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Early Life History Of The Mountain Whitefish Prosopium Williamsoni (Girard) In The Logan River, Utah, Lawrence Guy Brown
Early Life History Of The Mountain Whitefish Prosopium Williamsoni (Girard) In The Logan River, Utah, Lawrence Guy Brown
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Growth and food habits of 399 Age 0 mountain whitefish from the Logan River, Utah, were studied between March, 1970, and April, 1971. At the end of their first six months of life, whitefish were 86-96 mm total length and weighed 6-8 grams (wet). Total temperature experience was 2,950-3,430 degree-days above 32° F. The length-weight relationship for Age 0 mountain whitefish was best described by three stanzas with slopes of 4.3333 for fish 12.5-17.0 mm total length, 3.4437 for fish 17.0-55.0 mm total length, and 2.8043 for fish 50.0-112.0 mm total length. Scalation commenced at 30-35 mm total length and …
Reproduction And Hematology Of The Cache Elk Herd, Thomas B. Follis
Reproduction And Hematology Of The Cache Elk Herd, Thomas B. Follis
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The initial three years of a 10-year reproductive study of elk involved three major phases. A fourth was added because of convenience. Objective 1 was to ascertain pregnancy rates in yearling and mature elk by rectal palpation, associate these rates with subsequent fall cow/calf ratios, and to test concurrently an ultrasonic fetal heart detector. Rectally observed anatomical changes in gravid uteri of cattle were directly applicable to elk. Ultrasonic detections of pregnancies in elk and deer were unsuccessful.
Pregnancy rates in the 1969-70 winter of 100 and 0 percent, respectively, for 19 adult and five yearling elk were associated with …
Some Aspects Of Conditioning Behavior In Rainbow Trout, Salmo Gairdneri, Reed E. Harris
Some Aspects Of Conditioning Behavior In Rainbow Trout, Salmo Gairdneri, Reed E. Harris
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Effects of exercise, social facilitation, and delayed conditioning after vi exercise on the learning behavior of 5 to 6-inch rainbow trout, Salmo gairdneri, was measured in a conditioned avoidance response apparatus. The conditioning schedule contained an intertrial interval between alternate presentations of conditioned (light) and unconditioned (shock) stimuli. This randomization eliminated learning losses found in a previous study. Mean percentage avoidance, the measurement of learning, did not decrease significantly during conditioning trials. Exercised fish learned avoidance better than did non-exercised fish. Mean percentage avoidance for fish exercised at 0.5 ft/sec was 66.3; at 1.0 ft/ sec, 1.5 ft/sec, and …
Population Biology Of The Black-Tailed Jackrabbit (Lepus Californicus) In Northern Utah, L. Charles Stoddart
Population Biology Of The Black-Tailed Jackrabbit (Lepus Californicus) In Northern Utah, L. Charles Stoddart
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Population biology of the black-tailed jackrabbit population on a 250-square-mile area in Curlew Valley, northern Utah, was studied from 1962-70. During this period the fall population density index increased from 40.0 in 1962, to 60.6 in 1963, decreased progressively to a low of 21.2 in 1967, then increased the following 3 years to a high of 185.0 in 1970.
Breeding was synchronous with four conception periods each year; in some years a fifth conception period was evident. The first conception period occurred about the last half of January; other periods followed at 40-day intervals indicating a 40-day gestation period and …
Host-Parasite Relationship Studies Of The Larval Alfalfa Weevil And The Ichneumonid Parasite Bathyplectes Curculionis (Thomson), Yeboa A. Duodu
Host-Parasite Relationship Studies Of The Larval Alfalfa Weevil And The Ichneumonid Parasite Bathyplectes Curculionis (Thomson), Yeboa A. Duodu
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The parasitic effects of the ichneumonid Bathyplectes curculionis (Thomson) on the larval alfalfa weevil, Hypera postica (Gyllenhal), were studied.
