Agriculture Commons^™

Assessing The Relative Utility Of Models Of Vegetation Dynamics For The Management Of Sagebrush Steppe Rangelands, Paul E. Hosten

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The literature, long-term temporal data sets, and spatial data points surrounding livestock watering pints within rangeland communities wearer used to examine common assumptions and concepts used in models of vegetation dynamics. Of the stability concepts examined, the constancy concept was invalidated using long-term relict area data, whereas long-term data following disturbance indicated that sagebrush-dominated areas could be considered as resilient under circumstances examined. Pioshpere as well as relict and post-disturbance data indicated that the individualistic notion of vegetation change was favored. Species showing the most predictability (based on repeatability of abundance curves, and spatial and temporal serial correlations) were sagebrush …

Behavioral Characteristics Affect Habitat Selection Of Domestic Ruminants, Cody B. Scott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

I evaluated some of the factors affecting livestock distribution by conducting experimental (Chapters II and III) and observational (Chapter IV) studies. In Chapter II, I described the effect of locations of familiar foods and social interactions on choice of feeding location by lambs. Lambs were exposed to a pasture as subgroups of strangers and companions with different dietary habits (i.e., three lambs that preferred milo with three lambs that preferred wheat). Milo was placed on one end and wheat on the other, about 100 m apart. Strangers typically fed in different locations, reflecting dietary preferences. Conversely, companions fed in both …

The Response Of Five Tropical Plant Species To Natural Solar Ultraviolet-B Radiation, Peter S. Searles

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tropical regions currently receive the highest global levels of solar ultraviolet-B radiation (UV-B, 280-320 nm) even without ozone depletion. Thus, the influence of natural, present-day UV-B irradiance in the tropics was examined for five tropical species, including three native rainforest tree species and two economically important species. Solar UV-B radiation conditions were obtained vi using either a UV-B excluding plastic film or a near-ambient UV-B transmitting film in a small clearing on Barro Colorado Island (BCI), Panama (9 ° N). Significant differences were often exhibited as increased foliar UV-B absorbing compounds, increased leaf mass per area, and reduced leaf blade …

Dungpat Microenvironmental Effects On Germination And Establishment Of Crested Wheatgrass, Ghulam Akbar

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Complementary greenhouse and field studies investigated the effects of ambient environmental conditions on cattle dungpat moisture, temperature, nutrient concentration, and crust formation dynamics, which in turn influence seed germination and seedling establishment in dungpats. 'Hycrest' crested wheatgrass [Agropyron desertorum (Fisch. ex Link) X A. cristatum (L.) Gaert.] was used as a representative revegetation species.

After collecting feces from Holstein steers that had been fed crested wheatgrass seeds, uniform dungpats were prepared and placed on two soil types (loam and coarse sand) in containers under three watering treatments (field capacity, 1/2 field capacity, and no water) in the greenhouse. Dungpat …

Competitive Interaction Between Crested Wheatgrasses And Cheatgrass, Mark G. Francis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Current revegetation practices in the lntermountain West include the use of Nordan (Agropyron desertorum) and Hycrest (A. cristatum x desertorum) crested wheatgrass on rangeland susceptible to cheatgrass (Bromus tectorum) invasion, although little quantitative data exists that compares their competitive abilities. We evaluated both the competitive ability of Hycrest and Nordan in two-species mixtures with cheatgrass, and evaluated seedling establishment characteristics for all three species in a greenhouse study. Linear and nonlinear models were developed for a range of densities for each species to predict median above-ground biomass and tiller numbers. In both experiments, increasing …

The Effect Of Black Plastic Mulch Alone And In Combination With Various Types Of Plastic Row Covers On Production Of Sweet Corn, Morteza Jabalameli

