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Influence Of Angler Motivations, Expectations, And Opinions On Fishery Management Practices In The United States, James E. Brogdon May 1977

Influence Of Angler Motivations, Expectations, And Opinions On Fishery Management Practices In The United States, James E. Brogdon

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This report is concerned with the behavioral inputs into the decisions concerning fishery resource management. Topics discussed are motives, expectations, and opinions of fishermen concerning the fishing experience and present-day fishery management practices and regulations; how management agencies and sportsmen organizations have dealt with recreational fishing; the need for managers to utilize this behavioral information in forming management decisions; and where past people-wildlife research has been and where it must lead in the future. Material for this paper came from copies of published articles and library research.


A Manpower Study Of The Utah Feed, Grain, And Seed Industry And The Idaho Seed Industry, Earl Ray Thomsen May 1977

A Manpower Study Of The Utah Feed, Grain, And Seed Industry And The Idaho Seed Industry, Earl Ray Thomsen

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

As the farmers of Utah and the nation become more highly trained and more efficient in adapting new technological knowledge in their farming enterprises, farms increase in size and the number of workers needed to produce food for our state and nation decreases. A concurrent yet opposite change occurs in those businesses which perform services for farmers or which market, process, and distribute the farmer's product. Farmers are demanding more skilled services while consumers are demanding that the farms' products receive more processing and distribution services which must be performed off the farm. We, thus, have a growing network of …


Rodent Density And Species Composition In The Snake River Birds Of Prey Natural Area, Idaho, Jon R. Montan Jr. May 1977

Rodent Density And Species Composition In The Snake River Birds Of Prey Natural Area, Idaho, Jon R. Montan Jr.

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rodent densities were estimated in the major vegetation types of the Snake River Birds of Prey Natural Area in 1975 and 1976 by a combination of live-trapping and kill-trapping. Only deer mice (Peromyscus maniculatus) were numerous enough to permit reliable density estimates. Relative densities of other rodent species were indicated by kill-trap capture rates. Densities of deer mice correlated well (r = 0.99) with kill-trap capture rates. The use of kill-trapping in place of live-trapping in 1976 permitted extensive sampling throughout the 1930 km2 study area. Differences were found among the major vegetation and land-use types in …


Competitive Interaction In Plant Populations Exposed To Enhanced Uv-B Radiation, Fred M. Fox May 1977

Competitive Interaction In Plant Populations Exposed To Enhanced Uv-B Radiation, Fred M. Fox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Competitive balance and changes in individual plant growth parameters of eight pairs of plant species exposed to enhanced UV-B irradiation were determined under field conditions simulating ozone reductions of about 0.08 atm·cm. The levels of irradiance represented ozone decreases of about 25-30 percent from approximate ambient ozone concentrations for high solar altitudes on clear days during the study. A method for calculating and statistically analyzing relative crowding coefficients was developed and used to evaluate the competitive status of the species pairs sown in a modified replacement series. The effect of UV-B irradiance was generally detrimental to plant growth, and was …


Seasonal Course Of Root Respiration In Atriplex Confertifolia, Richard S. Holthausen May 1977

Seasonal Course Of Root Respiration In Atriplex Confertifolia, Richard S. Holthausen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Root respiratory response of mature Atriplex confertifolia plants growing in established communities was measured during two growing seasons using freshly excised root segments and gas chromatography techniques. Respiratory response at fixed test temperatures changed significantly during the growing season, and this pattern of respiratory adjustment varied for root segments located at different depths in the soil profile. Respiration measured at a constant test temperature was highest during early sumner, and declined to minimum values in late summer and fall. Root segments taken from the top 30 cm of the soil profile displayed peak activity several weeks before root segments from …


The Effect Of Four Mine Spoil Treatments On The Seedling Water Relations Of Two Plant Species, Lorraine K. Van Kekerix May 1977

The Effect Of Four Mine Spoil Treatments On The Seedling Water Relations Of Two Plant Species, Lorraine K. Van Kekerix

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Surface mines in mountainous areas cause environmental deterioration at lower elevations in the watershed. The most successful long term solution to the downstream problem is revegetation. However, mine spoils are low in essential plant nutrients, have low water holding capacity, and are often acidic. These factors limit plant colonization. Plants must also be adapted to the environmental conditions of high elevations.