Results of experiments on the rates of parasitism of the four host larval instars indicated that the first three are either preferred by the parasite over the fourth instar larvae or are more susceptible to the parasite's attack. Survival of the younger weevil larvae after their exposure to female parasites was markedly poorer than that of unparasitized larvae. Premature death of host larvae was probably from both the puncturing by the parasite's ovipositor and the feeding and other activities of parasite …
Induction And Initial Characterization Of Male-Sterile Mutants On The Second Chromosome Of Drosophila Melanogaster, Susan M. Graves
Induction And Initial Characterization Of Male-Sterile Mutants On The Second Chromosome Of Drosophila Melanogaster, Susan M. Graves
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Fourteen recessive, male-sterile, autosomal mutants of Drosophila melanogaster were induced using ethyl methanesulfonate. The techniques employed restricted the recovery of mutants to those located on the second chromosome. Eleven of the mutants were male-sterile at 23°C, and the remaining three, though fertile at 23°C, were male-sterile at 28°C. Complementation tests involving all possible pairs of mutations showed each to be located in a unique cistron.
Spermiogenesis in each mutant was studied by light microscopy to determine the stage at which cellular differentiation deviates from normal and to characterize the associated gross abnormalities. Phase contrast microscopy showed that each mutant sterile …
Inorganic Mercury Uptake And Mercury Tolerance Demonstrated By Several Species Of Algae, Daniel S. Filip
Inorganic Mercury Uptake And Mercury Tolerance Demonstrated By Several Species Of Algae, Daniel S. Filip
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The inhibition by low concentrations of inorganic mercury has been established for several species of freshwater algae, and a method has been developed to determine mercury levels in algal cells, having good precision at levels as low as one hundred parts per billion.
Rapid sorption of inorganic mercury by glassware was minimized by using heavy algal cultures and short term incubations. The rates and extent of mercury uptake by three species of freshwater green algae were delineated under laboratory conditions. Replicate mercury containing cultures yielded slightly different mercury concentrations upon analysis due to analytical errors and glass sorption. Therefore, percent …
Spermiogenesis In Two Male-Sterile Third-Chromosome Mutants Of Drosophila Melanogaster, Richard F. Wilkinson
Spermiogenesis In Two Male-Sterile Third-Chromosome Mutants Of Drosophila Melanogaster, Richard F. Wilkinson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
An ultrastructural study of sperm differentiation was made on two male-sterile mutants of Drosophila melanogaster. The mutations were induced on the third chromosome with the monoalkylating agent ethyl methanesulfonate and were maintained in stock cultures over a balancer chromosome using a system of multiple inversions. The stages of sperm differentiation, a most dramatic form of cellular differentiation, were then studied at the electron microscope level to determine the effect of the mutations on sperm structure and to correlate those changes with normal sperm development.
Studies of the genetic control of cellular differentiation have been hampered by difficulties in devising …
Radioimmuno Detection Of Virus, John Carlos Perez
Radioimmuno Detection Of Virus, John Carlos Perez
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The commonly used techniques for viral detection are tedious, time consuming and in many cases inadequate. As a consequence, a rapid, sensitive radioimmunoassay has been developed for detecting viruses. Reovirus is reacted with homologous 125I labeled antibody after which the antigen-antibody complexes are separated from unreacted labeled antibody by density gradient ultracentrifugation. After centrifugation, the density gradient is fractionated and the radioactivity counted in a liquid scintillation spectrometer.
The amount of activity in the lower fractions of the density gradient is directly proportional to the virus concentration. The radioimmunoassay developed has several advantages over other viral assay procedures; the …
An Analysis Of Flock Organization In Black-Capped Chickadees, John Ivan Mosher
An Analysis Of Flock Organization In Black-Capped Chickadees, John Ivan Mosher
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
An analysis was made of individual behavior and flock organization among 33 color-banded Black-capped Chickadees (Parus atricapillus) on a woodland tract in wester New York State, from December 1967 to June 1970. Also, three of these flocks were confined at various periods for an average aviary tenure of 26 days. From these observations I concluded that the hierarchy and interindividual relationship of a flock remain as observed in the field; testosterone propionate causes an increase in injected subordinate bird's activity; but did not effect a change in its rank.
