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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Diversity of ectomycorrhizal fungi on two reclaimed surface mines differing in soil properties

Kurnik, Betsy S. January 2000 (has links)
Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains viii, 72 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 61-64).
32

Relationships between Potential Rooting Depth, Tree Growth, and White Pine (Pinus Strobus L.) Decline in Southern Maine

Granger, Gregory January 2004 (has links) (PDF)
No description available.
33

Hydrologic Investigation of the White Pine Bog, Burton Township, Geauga County, Ohio

Keinath, Valerie L. 15 August 2011 (has links)
No description available.
34

Sulphur Isotopes in the White Pine Mine, Ontonagon County, Michigan

Burnie, Stephen W. 12 1900 (has links)
Ore specimens from the cupriferous zone of the basal Nonesuch shale at the White Pine Mine were analysed for sulphur isotopes, carbon and sulphide contents and boron. The results of the analyses were discussed in relation to a biogenic-syngenetic mineralization process for the ore body. A model, based on the δS³⁴sulphide frequency distribution, was developed to determine the δS³⁴ sulphate value of the lower Nonesuch paleoenvironment. A transmitted light microscopic examination of chlorite was undertaken in order to present a more complete picture of this proposed source for copper in the cupriferous zone of the Nonesuch shale. / Thesis / Master of Science (MSc)
35

Mine soil properties influencing white pine (Pinus atrobus L.) growth in Southwest Virginia

Tuladhar, Amulya Ratna January 1986 (has links)
Thirty-six eight-year-old white pine (Pinus strobus L.) trees were used to identify minesoil, plant moisture, and foliar nutrient properties influencing white pine growth on reclaimed mine sites in southwest Virginia. PRESSAll (SAS Views, 1984) was used to determine relationships between soil properties and growth, soil properties and functional environmental factors (plant moisture stress and foliar nutrients), and between functional environmental factors and growth. PRediction Error Sum of Squares (PRESS), Mean Square Error (MSE), and Multiple Correlation Coefficient (R²) were used as criteria for variable selection and model validation. Rooting-volume index, the reciprocal of the electrical conductivity (EC), and extractable P in the soil-sized fraction of the minesoils were the best validated variables, predicting tree heights with the smallest amount of unit error (APRESS of 0.86 m) and accounting for the highest R² ( R² = 53.06%). The depth of the rooting volume had the greatest effect on 2 early growth (R² = 7 .91%), but variation in the last four years of height growth appeared to be a function primarily of rooting volume (R² = 51.40, p < 0.0001). Relationships between soil properties and 2 functional environmental factors varied widely (R² = 0.00-27 .50%). Plant moisture stress was most highly associated with the volume of the soil-sized fraction (R² = 13.6%), foliar phosphorus with soil pH (R² = 22.5%), and foliar cations with anaerobic-mineralizable nitrogen (R² = 0.00-27 .5%). The relationship between functional environmental factors and growth was uniformly weak (R² = 0.00-14.97%). Plant moisture stress was consistently related to overall height and its increment over the last four years, but foliar nutrients were erratically related to growth. No significant relationships between other functional environmental factors and growth were detected. Minesoil indices for individual trees ranged from 47-147 (base age 50). The depth of minesoil for site index 80 (average for Southern Appalachia) was 40 cm. / M. For.
36

The effect of the white-pine weevil (Pissodes strobi Peck) on white pine (Pinus strobus L) in southwestern Virginia

Egan, Peter Joseph John 03 October 2008 (has links)
Thirteen white pine plots, ranging from 15-26 years of age and one tenth acre in size, were sampled in six counties of southwestern Virginia. The number of trees attacked by the white-pine weevil ranged from 3.5 percent to 98.6 percent with an average of 40.0 percent. The incidence of forking was found to be 4.1 percent of the trees weevi1ed. Enough trees in the dominant and co-dominant crOvffi categories were either free of weevil attacks or only attacked once that 250 to 300 trees are available for final harvest. Most of the weevil attacks occurred between 5 to 12 years of age. Analysis of Covariance for non-weevi1ed terminals and lateral lengths developed the following relationship for three age classes of terminals and laterals. / Master of Science
37

Fenuron in the management of white pine

Ditman, William David 09 November 2012 (has links)
Experiments were conducted on the use of granular fenuron, 25% active, for white pine release and establishment. The effect of fenuron on the plant community was also investigated. Studies included in the white pine release experiment were the effect of season of treatment on the kill of hardwoods and percentage survival of indigenous white pine, and the effectiveness of fenuron on various species of hardwoods. All hardwood stems over six feet tall were treated with four grams of active fenuron placed on the soil at the base of the tree. Treatments were made in May 1960, August 1960, and March 1961. The May treatment was most effective in the removal of the hardwoods. There was a reduction of 59% of pines over six feet tall and an increase of 45% of pines less than six feet tall. Red maple and the oaks were the species most susceptible to the treatment; whereas, chestnut, sassafras, and black locust were the least susceptible. In the white pine establishment experiment, the residual effect of fenuron on white pine seedlings, and its effectiveness at a lower rate on various hardwoods were lnvestigated. Each hardwood stem over six feet tall was treated with one gram active fenuron in the spring of 1960. In March 1961, 100 white pine seedlings were planted in each of three plots previously treated. Five months after planting there was 99% survival of the pine seedlings. The one-gram rate was effective against red maple and the oaks but had little effect on sassafras, cucumber tree, and chestnut. Fenuron in some manner changed the composition of the plant community. Fireweed, poke, and several species of Panicum were present in the treated plots but were not present in the untreated buffer strips. / Master of Science
38