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effects of black polyethylene (PE) mulch alone and in combination with plastic film tunnels (Agronet, Reemay, whiteperforated, clear, and clear-slitted) were studied on morphology and yield of sweet corn in North Logan, Utah. Yields of "Miracle" sweet corn (Zea mays L.) were increased significantly by using black PE mulch and with a combination of various types of plastic row covers, as compared to unmulched soil. Standard-growth analysis procedures were conducted to verify responses among treatments. Treatment effects were determined by measuring days to first flowering, ear weight, number of side tillers, cob length, cob circumference, cob fill length, number …

Economic Strategies For White-Tailed Deer And Livestock Production On Central And South Texas Ranches, Will E. Cohen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Recently, hunting and associated recreation have become an important business for Texas landowners. Most ranchers want to realize maximum net return from their investments. This study's objectives were to develop white-tailed deer (Odocoileus virginianus) and livestock enterprise budgets and to determine optimal economic combinations and levels of deer and livestock enterprises to maximize net returns. Questionnaires were mailed to landowners in the Edwards Plateau and South Texas Plains who purchased shooting preserve licenses in 1985. Five hundred and twenty-four ranchers responded (23.4%). Respondents were segregated by enterprises (deer, cattle, sheep, and Angora and Spanish goats) and a 5% …

Mathematical Programming Applications In Agroforestry Planning, Laurence H. Reeves

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Agroforestry as a sustainable production system has been recognized as a land use system with the potential to slow encroachment of agriculture onto forested lands in developing countries. However, the acceptance of nontraditional agroforestry systems has been hampered in some areas due to the risk-averse nature of rural agriculturalists. By explicitly recognizing risk in agroforestry planning, a wider acceptance of agroforestry is possible. This thesis consists of a collection of three papers that explore the potential of modern stock portfolio theory to reduce financial risk in agroforestry planning.

The first paper presents a theoretical framework that incorporates modern stock portfolio …

Biological Detoxification Of Mercury Contaminated Soil, Shiying Zhang

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined biological mercury removal from soil using mercury-resistant bacteria in soil microcosms. Mercuric chloride was used to artificially contaminate Kidman soil to mercury concentrations of 5 ppm and 10 ppm. Soil moisture content was maintained at three levels, 20%, 30% and 50%. Mercury resistant-bacteria were added to soil samples and the mercury removal rate was compared to control samples without added bacteria. Mercury removal rate was initially enhanced by the addition of bacteria. After 30 days, no difference was observed between samples and controls with initial mercury concentration of 5 ppm when soil moisture content was 20%. At …

The Effect Of Seasonal Cattle Grazing On California Bighorn Sheep Habitat Use, Melanie J. Steinkamp

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of seasonal cattle grazing on a newly reintroduced population of California bighorn sheep (Ovis canadensis californiana) in Big Cottonwood Canyon, Idaho, was studied. The hypothesis that bighorn sheep avoid cattle was tested. The issue of avoidance between bighorn sheep and livestock is arguable. Some studies have found that bighorn sheep avoid cattle while others have found no response of bighorn sheep to cattle.

Evidence was found to document the avoidance of cattle by bighorn sheep. The size of the bighorn's home range and core area decreased with the movement of cattle into areas of high bighorn …

The Feasibility Of Concurrent Enrollment Of High School Students In College-Level Introductory Plant Science, Gregory H. Egan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to test the feasibility of allowing concurrent enrollment in the College of Agriculture to selected high schools in the state of Utah. "Introduction to Agricultural Plant Science" (Plant Science 100) was the course being tested. A purposive sampling technique was used to identify four vocational agriculture programs to participate. There were 86 high school students in the study and 38 college students who took the course on campus at Utah State University.

In this study, 47.7% of the high school students passed the course with a 70% average or above. Comparisons between high school …

Effects Of Exchange Rate Changes On Sugar And Rice Trade Of The Dominican Republic, Gertrudys Brito

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The present research measures the role of exchange rate changes in explaining variations of sugar and rice trade. As background for this research, monetary, fiscal, and exchange rate policies of the Dominican Republic since 1970 are reviewed.