From the observations in the aviary, it was found …
Nitrification Potential In Arid Western Soils, Hasumati R. Patel
Nitrification Potential In Arid Western Soils, Hasumati R. Patel
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Nitrification rates were determined by perfusion method in Southern Curlew Valley (Utah) soils from 0 to 1.3 meter profiles as a function of seasons. Ammonification rates were determined at various moisture contents and seasonal variations of ammonium concentration in the same soils were estimated.
Rate of nitrification was higher in warm showery periods (May and June) than in colder periods (September, October and November). In the top 3 cm layer, nitrifying activity was several fold higher than in the rest of the profile. Cultivation increased the nitrification rate.
Considerable ammonium fixation by soil particles, volatilazation of ammonia and nitrite accumulation …
Low Temperature Germination Of Tomato Seeds, Dawn M. Gatherum
Low Temperature Germination Of Tomato Seeds, Dawn M. Gatherum
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this study was to determine the pattern of inheritance of low temperature germination of tomato. This was accomplished by crossing a tomato (P.I. 341988) that germinates at a low temperature (10 C) with a commercial mechanical harvest cultivar (VF 145-B-7879). The parents, F1, F2, and F3 progenies were tested for low temperature germination responses at 10 C for 15 days. The results show that a single recessive gene is responsible for the low temperature germination character.
Also, a study of the seed coat thickness of the tomatoes VF 145-B-7879 and P.I. 341988 was …
Petrology Of The Ordovician Swan Peak Formation, Southeastern Idaho And North-Central Utah, Warren J. Schulingkamp Ii
Petrology Of The Ordovician Swan Peak Formation, Southeastern Idaho And North-Central Utah, Warren J. Schulingkamp Ii
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Swan Peak Formation in southeastern Idaho and north-central Utah is a sedimentary unit consisting of orthoquartzite, sandstone, siltite, shale, and limestone. The formation is divisible into three members, and the lower two members each are divisible into two informal lithologic subunits.
The lower member consists of a lower subunit of gray, calcareous sandy siltite composed of subangular to subrounded quartz grains cemented by quartz overgrowths, calcite, or iron oxide, and an upper subunit of black shale with minor interbedded silty quartzose sandstone and biomicrite (limestone).
The middle member consists of a lower subunit of interbedded pale green shale and …
Canopy Structure And Phenology Of Alpine Tundra Vegetation, Marcee Fareed
Canopy Structure And Phenology Of Alpine Tundra Vegetation, Marcee Fareed
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
An inclined point frame was used to measure leaf area indices in an alpine tundra Kobresia stand and Deschampsia meadow on Niwot Ridge, Colorado. Measurements were made throughout the summer of 1971 at various heights in the canopy and for each species in the two communities. Maximum leaf area indices of 2.2 and 2.0 occurred in the Kobresia and Deschampsia sites, respectively. The Kobresia site was characterized by a single dominant species, Kobresia myosuroides, and a predominance of vegetation within 2.5 cm of mean ground level. The Deschampsia site had no single dominant species. The region of maximum foliage …
Effects Of Several Solutes And Water Stress On Succinic Dehydrogenase Activity, Rex Alton Richards
Effects Of Several Solutes And Water Stress On Succinic Dehydrogenase Activity, Rex Alton Richards
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The influence of the concentration of several solutes on the activity of succinic dehydrogenases from acetone powders of several species was studied spectrophotometrically. The plants used were: Cauliflower (Brassica oleracea var. botrytis, L.) sugarbeet (Beta vugaris, L.) sunflower (Helianthus annus, L.), Halogeton glomeratus (M. Bieb) C.A. Mey., and Samphire (Salicornia rubra, A. Nels.). Sodium chloride, potassium chloride, mannitol, sucrose, glycerol, glucose, and Hoagland's solution, at increasing concentrations, were used.
