The American Bison in the Henry Mountains are one of the last free-roaming, genetically pure herds of bison remaining in North America. Over the last decade, the herd has used a cattle winter range during the summer and early fall, creating a conflict between the wildlife officials who manage the bison population, and BLM officials and local ranchers who manage the rangeland.

Wellsville Mountain is 10 miles west of Logan, Utah, at the northern extremity of the Wasatch Range. Paleozoic rocks forma northeast-dipping homocline bounded in part by northwest-trending high-angle faults and cut by a series of northeast-trending high-angle faults. A major transverse fault, with a stratigraphic displacement of 4,500 feet, divides the mountain into two distinct blocks. The rock units of the area are comparable to those of the Logan quadrangle immediately to the east. Pre-Cambrian rocks crop out in Box Elder Canyon, just east of Brigham City, and are overlain by at least 20,000 feet of northeast-dipping Paleozoic rocks of every period except possibly the Permian. The Beirdneau sandstone member of the Jefferson formation, is tentatively correlated with that of the upper Devils Gate limestone of central Nevada. About 6,600 feet of the Oquirrh formation of Pennsylvanian age is exposed near the northern end of Wellsville Mountain. The presence of Desmoinesian fusulinids at the base of the Oquirrh and upper Virgilian fusulinids throughout the interval from 1,000 to 2,000 feet above its base indicates an absence of Lower Pennsylvanian rocks and suggests that the upper 4,400 feet may be in part Permian. Mesozoic rocks are not found in the area. The Wasatch formation and Salt Lake group of Tertiary age crop out in the foothills at the northern end of Wellsville Mountain. Two fault systems are recognized in the area. The northeast-trending high-angle transverse faults of Laramide age and the north-west-trending high-angle bordering faults are Basin and Range age.

Geologic mapping, facies analysis, sedimentary petrography, and detrital zircon analyses of undivided eastern Uinta Mountain Group stratigraphy are presented to better understand the depositional environments and tectonic setting of the Uinta Mountain Group basin. Subdivided units have been modified and correlated from previous work and include the Red Pine Shale, Hades Pass, Crouse Canyon, Outlaw Trail, and Diamond Breaks formations. Three lower-order maximum flooding surfaces associated with the lower Outlaw Trail formation, lower Hades Pass formation, and Red Pine Shale are interpreted. The relative magnitude of each lower-order transgression increases up section along with increasing diversity of palynomorph assemblages found in organic shale intervals. Six facies associations exist within the section and are interpreted as braided fluvial conglomerate, braided fluvial sandstone and conglomerate, braided fluvial sandstone, low-energy braided fluvial sandstone, mudflat, and offshore depositional environments. Both marine and non-marine interpretations are plausible for mudflat and offshore environments; however, previous interpretations of correlative Red Pine Shale exposures suggest a marine environment. The coarsest fluvial environments are restricted to the northern half of the study area and likely coincide with proximity to a tectonically-active northern basin margin. Paleocurrent analysis and the restriction of some subaqueous deposits to the north show northward-dipping depositional slopes, which suggest a tectonic control. Provenance work suggests three general sediment sources existed: an eastern source where ~1.1 Ga and lesser ~1.4 Ga detritus dominate, an east-northeastern source where ~1.8 Ga detritus dominate, and a north-northeastern arkosic source where ~2.7 Ga detritus dominate. Results suggest that during lower-order lowstands, sediments derived from eastern sources dominate. Higher concentrations of ~1.8 Ga and ~2.7 Ga detritus is likely coincident with proximity to the northern basin margin. During lower-order highstands, eastern or northern sources may dominate; northern sources appear more prominently within the Outlaw Trail formation, while eastern sources appear more prominently within the Red Pine Shale. Reasons for this may be linked to the magnitude of the transgressive interval sampled. These relationships, in conjunction with observations of previous studies, suggest the eastern Uinta Mountain Group was deposited in a half-graben style rift, a strike-slip basin, or some combination of the two.

Lodgepole pines Pinus contorta (Douglas) were treated by girdling to assess the response by an endemic population of mountain pine beetle Dendroctonus ponderosae (Hopkins) (Coleoptera: Scolytidae). Capture in 'sticky traps' indicated that the beetles were attracted while in flight towards the wounded trees. A significant difference in the landing rates of bark beetles between the treated and untreated trees indicated that the beetles were able to distinguish wounded from non-wounded trees while still in flight. Pressure chamber readings demonstrated that water stress developed in the girded trees when compared to the non-girdled trees.