The theoretical framework describing the relationship between exchange rate changes and sugar and rice trade has been tested empirically using the Dominican Republic's annual data for the period of 1970-1987. Regression analyses on the import of rice and export of sugar are estimated.

The regression results conform with the expectation that exchange rate variance is most influential for rice import demand and less …

Production Of Monoclonal Antibodies Specific For The Gamonts Of Eimeria Tenella, Nancy Carol Larsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Cecal coccidiosis, caused by the protozoan Eimeria tenella, may manifest as a devastating disease in young chickens and result in substantial economic loss for producers. The parasite progresses through a complex life cycle, exhibiting both asexual and sexual (gamont) stages of development. The purpose of this study was to produce a panel of monoclonal antibodies (MoAbs) against epitopes contained on surface antigens (Ags) of the gamonts of E. tenella with the intent of blocking the fertilization process. Gamonts were harvested from infected ceca, partially purified by differential centrifugation throught a discontinuous 5050% Percoll density gradient and used as a …

Alfalfa Weevil, Hypera Postica (Gyllenhal), (Coleoptera: Curculionidae) Response To Environmental Factors In Alfalfa Fields In Northern Utah, Larry Edward Jech

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Economic damage to forage alfalfa by the alfalfa weevil occurs frequently enough in northern Utah to warrant applications of an insecticide in some years but not all. Currently a five to ten day period is available to recognize injurious populations then make applications.

Sticky boards, pitfall traps, Berlese funnels sweep samples, stem bouquets, climatic variation and marking techniques were evaluated for alfalfa weevil population predictions. The prevailing climate was the most important factor controlling early adult activities. Early adult feeding and sexual development was the key to forecasting later larval populations. Regional surveys were not adequate for local control recommendations. …

Benefit/Cost Variables And Comparative Recreation Use Patterns Of Wilderness And Non-Wilderness Areas, Kim S. Christy

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This paper examines formal wilderness designation and is presented in two parts. The first section offers a general classification and comprehensive review of the benefit and cost variables associated with wilderness designation and management. The second section investigates recreation use, which society has historically perceived to be the highest valued element in the network of wilderness benefits.

Variables associated with the benefits of wilderness designation are presented under three major categories: 1) naturalness preservation, 2) solitude or primitive and unconfined types of recreation, and 3) special features of scientific, educational, scenic, or historic value.

Costs attributed to wilderness designation are …

The Feasibility Of Artificial Insemination Of Dairy Cattle Managed By Fulani Tribesmen In Kaduna State, Nigeria, Christian Olafimihan Ojomo

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study sought to determine: (a) the essential elements of a viable artificial insemination program for the Fulani Tribesmen in Kaduna State, Nigeria, and (b) to determine if the essential elements of a viable artificial insemination program exist in Kaduna State, Nigeria.

This study was conducted from April 15 to May 15, 1985, in the Artificial Insemination (AI) Subcenters of Zaria, Katsina, Kabomo, Kaduna, Ikara, Zonkwa, Kurmin-Biri, and Kauranjuli.

The data presented in this study were collected by personal interviews with Fulani Tribesmen. The population of this study was from a partial list of Fulani Tribesmen who have had AI …

The Effect Of Utah Population Growth On Conversion Of Agricultural Land To Residential Land, Suzanne Shoshana Dyner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Land resources are essential to the production of many goods and services, including food, fiber, housing, and recreation. Often, these alternate uses are thought to be incompatible, and the conventional wisdom holds that in a place such as Utah, where rapid population growth is occurring near farming activities, at least some agricultural land must be converted to developed uses. The purpose of this paper is to investigate the strength of the relationship between population growth and change in farmland, especially cropland, in Utah.