Decreased (more negative) osmotic potential produced by sodium chloride, potassium chloride, and Hoagland's solution resulted in a slight increase in enzyme activity at low …
A Cytological, Morphological, And Anatomical Study Of Elymus Simplex, Stephan L. Hatch
A Cytological, Morphological, And Anatomical Study Of Elymus Simplex, Stephan L. Hatch
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this paper is to clarify the taxonomy, report the chromosome number, report meiotic chromosome behavior, and give the anatomy of Elymus simplex Scribner and Williams. The isotype of Elymus simplex and the type description were used to compare this and other species that have been confused.
Cytological and anatomical methods are reported as an aid in clarification of the taxonomic problem that has been associated with this species.
A Study Of The Biology Of The Species Of Protocalliphora In The Northern Wasatch Range, Terry L. Whitworth
A Study Of The Biology Of The Species Of Protocalliphora In The Northern Wasatch Range, Terry L. Whitworth
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A total of 733 bird nests, representing 55 species from 23 habitats, was examined. Forty-nine percent of the nests of 39 bird species were infested with 16 species of Protocalliphora.
Infestation of bird nests by Protocalliphora is believed to be related to a number of factors, which are discussed. Loosely constructed nests, nests heavily saturated with feces, and nests occupied early in the season had low rates of infestation. Nests of colonial birds were more frequently infested than those of solitary birds. Nests of some birds were rarely or never infested.
Sixteen species of Protocalliphora are differentiated and their …
Spawning And Early Life History Of Largemouth Bass (Micropterus Salmoides) In Wahweap Bay, Lake Powell, Kent D. Miller
Spawning And Early Life History Of Largemouth Bass (Micropterus Salmoides) In Wahweap Bay, Lake Powell, Kent D. Miller
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Spawning time and habitat of largemouth bass, survival of embryos, and growth and food habits of fingerlings were studied in 1968 and 1969 at Wahweap Bay, Lake Powell. Spawning began in mid- to late-April, when mean daily water temperature at nesting depths was 14.4-15.0 Centigrade (58-59 Fahreheit), and continued until mid-June. Most spawning took place on the northeast shore of the bay. Sandstone rubble was the most commonly used bottom type for nesting, either at the base of ledges or around large sandstone boulders. Mean nest depth increased from 1.63 meter to 4.54 meters (5.36 feet to 14.90 feet) in …
Effects Of Dmso And Propham On Mitosis In Root Tips Of Secale Cereale, Max Rosequist
Effects Of Dmso And Propham On Mitosis In Root Tips Of Secale Cereale, Max Rosequist
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
DMSO (dimethyl sulfoxide) and propham (isopropyl carbanilate) were investigated to determine their effect singly and in combination on mitoses in rye (Secale cereale) root tip cells. Root tips were prepared for observation by the paraffin and aceto-carmine squash methods. Results showed DMSO caused the following abnormalities: arrested metaphases, multipolar spindles, multinucleate cells, stickiness, shortened chromosomes, and mitotic inhibition. Cells from propham treated root tips exhibited the same abnormalities as those treated with DMSO. In addition, propham treatments resulted in polyploid cells and chromosome granulation. In combination, DMSO and propham caused all the abnormalities mentioned above except polyploidy. In …
Ribose 5'-Phosphate Aminotransferase Of Salmonella Typhimurium, Gulamnabi Y. Vahora
Ribose 5'-Phosphate Aminotransferase Of Salmonella Typhimurium, Gulamnabi Y. Vahora
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Ribose-5 '-phosphate aminotransferase, an alternate first enzyme in the purine de novo pathway, has been purified about 800-fold from Salmonella typhimurium (pur D-55 ). The enzyme is distinct from ribosylpyrophosphate-5'-phosphate amidotransferase (E C 2.4.2.14), has an approximate molecular weight of 229,000, and requires ribose-5'-phosphate, ATP and either ammonium ion, carbamyl phosphate or L-glutamine, to synthesize 5'-phosphoribosylamine (PRA). A coupled assay system, employing a S. typhimurium (pur G-310) extract as the coupling-agent source, was used to measure the enzyme. PRA production in this system was inhibited by higher ribose-5' -phosphate concentrations and longer (over 10 minutes) incubation periods. It …
The Effects Of Available Water Upon Populations Of Chukar Partridge On Desert Mountains Of Utah, William W. Shaw
The Effects Of Available Water Upon Populations Of Chukar Partridge On Desert Mountains Of Utah, William W. Shaw
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The importance of surface water to chukar partridges (Alectoris graeca) and the feasibility of rain-catchment devices for improving chukar habitat were studied on the Thomas and Dugway Mountain Ranges in western Utah during 1969 and 1970.
