Abstract: Spotted knapweed (Centaurea stoebe L.) infests millions of hectares of native rangeland in North America. Spotted knapweed creates large monocultures, which decreases biodiversity, reduces livestock and wildlife forage, and increases surface water runoff and soil erosion. Sheep are an effective tool for controlling spotted knapweed and have been widely used on cattle ranches for weed control. However, cattle producers are concerned that sheep will over-utilize desirable graminoids. Therefore, research is needed to determine an effective grazing strategy using cattle and sheep that will adverse...; Download File | View full details

Belowground Competition and Response to Defoliation of Centaurea maculosa and Two Native Grasses: Author: Sartor, Karla Anne; Date: 2005-08-15; Program: Land Resources and Environmental Sciences; Abstract: Invasion of native rangelands in the western United States has serious ecological and economic effects. Understanding the mechanisms behind invasion of Centaurea maculosa (spotted knapweed) is necessary to effectively manage this species. Arbuscular mycorrhizae (AM), which are a type of plant fungal symbiosis, are ubiquitous in grasslands. My research explores the role of AM for increasing the competitive ability of C. maculosa. A greenhouse experiment tested the effects of AM fungi and neighbor species growth of C. maculosa, Festuca idahoensis (Idaho fescue) and Pseudoroegneria spicata (blueb...; Download File | View full details

Vegetative reproduction and the integrated management of Canada thistle: Author: Sciegienka, Joanna Katarzyna; Date: 2009-05-15; Program: Land Rehabilitation; Abstract: Canada thistle (Cirsium arvense (L.) Scop.) is an aggressive, introduced creeping perennial weed that flourishes in a wide variety of environments. Its deep, creeping root system and colony forming tendencies make it one of the most difficult weeds to control. A strategy that incorporates a better understanding of the biology of Canada thistle into the development of an integrated management plan that includes herbicides and biological control could help reduce the dispersal and impact of this species. The objectives of this work were to: 1) determine how Canada thistle emergence and growth ar...; Download File | View full details

Map-based Tests on Controls of Anabranch River Character on the Lower Yellowstone River: Author: Jenkins, Patricia Ann; Date: 2007-12-15; Program: Earth Sciences; Abstract: Processes responsible for the formation of anabranched river systems are poorly understood. The Yellowstone River, Montana, is a major unimpounded river with over 800 km of anabranched channel. There are from one to seven channels per reach. Current literature identifies at least seven variables that may influence anabranch river character: tributary junctions, bedrock lithology, vegetation, sediment pulses, debris/ice jams, water loss from stream (to groundwater or irrigation withdrawal) and tectonism. Two variables, tributary junctions, bedrock lithology (measured by relative bedrock hardnes...; Download File | View full details

Composition and Aleche: Native American Education, Scholarship and the Pedagogy of John Dewey: Author: Jenkins, Nathan Joseph; Date: 2005-05-15; Program: English; Abstract: This thesis approaches the historical and contemporary education of Native Americans in order to analyze and combat the American academic system's failure to educate Native students. The chapters cover 1) boarding schools aims and student resistance, 2) problems still faced by Native American students, and 3) possible solutions to these problems. Chapters 1 and 2 give an overview of history and research done by educators and scholars. Chapter 3 is a combination of suggestions by educators of Native students and John Dewey. The first sections demonstrate problems and voids in academia, and the ...; Download File | View full details

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