At the McLaren Mine, }1ontana, at 2800 m, it was observed that seedlings on revegetation plots were desiccated, indicating possible water deficits. Field and growth chamber studies were carried out to determine the effects of some spoil ameliorating treatments …


Biological Manipulation Of Blackbrush (Coleogyne Ramosissima Torr.) By Browsing With Goats, Frederick D. Provenza May 1977

Biological Manipulation Of Blackbrush (Coleogyne Ramosissima Torr.) By Browsing With Goats, Frederick D. Provenza

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to provide data on responses of Angora goats and blackbrush (Coleogyne ramosissima) to a biological manipulation program. Blackbrush utilization levels averaged 30, 16, and 6 percent (545, 367, and 147 kg per hectare) for the heavily, moderately, and lightly browsed pastures, respectively; removal rates of 77, 38, and 19 percent (1164, 582, and 291 kg per hectare) were projected.

Statistically significant differences in body weight loss (P=0.052) were noted for goats browsing in different replications. Goats lost an average of 14 and 19 percent of body weight in replications one and two, …


Resource Partitioning In The North American Gallinules In Southern Texas, William W. Reagan May 1977

Resource Partitioning In The North American Gallinules In Southern Texas, William W. Reagan

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Data on the Common and Purple Gallinules at the Welder Wildlife Foundation in South Texas indicated that resource partitioning between the two birds occurred. The objectives of this study were: (1) to compare differences in daily activities; (2) to investigate nesting habits; and (3) to measure physical characteristics of the two birds.

Three methods of resource partitioning were utilized by the two gallinules. (1) Common Gallinules selected open water associated with sparse panicum and paspalum grasses while Purple Gallinules selected dense panicum and paspalum grasses. (2) Common Gallinules during migration and throughout the season shifted gradually from a sparse panicum …


Aspects Of The Life History Of Three Catostomids Native To The Upper Colorado River Basin, Charles W. Mcada May 1977

Aspects Of The Life History Of Three Catostomids Native To The Upper Colorado River Basin, Charles W. Mcada

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The distribution, abundance and life history were studied for three catostomids -- the razorback sucker (Xyrauchen texanus), the flannel-mouth sucker (Catostomus latipinnis), and the bluehead sucker (Catostomus discobolus) -- all native to the upper Colorado River basin. The razorback sucker has declined in abundance due to man's impact upon the system and it has been recommended that this species be listed as ''threatened" on the U. S. Department of the Interior's list of Threatened or Endangered species [Personal corrmunication, G. C. Kobetich, U. S. Fish and Wildlife Service, Las Vegas, Nevada]. During this investigation, …


In Vitro Morphogenesis And Mutation Of Glycine Max L., Thomas Daniel Wilson May 1977

In Vitro Morphogenesis And Mutation Of Glycine Max L., Thomas Daniel Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Soybean (Glycine max L. c.v. Consoy) tissue cultures were grown in synthetic media containing various concentrations and combinations of minerals, auxins, cytokinins, pH levels, and inorganic growth factors in a systematic procedure to establish optimum media for initiation and maintenance of callus. Further modification of the hormone level was employed to initiate callus morphogenesis. Normally toxic levels of atrazine were established in soybean calli media, and ethyl methanesulfonate (EMS) and X ray-induced mutant calli were selected for atrazine tolerance.

Optimal media for initiation and maintenance of soybean calli were developed and a defined medium was determined that consistently yields …


Genetic Control Of Spermiogenesis In Drosophila Melanogaster: The Effects Of Abnormal Association Of Centrosome And Nucleus In Mutant Ms(1)6s, Douglas Lee Habliston May 1977

Genetic Control Of Spermiogenesis In Drosophila Melanogaster: The Effects Of Abnormal Association Of Centrosome And Nucleus In Mutant Ms(1)6s, Douglas Lee Habliston

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Mutant ms(l)6S of Drosophila melanogaster is characterized by a spectrum of abnormalities of spermatid differentiation. Included in these are failure of the basal body to make normal attachment to the nucleus, failure of acrosomes to develop, and lack of a normal pupulation of perinuclear microtubules. There is also a failure of normal chromatin condensation and nuclear elongation. The mitochondria do not form a normaI nebenkern, but nevertheless fuse, elongate, and develop paracrystalline bodies. The number of normal axonemes is markedly reduced as a result of the failure of some centrioles to form basal bodies. All of these aberrations can be …


