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Factors Contributing To The Conservation Of Phacelia Submutica (Boraginaceae), A Threatened Species In Western Colorado: Reproductive Biology And Seed Ecology, Alicia M. Langton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Conservation and recovery plans for rare species require biological and ecological information to discern how they may be susceptible to human disturbances. Phacelia submutica is a threatened annual species in western Colorado. Human activities including energy development, recreation, and livestock grazing are occurring within the species’ range. To provide conservation practitioners with a scientific basis for management, this research aimed to elucidate elements of the species’ ecology. Chapter 2 describes the reproductive biology of P. submutica. Potential insect pollinators were not observed during two years of observations. Floral traits and development ensure self-pollination and reduce the likelihood that insects …

The Association Of Seed And Cone Predator Populations And Cone Crop Production In Engelmann Spruce, Dawn E. Cameron

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Engelmann spruce (Picea engelmannii Parry ex Engelm.) exhibits cone crop periodicity, producing seed in a cyclic pattern. Variation in seed production has been noted between individuals of a population, but synchronization on a large scale is common. The theory that ultimately these periodic large cone crops have resulted from the selective pressures of seed and cone predators, referred to as the predator satiation hypothesis, is considered. Assuming predator pressures have operated over evolutionary time to select for periodic synchrony, associations between seed and cone predators and cone crop production levels were anticipated. These potential consequences of predator satiation were …

Seed Rain Patterns During Early Recovery On A Strip-Mined Site In Southwestern Wyoming, Hal W. Gordon

Undergraduate Honors Capstone Projects

Revegetating surface-mined soils of the western United States is a major problem facing natural resource managers today. The Surface Mine Reclamation and Conservation Act (SMRCA, Public Law 95-87) requires that the opera tor: "… establish on the regraded areas, and all other lands affected, a diverse, effective and permanent vegetative cover of the same seasonal variety native to the area of land to be affected and capable of self-regeneration and plant succession at least equal in extent of cover to the natural vegetation of the area ... "

Historically, most of the coal produced in the U.S. came from the …

Seed Reserves In Stockpiled Topsoil On A Coal Mine Near Kemmerer, Wyoming, Cynthia K. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The objectives of this study were to determine how seed reserves varied with depth in topsoil stockpiles and to evaluate the effect of length of time of storage on the number of viable seeds and number of species of seeds.

Soil samples were taken from five topsoil piles representing zero to three years of storage on the Elkol-Sorenson mine near Kemmerer in southwestern Wyoming. Seeds were extracted using flotation/separation methods and were tested for viability using 2,3,5-triphenyl tetrazolium chloride solution. Data were analyzed using nonparametric statistical tests.

Overall density of seeds in topsoil piles was low. No relationship was found …

Metaphorical Interpretations Of The Neurotic Paradox, Mark J. Weaver

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This is a theoretical/philosophical paper which is intended to bring to the reader's attention an emerging literature and discussion which holds potentially productive consequences for the understanding of man. This thesis does not offer completed formulations or empirical groundings. The purpose is to create a basis for dialogue.

This paper will initially specify a current conflict in psychology around the different metaphors used to define the image of man. A theoretical/philosophical basis for viewing the process of generating models of man and his behavior as essentially "metaphorical" is then presented. A specific category of human behavior known as the neurotic …

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 …

Seed Response Under Snow On A Subalpine Range In Central Utah, Alvin T. Bleak

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The response of grass, forb, and shrub seeds to the subalpine environment during the fall and under winter snow and under laboratory conditions at 20/28 C was observed for 3 consecutive years at an elevation of about 3000m on the Wasatch Plateau in central Utah.

Seeds in nylon sleeves were planted under 2 cm of soil before snowfall. Under snow plantings were made directly on the soil surface and under 2 cm of soil. The seeds planted before snowfall were removed each year on four occasions: when under snow plantings were made, after snow depth exceeded 130 cm (deep snow), …

Effect Of Gibberellic Acid And Chilling On Nucleic Acids During Germination Of Dormant Peach Seed, Yuh-Nan Lin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study of nucleic acid changes influenced by gibberellic acid and chilling treatments in peach seed was performed in an attempt to reach a better understanding of the mechanism involved in breaking seed dormancy.