The purpose of this study was to quantify the chemical nature of the Chicken Creek waters, and to investigate the variability and causes of that observed chemistry. The three objectives of the study were: 1) inventory the chemistry of the water produced by the subject watersheds, 2) determine chemical budgets for the watersheds, and 3) identify the sources of the primary chemical components. Chemical surveys were made: 1) on the stream exiting from each gaged watershed, 2) at various points within the West Branch drainage network, 3) of the atmospheric inputs (rain, snow, and dust), 4) of the soil solution, and 5) of the soil itself. Data were also collected on the volume and distribution of rain and snow entering the watersheds, and the volume and timing of the streamflow leaving. Streams were found to be dilute solutions with nearly neutral pH, containing Ca, Mg, Na, K, HCO3, SO4, and Cl; with NO3 and PO4 present in lesser quantities. The observed chemistry was quite dynamic with the CO2/CO3/HCO3 equilibrium system having a significant influence. In a more general sense, the water chemistry appeared to be a mixture of surface runoff, with chemistry approaching that of precipitation; and subsurface flow, with chemistry near that of soil solution. The watersheds themselves are the source of most of the chemical constituents, with only NO3 and PO4 appearing to be consumed within the watersheds. On a per unit area basis, the West Branch watershed was shown to produce significantly more water, of higher chemical concentration than the East Branch. Possible explanations for such variability are discussed, e.g., non-uniform distribution of the snow pack and varying chemical activity of soils.

The Sharp Mountain area is situated in the southern part of the Bear River Range in Utah. The geology of the Bear River Range to the north of this area, in Utah and Idaho, has been mapped; however, prior to this study little was known about the Sharp Mountain area. The purpose of this investigation are as follows: (1) to map and describe the geology of the area, and (2) to relate the stratigraphic and structural features of the Sharp Mountain area to those of the surrounding region.

The purpose of this study was to determine if arterial oxygen saturation (SaO2), as measured by a finger pulse oximeter upon rapid arrival to 4260 m, could be predictive of acute mountain sickness (AMS) or summit success on a climb to 5640 m. In total 73 climbers volunteered to participate in the study. After excluding those taking drugs to counteract the effects of AMS and those with missing data, 48 participants (45 male, 3 female) remained. Climbers were transported from 2650 m to the Piedra Grande hut at 4260 m on Pico de Orizaba within 2 hr. After a median time of 10 ± 13 hr at the hut, they climbed toward the summit (5640 m) and returned with a median trip time of 13.3 ± 4.8 hr. The Lake Louise Self-assessment Questionnaire (LLSA) for AMS, heart rate, and SaO2 from a finger pulse oximeter was collected upon arrival at the hut, repeated immediately before the climbers departed for their summit attempts, and immediately upon their return. The presence of AMS was defined as a LLSA score ≥ 3 with a headache and at least one other symptom. Fifty-nine percent of the participants successfully reached the summit. Average SaO2 for all participants at 4260 m prior to their departure for the summit was 84.2 ± 3.8%. Sixty percent of the participants met the criteria for AMS during their ascent. There was not a significant difference (p = .90) in SaO2 between those who experienced AMS (SaO2 = 84.3 ± 3.3%) and those who did not (SaO2 = 84.2 ± 4.2%) during the ascent. Neither was there a significant difference (p = .18) in SaO2 between those who reached the summit (84.8 ± 3.7%) and those who did not (83.3 ± 4.0%). Arterial oxygen saturation does not appear to be predictive of AMS or summit success.

Riparian cottonwoods (populus spp.) are keystone pioneer species that contribute to critical streamside and in-stream habitats, water quality, and aesthetic and recreational value. Land use and river regulation have caused a widespread reduction in the extent and regeneration of this genus. The majority of research on Populus species' reproduction has examined seedling recruitment that dominates in wide alluvial valleys. In contrast, I evaluated reproductive strategies of Populus angustifoliain mountain valleys. Research was conducted in northern Utah on the Little Bear River, a gravel-bedded stream that flows north out of the Bear River Range onto deposits of Ancient Lake Bonneville. I used allozyme electrophoretic data and vegetation mapping to investigate recruitment mechanisms of cottonwoods at two steep, confined mountain valley sites and two wide, alluvial valley sites. Allozyme electrophoretic analysis on samples from sites one through four revealed 60%, 69%, 86%, and 84% clonal recruitment, respectively. The size of cottonwood clones may be on the order of 200-300 m in this system. Vegetation mapping supported allozyme data and suggested that clonal recruitment dominates the system. I also collected data at four sites containing no cottonwoods to compare hydrogeomorphic influences at non-cottonwood (NC) sites and cottonwood recruitment (CR) sites. CR sites possess a distinctive geomorphic template relative to NC sites and this template may facilitate root disturbance resulting in clonal recruitment. A high frequency of woody debris and mid-channel islands characterizes CR sites. Channels at CR sites are less entrenched, more sinuous, and exhibit larger bankfull channel width and width to depth ratios, and finer grain sizes than channels at NC sites. At CR sites, estimates of bankfull average boundary shear stress and unit stream power are less compared to those at NC sites. Cottonwood recruitment models that typically describe seedling reproduction in alluvial valley environments do not apply in narrow, steep-gradient environments. I found clonal recruitment of cottonwoods to correlate spatially and temporally with channel and root disturbance associated with rain on snow events on the order of the 25-30-yr flood event.