Theoretically, population growth has been assumed to affect the amount of land in agricultural use. An empirical …

An Economic Analysis Of Food Policy In The Ivory Coast, Yao Prao Felix

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Ivory Coast covers an area of 124,000 square miles with reasonable rainfall for food crops production. But besides what has been called the economic "miracle," the country relies on increasing food imports (rice, wheat, meat, and milk products). At the same time, the country's earnings from the major export commodities are shrinking. So the primary objective was to identify the main causes and circumstances that have resulted in reductions in food production. The major hypothesis was that the present situation is simply the result of policies that have favored cash crops relative to good products. A formal treatment and an …

Alfalfa Production As Related To Irrigation Scheduling: An Economic Perspective, Craig L. Israelsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study analyzed the economics of irrigation scheduling for alfalfa hay in the Cache Valley, Utah area. Yield, evapotranspiration (ET) and irrigation drainage loss, along with the costs and returns per acre attributable to irrigation scheduling, were simulated through the use of a computerized plant growth model. The model created yearly "irrigation schedules" for alfalfa hay based on actual climatic, soil and plant characteristic data from the Utah State University Greenville Experiment Station. The model calculated the irrigation schedules based on a soil-water balance equation which never allowed the available soil water to go below the crop stress point.

The …

Locoweed Poisoning In Cattle: An Overview Of The Economic Problems Associated With Grazing These Ranges, John E. Barnard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Locoweed poisoning, caused by ingestion of certain species of Astragalous and Oxytropis, has had serious economic impacts through a loss of productivity in livestock. This study has attempted to evaluate losses suffered by livestockmen grazing their cattle on areas infested with locoweed species. The results indicate a serious economic impact on these individuals.

Personal interviews were carried out with five cattle ranchers faced with typical locoweed problems. These beef cattle operations were located in Utah, Wyoming, and New Mexico. All of these producers described similar problems and losses due to locoweed poisoning. Information obtained from these interviews was used …

A Linear Programming Analysis Of Several Determinants Of Profit On A Simulated Northern Utah Dairy Farm, Jay Dee Atwood

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the study was to analyze several determinants of profit on a simulated northern Utah dairy farm. A linear programming model was developed to accomplish this. Optimal conditions on the farm were estimated and then other model applications were made to evaluate the importance of milk price, cropland ownership, and corn silage production and feeding. The significance of cow quality also was estimated.

Optimal conditions on the farm gave rates of return to capital between savings rates and loan rates obtainable at a financial institution. Marginal values derived for land did not support the current asking price of …

The Economic Impact Of Potential Changes In Federal Grazing Policies On Ranchers In Wayne County, Utah, Kib Elden Jacobson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to select an area in Utah that was predominantly livestock oriented which used federal lands for livestock grazing, and to develop model ranches exemplifying the typical live-stock operation in the area. These model ranches were then used in a Budget Generator Program (BG) and a Linear Programming framework (LP) to simulate reductions of 25%, 50%, 75% and 100% reductions of BLM land usage. The results were then used to determine income changes, herd size changes, and resource usage in the models as the reductions took place.

The area chosen was Wayne County, Utah because …

An Interregional Study Of Kenya's Livestock Sector Using Linear Programming, Zakayo Joseph Mwangi

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The major purpose of this study was to determine the least-cost method of producing red meat in Kenya. Linear programming was used in the study. A simulated reduction of grazing land available in one of the settlement areas was carried out to indicate what effect this had on the overall regional production pattern of meat in the country.

Kenya was divided into eleven livestock producing and consuming regions. 1979 was used as the base year, and the demand projection was based on the 1979 population. Input and output coefficients, livestock unit requirements, and market prices were developed. A linear programming …

Natural Pastures Of The Macquarie Region Of New South Wales: Their Origin, Composition And Management, David Leslie Michaelk

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Two experiments were conducted in the semi-arid (400 millimeter annual rainfall) Macquarie region of New South Wales, Australia, at the Trangie Agricultural Research Station (31° 59'S; 147° S7'E), to examine (a) the way botanical parameters can be used to separate grazing and climatic impacts on range vegetation, and (b) how this delineation affects application of range science tenets (site, condition and trend) to different pasture types.