A Preliminary Investigation Of The Lipid Of Halophilic Bacteria As A Food Additive, Neil F. Collins May 1977

A Preliminary Investigation Of The Lipid Of Halophilic Bacteria As A Food Additive, Neil F. Collins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study was conducted to evaluate the feasibility of obtaining workable quantities of the unusual ether-linked phosphatidyl glycerophosphate of halophilic bacteria through batch culture of Halobacterium halobium. Once isolated and purified, physical, emulsification, and toxicological properties of the lipid were evaluated with respect to its use as a nonnutritive lipid substitute or an emulsifier by the food industry. These evaluations included physical descriptions, melting properties, hydrophile-lipophile balance (HLB) determination, and oral and intraperitoneal administration of the lipid to laboratory mice.


Fine Structural Aspects Of The Developing Eye Of The Honey Bee, Judith Susan Eisen May 1977

Fine Structural Aspects Of The Developing Eye Of The Honey Bee, Judith Susan Eisen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The post-embryonic development of the compound eye of the worker honey bee was investigated with the light and electron microscopes. The cells of the optic primordium were reorganized into preommatidial cell clusters during the late third and early fourth larval instars. Each cluster contained nine prospective retinula cells, the ninth was centrally located and shorter than the other eight; four prospective cone cells; and an undetennined number of prospective pigment cells.

Rhabdomere development began in the eight peripherally located retinula cells just prior to pupation. Following pupation, each ommatidium elongated. During ommatidial elongation, the short ninth retinula cell moved from …


Importance Of Legumes, Especially The Trifolium Species, In Range Improvement, Abdelhai A. Ibnattya May 1977

Importance Of Legumes, Especially The Trifolium Species, In Range Improvement, Abdelhai A. Ibnattya

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This paper analyzes the most important characteristics of legumes, which have led to their utilization in range improvement all over the world. It emphasizes the Trifolium spp. (esteemed among the legume family), their contributions to soil a n d forage improvement, and the success obtained from their utilization, especially in semi-arid ranges. Many references originally from Australia, United States, Morocco, and Portugal were used as sources of data because of the ample utilization of these species in these countries. Careful analysis related to requirements, potentialities, and production of clovers were used and recommendations were made for different ecological areas where …


Influence Of Corynebacterium Insidiosum On The Water Relations Of Alfalfa, Rastri Dey May 1977

Influence Of Corynebacterium Insidiosum On The Water Relations Of Alfalfa, Rastri Dey

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The effect of Corynebacterium insidiosum (McCull) H. L. Jensen on the water relations of its host, alfalfa, was studied by field measurements made on a 6-year-old stand of Ranger alfalfa. Periodic measurements of stomatal conductance, xylem pressure potential Ψ, and root, stem, and leaf conductance were made in relation to soil moisture conditions. Water regain and electrolyte leakage studies were also made to test membrane integrity in diseased plant leaves.

At all times the xylem pressure potential Ψ was found to be much more negative in diseased plants than in healthy plants. Stomatal conductance was found to respond to the …


Seed And Cone Insects Associated With Pinus Monophylla Torr. And Frem., Michael James Jenkins May 1977

Seed And Cone Insects Associated With Pinus Monophylla Torr. And Frem., Michael James Jenkins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Dissection and rearing studies of second-year cones disclosed six species of insects associated with the seeds and cones of singleleaf pinyon pine. Those most commonly encountered were: Dioryctria sp. probably albovittella Hulst, Conophthorus monophyllae Hopkins and Pineus coloradensis Gillette. The three remaining species were of lesser importance. These included the gall midge, Asynapta sp., a minor cone pest and two parasites, one of C. monophyllae, Acerocephala atroviolacea Crawford and an unidentified parasite of Dioryctria, of the family Ichneumonidae.