A detailed study was made of the James Peak-Sharp Mountain area, in the southern part of the Bear River Range, Utah. The mapped area is located in north-central Utah between lat. 41°22'30" N. and lat. 41°30' N. and long. 111°42'30" W. and long. 111°46' W. It measures about 3.8 miles in the east-west direction and 8.7 miles in the north-south direction. The area is centered about 22 miles south-southeast of Logan, Utah. Stratigraphic units of late Precambrian to Mississippian age underlie the mapped area. The Precambrian units include the Mutual and Browns Hole Formations. The Brigham, Langston, Ute, Blacksmith, Bloomington, Nounan, and St. Charles Formations make up a complete Cambrian section. The Ordovician Garden City and Swan Peak Formations, the Ordovician-Silurian Laketown Formation, the Devonian Water Canyon and Hyrum Formations, and the Mississippian Lodgepole and Humbug Formations overlie the St. Charles in normal succession. The oldest unit the Precambrian Mutual Formation, crops out in the southern part of the area on the eastern side of James Peak. The rock units are progressively younger toward the northern part of the area. Mesozoic rocks are not present. The Salt Lake Formation of Tertiary age directly overlies the Paleozoic rocks. The main structural feature of the area is an asymmetrical north-south-trending anticline. The eastern flank dips more steeply than the western flank. The anticline plunges gently north and dies out southward. This anticline is one of a series of asymmetrical anticlines, all steeper on the east than on the west, that includes the Strawberry Valley anticline to the east and the anticline exposed in upper Wolf Creek Canyon to the west. The late Precambrian and early Paleozoic formations, which dip northeast on the eastern flank of James Peak, make up the northeastern flank of the anticline exposed in upper Wolf Creek Canyon. The early Paleozoic to Devonian formations that form Sharp Mountain and dip gently west make up the western flank of the Strawberry Valley anticline. Low-angle thrust faults have disrupted the Precambrian and Paleozoic formations on the eastern and southeastern flanks of James Peak. Displacement on the thrust fault north of upper Wellsville Creek is about 2,000 feet. Movement was generally from the west. Normal faults have disrupted the Paleozoic and Tertiary formations along the eastern margin of Cache Valley and the Paleozoic formations east of McKenzie Mountain. Displacement is indeterminate along the eastern margin of Cache Valley. Maximum displacement, east of McKenzie Mountain, is about 1,750 feet. The normal faults truncate the folds and thrust faults. The folds and thrust faults were formed during the Laramide orogeny. The normal faults were formed during Basin and Range normal faulting. Basin and Range normal faulting is active at the present time.

Lava flows of Tertiary-Quaternary age occur in Enoch Valley, Upper Valley, and Slug Valley in southeastern Idaho. The basalts in Upper Valley and Enoch Valley contain olivine (Fo69 to Fo37), plagioclase (An62 to An39), augite and Fe-Ti oxides. The lava in Slug Valley lacks plagioclase, but contains sanidine (Or70 to Or56) with a trace of biotite and amphibole, and thus, has been termed alkali trachyte. Black Mountain, on the eastern side of Bear Lake, northeastern Utah, is capped by basalt. Minerals present include olivine (Fo83 to Fo72), plagioclase (An71 to An53 J, augite, and magnetite. Chemically, the basalt of Enoch Valley is comparable to olivine tholeiite of the Snake River Plain, as it contains olivine and hypersthene in the norm. The basalt of Upper Valley contains a greater amount of Si02 and K2O and less MgO than tholeiite of the Snake River Plain. This basalt contains normative quartz and hypersthene and is classified as tholeiite. The presence of nepheline and olivine in the norm of the basalt from Black Mountain indicates that it is an alkali-olivine basalt. The lava from Slug Valley contains high K and Mg, moderate Si, and low Al and Na. It is similar to lamproites of orenditic affinity. The temperatures of crystallization calculated from co-existing olivine and pyroxene, range from 1,015 degrees C to 996 degrees C for the valley basalts, and range from 1,021 degrees C to 1,002 degrees C for the alkali trachyte. The temperature calculated for the basalt sample from Black Mountain is 1,015 degrees C. The temperatures estimated using coexisting magnetite and ilmenite range from 1,021 degrees C to 978 degrees C for the valley basalts. The proposed origin of the Enoch Valley basalt is that it is a direct product of partial melting of a mantle of pyrolite composition. Fractionation, during ascent of the magma, could possibly have produced the Upper Valley lava. The basalt on Black Mountain was possibly derived as the result of partial melting of a pyrolitic mantle as well, but due to differences in mineralogy and normative constituents, it seems to be unrelated to the valley basalts. The origin of the Slug Valley alkali trachyte is uncertain. This lava may have been generated from a mica peridotite mantle and is possibly related to the Leucite Hills lava in Wyoming.