This study is an attempt to bring together such available material , heretofore not collected, into a single compilation pertaining to the plant associations of Utah and Salt Lake Valleys. An endeavor is made to build a picture of the vegetation as it was before the pioneers entered these valleys as compared with what it is today. The material compiled here is the result of searching through all available sources such as government reports of geological explorations, private diaries of explorers and pioneers , contemporary magazines, books and newspapers .

The ecology of subalpine fir relative to broom rust was investigated. Broom rust infections were most common in trees growing on limestone soils, and seldom occurred on trees growing on basalt soils. Even though plant moisture stress was consistently higher in the plants from limestone soils, the studies indicated that moisture stress is not the major factor causing infection. The amounts of available magnesium and phosphorus were much lower in the limestone soil. It is postulated that the higher plant moisture stress of subalpine fir growing on limestone soils may aggrevate the lack of nutrients and be a contributing factor to the susceptibility of subalpine fir to broom rust. Even though the study raises more questions than it answers, management prescriptions relative to this disease can be proposed. Pruning and burning of diseased branches should be evaluated as a possible method to control broom rust on subalpine fir. This species must be better managed because of its strategic position on watersheds and recreation sites of higher elevations.

The aquatic and semi-aquatic plant communities of Utah Lake, Utah County, Utah are discussed. This discussion includes the methods of describing and delimiting the major vascular plant communities, the descriptions of the present existent communities, and the determination of the vegetational changes, particularly since 1925. The vegetation around Utah Lake is divided into plant communities. Each community is discussed using: (a) quantitative data, (b) field observations, (c) general and specific locations of the community, and (d) interrelationships and trends of the community. Historical vegetational changes of Utah Lake plant communities are discussed. In this discussion, the plant communities described by Cottam in 1925 are examined in broad outline and then in detail. In 1968, twenty-nine plant communities had developed from fifty-six per cent of the associations and twenty-nine per cent of the societies that were described by Cottam in 1925.

Aquatic fungi in-Powell's Slough were.studied in 1967 & 1968. Collections were made and water temperature, oxygen content & pH values were measured at weekly intervals. For collections, wire baskets containing substrata were submerged in water for one month. After collecting, substrata were brought to the laboratory. Identification was based on the keys of Sparrow, 1960. Aquatic fungi identified included seven orders, nine families, fifteen genera, and thirty species, from thirty-three collections of fifteen types of substrata. The substrata used in this study were: (i) fruits: apples, rose hips, plums, pears, haws; (ii) twigs: poplar, weeping willow, river birch, weeping white birch, pine, sumac, roseleaf mountain ash; (iii) others: algae, snake skin, fish head. Blastocladia pringsheimii was the predominant species, found on twelve different types of substrata. The number of species increased both in spring and in autumn, and decreased in summer.

