This investigation was concerned with the taxonomic relationship between Astragalus beckwithii (Torr. & Gray) var. beckwithii, Astragalus oophorus (S. Wats) var. caulescens (Jones) Jones, and Astragalus megacarpus (A. Gray). An attempt was made to relate some chemical constituents and the toxic effects on rats to the taxonomy. A number of parameters were used; rat toxicity, lipid analysis, selenium atomic absorption, various salts and glucose percentages, as well as the usual morphological measurements taken from herbarium specimens, field observations, and pollen measurements. While the weight of the data indicates that A. beckwithii is a type of intermediary or intergressory product of A. oophorus and A. megacarpus, and that it very closely resembles A. oophorus, it would be premature to suggest combining A. beckwithii and A. oophorus until the related varieties in each species are also studied. Evidence shows definite symptoms of locoism in the white rats tested. A hypothesis was made that the toxic principles in these plants are associated with the nitrile compounds.

It was the purpose of this study to determine what aquatic plants were common to central Utah and to outline the ecological factors that control their distribution. The main emphasis throughout has been upon the more macroscopic aquatic plants. Such algae were included as was warranted by their size,, abundance and importance in the various habitats in which they grew. As this study progressed it became evident that there was a need for a broad survey-type study of the aquatic plants that would include essentially all of the wet lands of the central Utah region. The area of study closely corresponds to the boundaries of Utah County, although some collections were made outside the county, particularly to the east, in Wasatch County. The study was initiated in the spring of 1955 and field work was done during the summers of 1956, 1957, and 1959.

A study was made of the ecology and floristics of a small bog lake referred to as Moss Lake, in the Grandaddy lakes region of the Uinta Mountains , Utah . Three consecutive summers, 1948, 1949, and 1950, were spent in collecting the data presented in this study. Throughout the study the following ecological measurements were made: 1. Water 2. Soil 3. Macroscopic vegetation 4. Plankton 5. Macroscopic animal forms.

The purpose of this study was to measure quantitatively the effectiveness of precipitation by determining the amount and timing (i.e. distribution-in-time) of plant absorption of moisture during the summers of 1965 and 1966. In addition the effectiveness of precipitation was related to some causal factors, especially those factors which help provide a procedure for calculation of this effectiveness.

The sand dunes lying ten miles northwest of Kanab in Kane County, Utah, support a sparse plant cover with four species dominating the vegetation: Psoralea stenostachys, Sophora stenophylla, Oryzopsis hymenoides, and Wyethia scabra var. attenuata. Of these Psoralea and Wyethia are endemic to the dunes or to a limited area which includes the dunes. The pineer species gain a start in the valleys between dunes and occupy the area only until sand covers them or until sand is blown away from their roots. Stabilization of the soils is not permanently in the interdune valleys and the dunes continue to wander. The low fertility of the soils, the low moisture content, the extremes of temperature, light, and other environmental factors limits the number of individual plants which can occupy the dunes. The region will continue to have actively moving dunes until major climatic changes occur permittimg a denser plant cover which would tend to stabilize the sands.

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.