Influence of site factors and vascular conductivity on the development of procerum root disease

Butnor, John Robert 18 November 2008 (has links)
Procerum root disease (PRD) is a serious problem in eastern white pine (Pinus strobus L.) Christmas tree plantations in VIrginia. Procerum root disease is caused by Leptographium procerum (Kendr.) Wingf which is believed to be transmitted by the pales weevil Hylobius pales (Herbst). Symptoms of procerum root disease include reduced shoot elongation, reduced leaf conductance, low photosynthetic activity, low pre-dawn water potential and chlorosis of foliage. Resinous occlusion of the sapwood at the root collar is the likely cause of the suite of symptoms that resemble water stress. Increased incidence ofPRD has been associated with trees growing in poorly drained soils in low lying areas. Two studies were undertaken to explore the relationship of site factors and vascular conductivity of sapwood to the expression ofPRD symptoms in P. strobus. In the first study, plots were established in a variety of drainage classes in two Christmas tree plantations. Leaf conductance was monitored periodically in conjunction with measurements of soil factors to assess the role of abiotic factors on foliar symptom expression. At the termination of the field monitoring, trees were harvested and three vascular disease severity variables were measured: hydraulic conductivity of sapwood, percent basal occlusion and sapwood moisture content. These disease severity variables describe the permeability of sapwood to water and the relative hydration of the sapwood. Reduced leaf conductance was associated with reduced stem hydraulic conductivity, reduced sapwood moisture content and increased basal occlusion. Increased vascular disease severity and foliar symptom expression were associated with increased soil moisture content and several other factors that relate to soil moisture retention (percent slope, total porosity, textural class and bulk density). The second study was initiated to study the development of PRD in artificially inoculated P. strobus seedlings exposed to three soil water classes: droughty, optimum and saturated. Seedlings in the optimum soil water class exhibited the greatest biomass accumulation and shoot elongation, while seedlings in droughty showed the least. No negative effects of L. procerum inoculation and no symptoms ofPRD were observed eight months after inoculation regardless of the soil water class. / Master of Science
39

Root growth potential and bud dormancy of three northern pines with emphasis on eastern white pine

Johnsen, Kurt H. January 1985 (has links)
A two year study examined Root Growth Potential (RGP) in a hydroponic system and Dormancy Release Index (DRI) in one-year-old (1-0) and two-year-old (2-0) eastern white pine (Pinus strobus L.), red pine (Pinus resinosa Ait.), and Scotch pine (Pinus sylvestris L.) seedlings with emphasis on eastern white pine. During 1985-86 all three species of 2-0 stock displayed a similar pattern of RGP with high levels of RGP limited to mid-March. Only 2-0 eastern white pine had a statistically significant relationship between RGP and DRI; however, this relationship was not consistent in 1986-87. The RGP/DRI relationship in 2-0 eastern white pine was strong over both years within a DRI range of 0.22 to 1.00. One-year-old and 2-0 eastern white pine stock had very different patterns of RGP over both years with 1-0 stock maintaining much wider "lifting windows" for high RGP. Cold storage (2C) of 2-0 eastern white pine resulted in variable effects on RGP although it typically progressed dormancy release. There were no strong RGP trends between northern and southern provenances of 1-0 eastern white pine and heritability values indicate that RGP is under minimal genetic control in 1-0 eastern white pine seedlings. Northern and southern provenances did display clear differences in seedling morphology and seasonal patterns of shoot activity. Results of a field outplanting study show that RGP does show promise as a measure of 2-0 eastern white pine seedling quality. The predictive ability of RGP was increased on non-irrigated versus irrigated seedlings. A comparison of greenhouse versus growthroorn RGP testing demonstrated the validity of using greenhouse RGP testing of 2-0 eastern white pine. / M.S.
40

Physiological and morphological variation within and between populations of Suillus granulatus, as determined by mycorrhizal synthesis experiements

Jacobson, Kathryn Margaret 08 April 2009 (has links)
Mycorrhizal synthesis studies revealed that allopatric populations of Suillus granulatus differ in host specificity. Tissue cultures of Suillus granulatus used were from Nepal, (associated with Pinus wallichiana), Korea (Pinus densiflora) and the U.S. (Pinus strobus). Mycorrhizal effectiveness was used to measure host specificity. Useful characters for measuring mycorrhizal effectiveness were determined by ANOVAs between the uninoculated controls and mycorrhizal treatments. In addition, those characters which were stable within one population were determined via ANOVA. Useful characters, as defined by these two tests were: shoot wet weight, total wet weight, percentage mycorrhizal short roots, shoot dry weight, total dry weight and Hartig net penetration. These characters were subsequently used to measure variation in mycorrhizal effectiveness among the allopatric populations of Suillus granulatus. Isolates associated with Pinus strobus were most effective with Pinus strobus and least effective with the other trees, whereas isolates from Pinus wallichiana and Pinus densiflora showed variable effectiveness with all three trees. Phenetic analyses used to determine how similarly the isolates responded with the hosts confirmed these results. We conclude that isolates associated with Pinus strobus are most specific for this host, whereas isolates from the other two trees are not host specific. These results are discussed and hypotheses put forward to explain them. / Master of Science

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