The ecological life history of tall bluebell, Mertensia arizonica Green var. leonardi (Rydb.) Johnston (M. leonardi Rydb.), was investigated during 1963 and 1964. Summer field studies were conducted on the Mud Creek Sleep Allotment of the Uinta National Forest, Wasatch County, Utah. Laboratory and herbarium studies were carried out at Brigham Young University. Specific objectives were to investigate seed germination, seedling development, root system, phenology, palatability, and describe the physical site factors where bluebell occurred. A study of this species was necessary because much of the herbage produced in certain areas of aspen range is not utilized. This condition occurs when mature stems become infected with powdery mildew during mid-July, collapse onto the ground, and dry up. This plant also becomes the dominant forb under certain grazing conditions, and appears to crowd out other desireable forage species. This tall bluebell species occurs throughout the length of central to northern Utah and into southwestern Wyoming and southeastern Idaho, constituting up to 37.1 percent of the understory ground cover. The seed have impermeable seed coats with scarification resulting in a germination percentage of 0.0 to 26.0. Emergence percentages of 21.0 to 53.0 were obtained from field plantings. The period of greatest seedling mortality coincided with the development of permanent wilting conditions at the 6 and 12 inch soil depths during both summers of field study. Studies of transplanted seedlings show that 1 to 2 years of developmental growth are required prior to developing the first single flowering shoot. Mature root systems consist of a semi-fleshy "caudex" from which several main roots extend to a depth of 3 to 4 feet and terminate in fine roots extending beyond to a depth of about 7 feet. Numerous fine roots are concentrated in the upper 1 to 3 feet of soil. Variations in soil texture, structure, pH, total soluble salts, and percent organic matter were not found to alter the basic pattern of root development and distribution. Once plants are established, active growth of stems commences at time of snow melt, and continues 6 to 7 weeks when an average height of 19.5 to 31.0 inches has been reached. Stems elongate as much as 1.4 inches per day with a peak occurring midway in the growing period. Flowering begins about 4 weeks after snow melt and lasts 2 to 4 weeks. Mature seed are shed 18 to 28 days after flowers open. Temperature appears to constitute a significant factor of initial growth and flowering rates. Lodging of bluebell stems occurs with wilting or fast falling rain. The first severe wilting occurs between July 21 and August 13. This coincides with the occurrence of permanent wilting conditions at the 6 and 12 inch soil depths. Wilting is followed by maturation and drying of stems. The latter event is often associated with mildew infection caused by Erysiphe cichoracearum. The occurrence and rate of increasing infection appears favored by high temperature and low humidity. Sheep utilize bluebell up to 44 percent by mid-July. Cattle utilize bluebell up to 46 percent, while deer were not found to utilize bluebell at all. The pocket gopher, Thomomys talpoides was also observed to utilize bluebell stems and inflict injury to main roots.

During the summer of 1934 this investigation was conducted to determine the effect of overgrazing on the mortality of desert browse in the vicinity of the Desert Range Branch experiment station. Range lands of western United States have, as a whole been subjected to overgrazing. Utah has about 24 million acres of public acres of public domain that can only be utilized from grazing. An effort has been made to put this area under control. The "Taylor Grazing Act" passed by Congress June 28, 1934 is a big step in the direction of the control of this vast area of unappropriated range land. This control is necessary in order to rid these ranges of the evils of overgrazing, and save one of the chief resources of the Western States.

A taxonomic and ecological survey of the algae of Lilly Lake in the Uinta Mountains, Utah, was carried on from June 1967 to November 1967. The lake is a typical acid bog lake with an average pH range of 4.5 to 6.9. Extremes of pH in the alkaline range were present due to additional factors. Algae identified included 96 genera and 208 species. These were found in many different types of microenvironmental niches. The main factors which limited the algae to definite areas of the lake were pH, water temperature, light available, and type of substrate. The predominant algal genera uresent in all parts of the lake at all times of the growing season were Scenedesmus, Pediastrum, Microcystis, Aphanocapsa, Sphaerocystis, Spirogyra, desmids, and diatoms. Algae that thrived only under cold water, acid conditions were Eunotia., Culinclrocystis, Euglena, and Chlamydomonas. Genera that grew abundantly when the pH increased to the alkaline range were Dictyosphaerium, Lepocinclis, Phacus, Synura, Pandorina, and Trachelomonas. The most dominant genus in the center stations of the lake was Chara. Fishing and resultant pollution of the marginal waters caused large, bright green blooms of Spirogyra. Algae that appeared in greatly disturbed areas were Closterium and Oscillatoria. Planktonic algae or drifters were not present floating in the water but did occur in the marginal areas where seepage provided necessary nutrients.

Spanish Fork Canyon is located in central Utah and is part of the Wasatch Mountain range. Since the coming of the white man to this section of country it has been used as a trail. The canyon provides summer range for stock as well as a watershed. Plant densities were determined by the point observation method using series of one-hundred square foot plots. Three areas which have been subject to different grazing uses were studied. The association changes in the canyon are the replacement of sage by slender wheatgrass on the shallow soils and the disclimax condition resulting from over-grazing and fire with the annuals Bromus tectorum and Salsola pestifer replacing the true climax. The sage of protected alluvial fans shows rapid growth recovery and reproduction.

No description available.

Thesis (M.A.)--Brigham Young University. Dept. of History. / Includes bibliographical references (leaves 159-164).