Two range sites were studied: Site 1, a light soil type, was dominated by annual grasses, legumes and forbs, whereas perennial grasses (mainly Chloris acieularis and Chloris truncata) dominated the heavy soils of …

An Economic Analysis Of The Akkar Plain Project, E. Douglas Chard

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this paper is to determine the economic feasibility of the Akkar Plain Agricultural Development Project. Data were collected at representative villages throughout the Akkar Plain in Syria. The data were used to establish the economic setting at the present time on the Akkar Plain and to establish a basis for determining the economic justification for the future planned developments. Methodology used was a farm budget analysis of a before development and after development situation. Internal rate of return and benefit/cost ratio were the measures used to determine economic feasibility. The paper discusses previous work completed, the development …

An Economic Analysis Of Farm Flock Sheep Production In Utah, Ken Beck

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to evaluate the economic aspects of farm flock sheep production in Utah. Using 1979 as a base year, costs and returns were calculated from data obtained from twenty- six Utah farms. Characteristics that typify the states· farm flock sheep production, at this writing, with regard to: 1) the farm flock producers and 2) the farm flock enterprise, were presented.

Various models were dev eloped and examined using Multiple Regression and Linear Programming analytical techniques. Multiple Regression was us ed to estimate the effects that different variables had on the profitability of the sheep enterprise. …

Location Value Of Milk, Martin K. Beutler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to the growth of milk marketing areas in the Intermountain West, a study was made to determine the most advantageous allocation of producer milk to twelve selected processing demand areas and to calculate location differentials between these same markets. A theoretical determination of location differentials and of the allocation of milk supply areas to processing centers were made using supply-push and demand-pull price alignment models developed by Associated Milk Producers, Inc., for the months of November 1979 and June 1980. Grade A producer mil k from the six member cooperatives of Western Dairymen' s Cooperative, Inc., was used in …

Job Competencies, Employment Demands, And Perceived Training Needs In Production Agriculture In Utah, James O. Summers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was limited to 165 farmers involved in various segments of production agriculture in the state of Utah. County agents and vocational agriculture teachers in each county nominated these farmers as candidates according to their respective farming operations.

The following six defined areas of production agriculture were used as selection criteria to insure equal input in the study: Beef, Dairy, Swine, Sheep, Poultry, and Crops. All farmers were surveyed by means of persona l interviews conducted by either county agents or vocational agriculture instructors in their respective counties. The surveying instrument used was developed through a thorough review of …

Economic Impacts Of Public Grazing Reductions In The Livestock Industry With Emphasis On Utah, Deevon Bailey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this paper was to determine the immediate impact of reductions in public grazing on livestock production in the United States. This was accomplished by the use of linear programming techniques. Different grazing reduction simulations were utilized to determine the short and long run effects of across-the-board reductions in public grazing.

The United States was divided into 13 regions. The 11 western states were considered as individual regions. Special emphasis was placed on the effects of grazing reduction on Utah. The availability and utilization of feed and livestock products during a "normal year", 1978, were considered in this …

Competencies Needed For Careers In Ornamental Horticulture In Utah, Dennis George Bahen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of the study was to present descriptive data bout the industry, determine the importance of the competencies needed for job entry, and assess the manpower needs of the ornamental horticulture industry in Utah.

The identified population of 576 ornamental horticulture enterprises was categorized into seven areas of specialization: Arborists (4.5%), Maintenance of Landscapes (10.8%), Landscape Construction (18.6%), Golf Courses (13.5%), Greenhouse Production (5.4%), Florist-Plant Shops (30.9%) and Garden Center-Nurseries (16.3%).

The data were collected by a survey-questionnaire. One hundred and sixteen ornamental horticulture enterprises responded to the survey. This amounted to 38% of the industry sampled and 20% …