D. sp. probably albovittella was regarded as the major insect destroying cones and seeds of P. monophylla in …


A Comparison Of Dewpoint And Psychrometric Mode In Leaf Water Potential Measurements, Gladys Durand-Campero May 1977

A Comparison Of Dewpoint And Psychrometric Mode In Leaf Water Potential Measurements, Gladys Durand-Campero

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaf water potential of two maize plants (Zea mays L.) two chlorophytum plants (Chlorophytwn capense, Kuntze), a schefflera (Brassaia actinophylla) and one aspen (Populus tremuloides Michx.), were measured under laboratory conditions with aluminum block in situ leaf hygrometers and with stainless steel single junction chamber hygrometer using excised entire leaves. Plants were subjected to a drying cycle. The hygrometers were controlled with a dewpoint microvoltmeter and all readouts were recorded on a chart recorder. A typical reading and control schedule included 20 second cooling before a first psychrometric reading allowing the output to …


Coyote Movement Patterns With Emphasis On Home Range Characteristics, Stephen J. Hibler May 1977

Coyote Movement Patterns With Emphasis On Home Range Characteristics, Stephen J. Hibler

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Standard radio telemetry techniques via triangulation were used to determine coyote locations and to construct maps of coyote movement patterns in Curlew Valley (Utah and Idaho). Home range sizes were determined by establishing corresponding boundaries drawn on the basis of location, density and relative number of visitations (contour method), and then tracing the boundaries with a compensating polar planimeter. Mean home range sizes were determined directly for only those animals with home range values that reached an asymptote when plotted against corresponding time periods. This asymptotic value was considered the best estimate of the actual home range size. Four adult …


Identification Of Products Arising From The Metabolism Of Cis-And Trans-Chlordane By Rat Liver Microsomes In Vitro: Outline Of A Possible Metabolic Pathway, Alan Arthur Brimfield May 1977

Identification Of Products Arising From The Metabolism Of Cis-And Trans-Chlordane By Rat Liver Microsomes In Vitro: Outline Of A Possible Metabolic Pathway, Alan Arthur Brimfield

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The metabolism of pure cis- and trans- chlordane was studied in vitro. Microsomal preparations from the livers of male rats induced with cis- or trans-chlordane in feed for ten days were used to metabolize the pure compound corresponding to the inducer. Subsequent extraction, column fractionation and combined gas chromatography-mass spectroscopy resulted in the characterization of four compounds not previously reported from an in vitro system.

In addition to the substrate, trans-chlordane extracts contained species with the following molecular weights and empirical formulae: m/e 370, C10 H5 Cl7 , heptachlor; m/e 352, C10 H6 OCl …


Increased Calf Production And Returns From Improved Range And Livestock Management On A Northern Utah Ranch, Michael H. Ralphs May 1977

Increased Calf Production And Returns From Improved Range And Livestock Management On A Northern Utah Ranch, Michael H. Ralphs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The operating costs for farms and ranches in the United States have increased 81 percent between 1970 and 1976. Calf prices over this same period have fluctuated dramatically and have fallen from a high of $58/cwt in 1973 to a low of $26/cwt in 1975. Since 1973, the increasing operating costs have exceeded the returns gene rated by the low calf prices and have left operators in a negative financial position. This case study has shown that the operator has increased both the scale and efficiency of his operation through improved lives tock husbandry and range improvements, yet has been …


An Evaluation Of Using In-Field Evaporation Pans To Schedule Irrigation On Potatoes, Michael J. Tremblay May 1977

An Evaluation Of Using In-Field Evaporation Pans To Schedule Irrigation On Potatoes, Michael J. Tremblay

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research project was undertaken to determine if an evaporation pan would accurately predict evapotranspiration when placed in an actual irrigated field situation. Two potato fields in Southern Idaho with different micro-climates and soil types were used in this study. The in-field evaporation pan method was compared with the gravimetric method and the Jensen-Haise and modified-Penman climatic methods. Yield and quality responses were evaluated by varying the amount of sprinkler-applied water so that three distinct moisture regimes were evaluated. It was also necessary to evaluate recent crop coefficient (Kc) curves on potatoes to see if the Kc …


Toxicological And Biochemical Investigations Of Alpha-Chaconine In Potato (Solanum Tuberosum L. ) Tubers: Physiologic Disposition And Tissue Binding, And Inhibition Of Tissue Cholinesterases And Isoenzymes, Sydney Obodoechina Alozie May 1977

Toxicological And Biochemical Investigations Of Alpha-Chaconine In Potato (Solanum Tuberosum L. ) Tubers: Physiologic Disposition And Tissue Binding, And Inhibition Of Tissue Cholinesterases And Isoenzymes, Sydney Obodoechina Alozie