Gibberellic acid and the chilling treatment increased the RNA content. These two treatments which break dormancy also increased RNA, suggesting a similar mechanism involving RNA. Chilled seeds contained more RNA than did the gibberellic acid treated seeds.

DNA content remained unchanged regardless of treatment.

Dry seed had a greater ribonuclease activity than with soaked seeds. Enzyme changes did not correlate well with the RNA content in …

The Inhibition Of Germination Caused By The Lemma And Palea On Phalaris Arundinacea Seed, Nard Vee Allen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Reed canarygrass (Phalaris arundinacea) is adapted to low wet lands and survives flooding and periods of drought. Much of the valley bottom land of Utah is flooded during part of the year, yet some of this land is very dry late in the summer. This grass could become an important forage for Utah's valley bottom lands if stand establishment could be assured. Low germination percentages and long germination periods under field conditions often result in poor stands.

In most cases quick uniform germination is a decided advantage in establishing stands. Fall plantings have usually been more successful than …

Seed And Forage Production In Four Clonal Lines Of Alfalfa As Influenced By Lygus Infestation, John Keith Noyes

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

No other forage crop cultivated in the United States can be used in as many ways as alfalfa. The variety of its uses make it a most useful forage crop.

The distribution of alfalfa is world wide and it plays a leading role in the production of livestock and their products. For general feeding of farm animals, alfalfa is unsurpassed. Used for pasture, it has a high capacity, which leads to large gains in grasing animals. If properly rotated and cared for, it adds nitrogen to the soil in a form that is available to plants and thereby increases crop …

Temperature And Atmospheric Humidity As Factors Influencing Seed Setting In Alfalfa, Lealand A. Clark

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For many years seed growers have thought that definite relationships existed between seed production and the weather. When this subject is approached there is little unity of opinion, even among neighboring seed growers. This lack of unity would indicate that growers generally are aware of some cause which affects seed setting, but they are not certain that any particular condition of the weather is the chief contributing factor. Scientific writers¹ on the subject are also confident that weather is probably one of the major factors influencing seed production.

A Study Of The Seasonal History Of Alfalfa Flowers As Related To Seed Production, John W. Carlson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A few researches have been concerned with the structure and pollination of alfalfa flowers. Others have considered the biological problems concerned in the pollination and fecundation of the flowers. In none of these studies, however, has an attempt been made to follow carefully the alfalfa flowers through various stages of development. Nor has any effort been made to determine what effect the condition and duration of these stages may have upon the resulting seed crop.

The work that follows is a study of the changes through which the alfalfa flowers pass during the season while functioning as organs of seed …

The Effect Of Dry Heating On Alfalfa Seed And Adulterants, Ernest V. Staker

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The relationship of artificial heating to the germination of seeds has been a subject of more or less interest for the last 75 years. Like other research work, experimenters first had their attention called to the problem largely as the result of innate curiosity. They were interested in the result as measured by germinative power, of the application to seeds of different amounts of heat for varying periods of time, consequently many divergent and sundry experiments were carried out. Seeds of a large number of plants have been subjected to tests and the results recorded. The investigations include the effect …

Effect Of Root-Rot Upon Sugar-Beet Seed Production, Louis F. Nuffer

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Due to considerable loss through root-rot of mother beets while in storage during the winter of 1918-1919 the Amalgamated Sugar Company asked advice in regard to planting beets which had decay lesions on them. Would the beets yield seed if planted? How much seed would these beets yield as compared with healthy beets? Would the seed produced be injured by having been grown on decayed beets? It was felt that an experiment carried out with the above questions in view would bring out many facts upon which to base conclusions in answering the questions of the Sugar Company.