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Thrips Of The Sagebrush-Grass Range Community In West-Central Utah, Ward Max Tingey Aug 1968

Thrips Of The Sagebrush-Grass Range Community In West-Central Utah, Ward Max Tingey

Theses and Dissertations

Three predominant and economically important shrubs of the sagebrush-grass range community in Utah, namely big sagebrush (Artemisia tridentata Nutt.), rubber rabbitbrush (Chrysothamnus nauseosus (Pall.) Britt.), antelope bitterbrush (Purshia tridentata (Pursh) DC), and a widely re-seeded range grass, crested wheatgrass (Agropyron cristatum (L.) Gaertn.) were sampled during the summers of 1966 and 1967, and yielded twenty species of thrips. Three species (Anaphothrips tricolor Moulton, Chirothrips aculeatus Bagnall, Chirothrips simplex Hood) were new distributional records for Utah. Seven species (Frankliniella n. sp. #1, Frankliniella n. sp. #2, Haplothrips n. sp., Leptothrips n. sp., Oedaleothrips n. sp., Sericothrips n. sp. #1, Sericothrips n. …


Vegetational Changes In A Mountain Brush Community Of Utah During Eighteen Years, Robert J. Eastmond Aug 1968

Vegetational Changes In A Mountain Brush Community Of Utah During Eighteen Years, Robert J. Eastmond

Theses and Dissertations

This vegetational analysis is concerned with changes which have cocurred since 1949 in a mountain brush community within an exclosure in the central Wasatch Mountains. The exclosure, established in 1949, is located in Pole Canyon on lower Provo Canyon. Two major studies have been conducted previously, but it has been nine years since the last intensive work was done. Several major changes occurring during the eighteen year period are evident and are described.


A Study Of Multiple Embryo Development In The Netleaf Hackberry (Celtis Reticulata), Gary Porter Lawrence Aug 1968

A Study Of Multiple Embryo Development In The Netleaf Hackberry (Celtis Reticulata), Gary Porter Lawrence

Theses and Dissertations

Previous research has shown that polyembryony occurs in many species of the Ulmaceae. The purpose of this study was to determine the method of multiple embryo formation in netleaf hackberry, Celtis reticulata Torr. Collections of specimens were made throughout a two-year period. Collections were begun in early spring while the trees were still in the bud state. Collections were continued regularly throughout the growing season. The collections were preserved in FAA solution and were prepared for microscopic examination as follows: (1) The tertiary butyl paraffin method was used for dehydrating and embedding. (2) Sectioning was done on a rotary microtome …


Field Observations And Laboratory Studies On Growth And Tillering In Seedlings Of Oryzopsis Hymenoides As Affected By Selected Environmental Factors Of The Sand Dunes Of Lynndyl, Utah, Leopold B. Smigelski Aug 1968

Field Observations And Laboratory Studies On Growth And Tillering In Seedlings Of Oryzopsis Hymenoides As Affected By Selected Environmental Factors Of The Sand Dunes Of Lynndyl, Utah, Leopold B. Smigelski

Theses and Dissertations

Seedlings of Indian rice grass Oryzopsis hvmenoides (Roem. & Shult.) Ricker. were studied to determine the effect of soil moisture, photoperiod, depth of burial of germinated grains, temperature, and the rate of soil accumulation on seedling growth and tillering. The study was performed in two phases: Field observations and laboratory studies. Field observations were made on a system of sand dunes located northwest of Lynndyl, Utah. General observations were made from January, 1966 to May, 1968.


Factors Influencing Production Of Flower Stalks In Agropyron Cristatum (L.) Gaertn, Neil C. Frischknecht Aug 1968

Factors Influencing Production Of Flower Stalks In Agropyron Cristatum (L.) Gaertn, Neil C. Frischknecht

Theses and Dissertations

A study was made of factors that influence production of different numbers of flower stalks of crested wheatgrass on grazed and ungrazed areas. Both laboratory and field studies were made. Greatest response in flower stalk production resulted from application of nitrogen in the field, amounting to an increase of from 5 to 10 times the numbers of flower stalks on untreated areas. Responses of plants in the greenhouse supported these results. Plants grown in the dark indicated that higher carbohydrate reserves existed in ungrazed than in grazed plants. It was concluded that a high carbohydrate-low nitrogen balance was the primary …


Floral Induction In Some Members Of The Umbelliferae In Response To Cold Treatment, Photoperiod, Gibberelic Acid, And Kinetin, A: Glenn Wahlquist Jul 1968

Floral Induction In Some Members Of The Umbelliferae In Response To Cold Treatment, Photoperiod, Gibberelic Acid, And Kinetin, A: Glenn Wahlquist

Theses and Dissertations

This study was undertaken to determine the influence of different treatments of temperature, photoperiod, gibberellic acid, and kinetin on the flowering responses of certain biennial species of the Umbelliferae. Seven species were selected for study, namely: carrots, wild carrots, parsnips, wild parsnips, poison hemlock, celery, and parsley.