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The distribution, absorption, metabolism and tissue binding of radioactivity were studied in hamsters after oral and intraperitoneal administration of alpha-chaconine- (3H). The material was well absorbed from the gastrointestinal tract and nearly 22 percent of the label was excreted via urine and feces in 7 days. The excretion was higher in urine (21 percent) than in feces ( < 1 percent). Tissue concentrations of radioactivity peaked at 12 hours following oral administration, with the highest concentrations found in lungs, liver, spleen, skeletal muscle, kidney and pancreas, with heart and brain containing moderate amounts. Concentrations of radioactivity in tissues following intraperitoneal administration were significantly higher than those observed after oral treatment. Excretion of chloroform-soluble products in the feces was 10 times higher than that of the chloroform-insoluble metabolites after both oral and intraperitoneal administration. In the urine, the activity was predominantly in the chloroform-insoluble form and the chloroform-soluble metabolites were relatively minor in amounts (0.27, 0.85, and 2.45 percent versus 0.005, 0.14 and 0.19 percent of dose for 12, 24 and 72 hours, respectively). After 7 days, the chloroform-soluble metabolites in urine increased to 20 percent of the excreted radioactivity, while the amount of chloroform-insoluble metabolites was less than 1 percent. Subcellular distribution of the labeled compound indicated the highest concentration of radioactivity in the nuclear and microsomal fractions of brain, liver and heart tissues. A small amount of radioactivity, shown by a minor peak, was also observed in the fractions between the mitochondrial and microsomal fractions on a sucrose gradient. Binding of radioactivity was observed in brain, testes, kidney, lung, liver and heart. All of the label in the brain appeared to be in the bound form. The results indicated that alpha-chaconine is slowly absorbed from the gastrointestinal tract after oral administration, and persists in various tissues, much of it in bound (non-extractable) form (in nuclear and microsomal fractions).

Excretion of alpha-chaconine- (3H) and its metabolites was investigated after oral and intraperitoneal administration in hamsters. The separation of the glycoalkaloid and its metabolites in feces and urine was accomplished by thin-layer chromatography. An increase in the concentration of excreted …


Infrared Imagery Scanning Systems For Censusing Big Game, Peter S. Goldberg May 1977

Infrared Imagery Scanning Systems For Censusing Big Game, Peter S. Goldberg

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The primary objective of this study was to explore the potential of an airborne infrared scanner for the census of mule deer (Odocoileus hemionus) and elk (Cervus canadensis) in the Intermountain West. Flight altitude was varied in hopes of achieving species separation, and ground studies were conducted, using a hand-held radiometer and captive deer, to find the optimum time of morning to census. The problems and potentialities of infrared imagery scanning systems for censusing big game are discussed and compared to visual aerial census methods.


Sheep Behavior And Vulnerability To Coyote Predation, Ernest Albert Gluesing May 1977

Sheep Behavior And Vulnerability To Coyote Predation, Ernest Albert Gluesing

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the activity patterns and social relation ships between individuals in a large herd of domestic sheep (Ovis aries) in an effort to determine if behavioral characteristics predisposed certain individuals to coyote (Canis latrans) predation.

The research was conducted on the Cook Ranch near Florence, Montana, from March through September of 1975. Data were collected from a herd of 627 ewes and 1082 lambs, each individually identifiable. A random sample of 44 ewes and their 75 lambs were intensively studied over a 16-wk period to establish activity budgets and the relationships between sheep activity …


A Study Of Rest Period, Hardiness, And Bud Development Of The 'Concord' Grape, Mervin Gayle Weeks May 1977

A Study Of Rest Period, Hardiness, And Bud Development Of The 'Concord' Grape, Mervin Gayle Weeks

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The length of the 'Concord' grape rest period was evaluated during 1974-75 and 1975-76. Cuttings were placed in a 25 C growth chamber every two weeks from October through April. Number of days to reach 50 percent full bud swell was plotted to determine rest completion. Seven years of weather data and full bloom dates of 'Concord' grapes from Prosser, Washington were statistically analyzed to give another estimate of rest completion. Rest was terminated after about 830 chill units.