Sources of surface water were removed from one mountain range, and chukar populations on that range were compared with populations on an adjacent range with permanent sources of water.
Providing drinking water did not improve chukar productivity, survival, or availability to hunters. Although most birds concentrated around water supplies in the summer, some chukars appeared to live completely independent of any permanent …
Polymerization Of Tobacco Mosaic Virus, Fabian Crespo V.
Polymerization Of Tobacco Mosaic Virus, Fabian Crespo V.
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
An organic chemical condensing reagent, 1-cyclohexyl-3-(2-morpholinoethyl)-carbodiimide metho-p-toluene sulfonate (CMC) was tested for effectiveness in inducing polymerization of short lengths of tobacco mosaic virus (TMV) nucleoprotein particles isolated from systemically infected Turkish tobacco leaves. It appeared that the chemical induced the formation of phosphodiester linkages between the viral RNA helices in the joining nucleoprotein fragments. Because the polymerization reaction liberates a hydroxyl ion with each joining event the kinetics of the polymerization can be followed with time using a pH meter. The number of hydroxyl ions liberated is equal to the number of polymerizations. Physical evidence of polymerization was obtained by …
A Comparison Of Technologist Needs And Training Requirements Of The Major Industries Within The State Of Utah, Gene E. Forsberg
A Comparison Of Technologist Needs And Training Requirements Of The Major Industries Within The State Of Utah, Gene E. Forsberg
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The technologist needs and training requirements were determined from a selected cross-section of Utah industrial firms.
The larger industries were significantly more aware of the training requirements and capabilities of four-year technologists than were the smaller firms.
A significant difference was found regarding general and specialized training required by each firm. Thirteen of the 16 responding firms indicated specialized training as being most important.
The 10 areas of technical training rated most critical in their order of importance were: electronics, technical writing, electricity, English, mathematics (calculus and above), machine shop, manufacturing processes, physics, and metallurgy and design.
There was no …
Investigation Of Urolithiasis Occurring In Hatchery-Reared Trout In Utah, Ernest H. Dean Jr.
Investigation Of Urolithiasis Occurring In Hatchery-Reared Trout In Utah, Ernest H. Dean Jr.
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The urolithiasis condition investigated occurred at a "hard water" hatchery in Utah after the trout were changed from a meat diet to a commercial pelleted fish feed as a sole sustaining diet in 1961. Numerous diet modifications proved unsuccessful in preventing urolithiasis at the hatchery. It was eventually determined that different commercial diets resulted in varied percentages of trout developing urolithiasis. The urolithic deposits found in the kidney tubules were amorphous and composed of calcium phosphate (apatite) and an organic matrix. Bacterial contamination of the kidneys was not an important factor in the formation of urolithiasis. Rainbow trout containing urolithic …
Ecology Of Badgers In Curlew Valley, Utah And Idaho With Emphasis On Movement And Activity Patterns, Frederick G. Lindzey
Ecology Of Badgers In Curlew Valley, Utah And Idaho With Emphasis On Movement And Activity Patterns, Frederick G. Lindzey
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Between March, 1969 and July, 1970, 16 badgers (Taxidea taxus) were caught and fitted with radio transmitters in the southern part of Curlew Valley. The animals were followed telemetrically; seven animals contributed sufficient data from which home-range, movement and activity patterns could be discerned. The aver age annual home-range size of five females was 664 acres (± s.d. 99 .5 acres). Female home-range sizes were approximately the same within crested wheat-grass (Agropyron aristatum) and sagebrush (Artemisia tridentata) vegetation types, with greater distances traveled each night by females in the crested wheat-grass. Both home-range size and total movement were less …
The Suitability Of Newton Reservoir To Be Either A Coldwater Or A Warmwater Fishery, Jeffrey H. Johnson
The Suitability Of Newton Reservoir To Be Either A Coldwater Or A Warmwater Fishery, Jeffrey H. Johnson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Measurements were made of the water chemistry the distribution and relative abundance of net-plankton, and the reproduction, age and growth, and food habits of largemouth bass in Newton Reservoir, Newton, Utah.