Notes On The Fern Family Matoniaceae From The Western United States, Samuel R. Rushforth May 1968

Notes On The Fern Family Matoniaceae From The Western United States, Samuel R. Rushforth

Theses and Dissertations

A Cretaceous fern flora haas been recently discovered near Westwater, Grand County, Utah. Among specimens collected from Westwater are many forms related to extant members of the fern family Matoniaceae. This family was widely distributed geographically throughout most of the Mesozoic Era, and matoniaceous ferns have been collected from several fossil localities in the United States. The Matoniaceae was especially important in the United States during Lower Cretaceous times. Five species, Matonidium brownii Rushforth, Matonidium lanceopennis Rushforth, Matonidium galleyi (Miner) Rushforth, Matonidium americanum Berry em. Rushforth, and Matonidium sp., and one variety, Matonidium brownii var. extenda Rushforth, are considered in …


Ultrastructural Investigations Of Powdery Mildew Of Rose Caused By Sphaerotheca Pannosa (Wallr.) Lev, Ani Clipper Watene May 1968

Ultrastructural Investigations Of Powdery Mildew Of Rose Caused By Sphaerotheca Pannosa (Wallr.) Lev, Ani Clipper Watene

Theses and Dissertations

The purpose of this study was to evaluate the ultrastructural aspects of the host-pathogen relationship between the fungus Sphaerotheca pannosa (Wallr.) Lev. and a susceptible horticultural variety of floribunda rose "Eutin". Attention was given to the penetration of hyphal tubes, and their subsequent development into: haustorial elements in epidermal cells of rose. In addition, changes in the morphology of infected epidermal cells were described. Thin sections of rose leaves infected with S. pannosa were examined in a Hitachi electron microscope, model HS-7, after glutaraldehyde-acrolein fixation, OsO4-uranyl acetate staining, and embedding in Epon plastic. The components of S. pannosa haustoria consisted …


A Study On The Effectiveness Of Precipitation In The Salt Desert Shrub Type, Sam Finley Brewster May 1968

A Study On The Effectiveness Of Precipitation In The Salt Desert Shrub Type, Sam Finley Brewster

Theses and Dissertations

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.


Distribution Of The Major Plant Communities In Utah, Robert Howard Foster May 1968

Distribution Of The Major Plant Communities In Utah, Robert Howard Foster

Theses and Dissertations

Utah is a state containing a complexity of landforms in a unique continental setting which results in a variety of climatic and edaphic conditions. The variety, however, is not expressed on a latitudinal plane from north to south but is primarily altitudinal, changing from the playa or valley floors to the mountain tops. The associated arrangement of vegetation, consequently, is usually according to elevation, the elevation generally regulation precipitation and thus edaphic conditions. Slope exposure and position of landforms relative to storm-tracks are modifiers, and prevent fixed posisions for many vegetation types. Vegetation in Utah is as variable as are …


A Taxonomic And Ecological Survey Of The Algae Of Lilly Lake, Ann C. Palmer May 1968

A Taxonomic And Ecological Survey Of The Algae Of Lilly Lake, Ann C. Palmer

Theses and Dissertations

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 …


A Reconnaissance Of Upper Cretaceous Plants From The Blackhawk Formation In Central Utah, And Their Paleoecological Significance, Lee Ross Parker Apr 1968

A Reconnaissance Of Upper Cretaceous Plants From The Blackhawk Formation In Central Utah, And Their Paleoecological Significance, Lee Ross Parker

Theses and Dissertations

A well-preserved flora has been collected from the Upper Cretaceous Blackhawk Formation near Salina, Utah. This formation is part of the Mesaverde Group and consists mostly of deltaic sediments deposited along the western margin of a Cretaceous sea. The Blackhawk Flora is comprised of the following species: Eguisetum sp., Osmunda hollickii, Allantodiopsis erosa, Saccoloma gardneri, Araucaria longifolia, Ginkgo laramiensis, Protophyllocladus polymorphus, Sequoia affinis, Geonomites imperialis, Sabalites montanus, Dryophyllum subfalcatum, Juglans similis, Cinnamomum sezannense, Magnolia ampifolia, Menispermum dauricumoides, Ficus glasconea, Ficus planicostata, Ficus puryearensis var. elongata, Myrtophyllum torreyi, Nymphaeites dawsonii, Dalbergia (?) prewilcoxiana, Salix lesquereuxii, and Trapa paulula. Two independent studies …