During 1974-75 and 1975-76, T50 temperatures were determined every two weeks for both cambium and primary buds of 'Concord' grapes. …


Consumption, Digestion, And Utilization By Goats Of The Dry Matter And Nitrogen In Diets Containing Oak (Quercus Gambelii) Foliage, Anastasios Stefanos Nastis May 1977

Consumption, Digestion, And Utilization By Goats Of The Dry Matter And Nitrogen In Diets Containing Oak (Quercus Gambelii) Foliage, Anastasios Stefanos Nastis

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Part I
A study of animal performance was made with goats fed, ad libitum ground and pe11eted mixtures of Gambe1 oak and alfalfa. Intake, digestibility, metabolizable nitrogen, and metabolized energy of oak diets were generally lower than those for a control alfalfa diet. However, no significant differences in live weight gains of experimental animals were found. No apparent toxicity was detected in goats fed diets containing up to 80 percent oak for 72 days.

Part II
Mixtures of oak (Quercus gambelii) and alfalfa (Medicago sativa) were used to evaluate three laboratory techniques, the Tilley and Terry …


Persistence Of Mucor Miehei Protease In Cheddar Cheese And Pasteurized Whey And Its Effect On Sterile Milk Products, Randall Kirk Thunell May 1977

Persistence Of Mucor Miehei Protease In Cheddar Cheese And Pasteurized Whey And Its Effect On Sterile Milk Products, Randall Kirk Thunell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Whey from a commercial cheese plant, taken at draining on five separate days, from cheese made with a Mucor miehei coagulant was cooled within 1 h to 4 C. Portions were adjusted from pH 4.2 to 6.4 at .2 pH intervals and subjected to HTST pasteurization at 73.9, 76.6, and 79.5 C for 25 sec. Milk clotting activity in whey was determined before and after pasteurization. Resistance to heat in-activation increased with decreasing pH. All measurable activity was destroyed above pH 5.4 by pasteurization at 79.5 C, above pH 5.8 at 76.6 C and above pH 6.0 at 73.9 C. …


Autoecology Of The Ruderal Weed Heterotheca Grandiflora With Emphasis On Germination Dimorphism, Stephan Dexter Flint May 1977

Autoecology Of The Ruderal Weed Heterotheca Grandiflora With Emphasis On Germination Dimorphism, Stephan Dexter Flint

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Weedy species, as they occupy diverse and unpredictable environments, are expected to possess considerable variability in numerous characteristics, including germination. The visually dimorphic achenes of Heterotheca grandiflora Nutt. (Asteraceae) were tested for potentially adaptive differences in their germination, the establishment of the resulting seedlings, and the relative production of the two achene types.

Achenes produced by the disc florets are adapted for dispersal and rapid germination while the ray florets produce smaller achenes lacking a dispersal mechanism, but possessing a more sophisticated physiological system capable of regulating germination. Ray achene germination rates were significantly influenced by different soil surfaces while …


The Effects Of Campgrounds On Small Mammals In Canyonlands And Arches National Parks, Utah, Gregory A. Clevenger May 1977

The Effects Of Campgrounds On Small Mammals In Canyonlands And Arches National Parks, Utah, Gregory A. Clevenger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Campground use in our national parks is increasing yearly, but little quantitative data are available concerning the impact this use is having on the ecology of the campground and surrounding area. This paper reports on some of the effects of campgrounds on small mammal populations in Canyonlands and Arches National Parks, Utah. Data collection consisted of live-trapping from April to November, 1975 (12,337 trap-nights). The populations of Ordls kangaroo rat (Dipodomys ordii), antelope ground squirrels (Ammospermophilus leucurus), deer mice (Peromyscus spp.), woodrats (Neotoma spp.), Colorado chipmunks (Eutamias guadrivittatus), and desert …


Diet Composition And Activities Of Elk On Different Habitat Segments In The Lodgepole Pine Type, Uinta Mountains, Utah, William B. Collins May 1977

Diet Composition And Activities Of Elk On Different Habitat Segments In The Lodgepole Pine Type, Uinta Mountains, Utah, William B. Collins

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The biweekly diets of tame elk (Cervus canadensis nelsoni) were established on a species dry-weight basis for different habitat segments of the lodgepole pine (Pinus contorta) type, Principal species in the diets (5% or more) on each habitat segment were generally composed of preferred species. However, some highly abundant but non-preferred species took on principal dietary status, whereas some preferred species, scarce in the vegetation, contributed less than 5 percent to diets. Forbs contributed most to total consumption; grasses and sedges were the second largest contributors. Browse appeared to be of limited importance, but mushrooms had …