Samples for chemical analysis were collected weekly from three sites and from several depths at each site. Plankton collections were made on a monthly basis. Data were compared with data in the literature and analyzed for possible ecological implications.
Physical and chemical investigations of the water indicated favorable conditions for a warmwater fishery.
The study of the surface net-plankton revealed a predominance of blue-green algae.
The substratum of the …
Investigations Into The Microbial Ecology And Limnology Of Hyrum Reservoir, In Northern Utah, Kenneth Maxwell Green
Investigations Into The Microbial Ecology And Limnology Of Hyrum Reservoir, In Northern Utah, Kenneth Maxwell Green
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A series of preliminary investigations was carried out to determine the factors promoting the dense, late summer waterblooms of Aphanizomenon flos-aguae in Hyrum Reservoir in northern Utah. Attempts were made to culture the Aphanizomenon in the ASM-8a medium of O'Flaherty and Phinney (J. Phycol. 6:95-97. 1970), but no growth was obtained and the algae soon lysed. Cultures were maintained, without growth, for more than four months in a lake water--lake sediment medium at 17 C under 1500 lux flourescent light.
Dissolved oxygen measurements using an in situ probe revealed the development of a sharp oxycline during the summer months; on …
An Evaluation Of A Self-Guided Visitor Tour At Bear River Migratory Bird Refuge, Steven J. Kohler
An Evaluation Of A Self-Guided Visitor Tour At Bear River Migratory Bird Refuge, Steven J. Kohler
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In 1967 this study was initiated to evaluate the self-guided visitor tour of Bear River Migratory Bird Refuge. A 20 page visitor information booklet and tour guide was prepared and published for distribution at the refuge, and its effectiveness in telling the refuge story was evaluated. To gain a measure of the self-guided tour in terms of quality, visitor use patterns and satisfactions were critically examined.
To gather data on visitor use of the refuge, the visiting public was directly sampled by three methods: mail questionnaires, on-site interviews and candid tower observations of groups on the tour.
The information and …
The Nitrogen Budget Of Two Salt Desert Shrub Plant Communities Of Western Utah, Richard S. Bjerregaard
The Nitrogen Budget Of Two Salt Desert Shrub Plant Communities Of Western Utah, Richard S. Bjerregaard
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The nitrogen budgets of Eurotia lanata (Pursh.) Moq. and Atriplex confertifolia (Torr. and Frem.) S. Wats salt desert shrub plant communities were investigated. In each, a complete biomass and organic nitrogen inventory was made. In addition, investigations of the nitrogen fixation potential of soil surface microflora and inorganic soil nitrogen relationships were carried out.
Greater total biomass and organic nitrogen was found in the above-ground portions, annual shoot productivity, and litter of the Atriplex community. However, the Atriplex community was exceeded by the Eurotia community in root biomass. Roots accounted for 74 and 87 percent of the plant biomass and …
Ecological Life History Of Rudbeckia Occidentalis Nutt, Juan Arturo Florez
Ecological Life History Of Rudbeckia Occidentalis Nutt, Juan Arturo Florez
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Phenological studies of coneflower on aspen range in Northern Utah showed that resumption of growth of mature plants begins at the time of snow melt and the initial or rosette stage is completed between mid-May and mid- June. The rate of growth in this stage is controlled by temperature, being greater at higher mean temperatures. The bolting stage is completed about 1 week after the initiation of stem elongation and the process of capitulum development is begun. Flowering is initiated between late July and mid- August. Cross-pollination is necessary for seed set which is completed by the end of August. …