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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.
1

Wood quality studies in second-growth western redcedar (Thuja plicata Donn.) /

DeBell, Jeffrey D. January 1998 (has links)
Thesis (Ph. D.)--Oregon State University, 1999. / Typescript (photocopy). Includes bibliographical references (leaves 78-82). Also available on the World Wide Web.
2

Influence of eastern redcedar (Juniperus virginiana L.) on soil properties and vegetative composition of a sand prairie in southwestern Wisconsin

McBain, Donna K. January 1983 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1983. / Typescript. eContent provider-neutral record in process. Description based on print version record.
3

A study of the soluble carbohydrate materials isolated from the western red cedar, Thuja plicata

Rosenbaum, Seymour Leonard, 1921- January 1943 (has links)
No description available.
4

Isolation and characterization of actively anabolized dilignol rhamnosides in the leaves of western red cedar (Thuja plicata donn)

Manners, Gary Duane January 1970 (has links)
Three dilignol rhamnosides were isolated in 0.15 to 0.40% yield from the ethyl acetate solubles of a methyl alcohol extract of western red cedar (Thuja plicata Donn) leaves using silicic acid and Sephadex LH-20 pressure column chromatography. One of the three dilignol rhamnosides was characterized as l-(3'-methoxy-4'-hydroxyphenyl)-2-0-l"-[2"-hydroxy-4"-(propane-3"'-α-L-rhamnoside)phenyl]-propane-l,3 diol, using NMR and chemical degradation in conjunction with mass spectral techniques on the compound and its derivatives. The other dilignol rhamnosides were not completely characterized, but were shown to be chemically related to the dilignol identified. Based upon NMR, chemical and mass spectral data, the uncharacterized dilignol rhamnosides are speculated to contain phenylcoumaran and guaiacyl benzdioxane structures. The characterized dilignol rhamnoside represents the first reported occurrence of a free dilignol glycoside in plant tissues. The unusual α-L-rhamnose moiety of the dilignol occurs in a previously unreported linkage to the n-propyl hydroxyl group uncommon in lignin. The rhamnoside also displays the previously unreported guaiacylglycerol-catechol-β-aryl ether structure rather than the commonly observed guaiacylglycerol-guaiacyl-β-aryl ether structure. A new combustion-absorption technique was developed and validated which allows high efficiency evaluation of low activity radioactive products separated on thin layer cellulose chromatography plates. The technique was applied to an analysis of the anabolic products of an infusion feeding of U- (14)C--L-phenylalanine to western red cedar leaves. Facile imbibition of U-(14) C-L-phenylalanine occurs within ten hours. Maximum incorporation of 0.30%. and 0.40% of the available radioactivity occurs in the characterized dilignol rhamnoside, and its suspected phenylcoumaran homolog respectively, at the three to five hour period of the infusion feeding. The incorporation results indicate the participation of the dilignol rhamnosides in aromatic metabolism in the leaves of western red cedar. This feeding experiment is preliminary to future detailed biosynthetic studies in the leaf tissue. The combustion-absorption technique is limited to combustible sample weights of 7 mg. / Forestry, Faculty of / Graduate
5

The use of remotely sensed LiDAR and multispectral imagery for modeling eastern redcedar biomass within North Eastern Kansas

Bryant, Johnny January 1900 (has links)
Master of Arts / Department of Geography / Kevin P. Price / Due in large part to changes in land management practices, eastern redcedar (Juniperus virginiana L.), a native Kansas conifer, is rapidly invading onto valuable rangelands. The suppression of fire and increase of intensive grazing, combined with the rapid growth rate, high reproductive output, and dispersal ability of the species have allowed it to dramatically expand beyond its original range. Based on its abundance and invasive nature there is a growing interest in harvesting this species for use as a biofuel. For economic planning purposes, density and biomass quantities for the trees are needed. Three methods are explored for mapping eastern redcedar and quantifying its biomass in Riley County, Kansas. First a comparison of plot-regression versus individual tree based techniques is conducted to determine the optimal approach for characterizing redcedar tree canopy using LiDAR (Light Detection and Ranging). Second a hybrid approach is utilized to characterize redcedar canopy biomass using LiDAR and high-resolution multispectral imagery. Finally, to explore alternative methods of characterizing the three-dimensional structure of redcedar canopy a comparison of “Structure from Motion” photogrammetric techniques and LiDAR is conducted. These methods showed promising results and proved to be useful in the forestry, range management, and bioenergy industries for better understanding the potential of invasive redcedar as a biofuel resource.
6

Climatic and edaphic influences on the radial growth of eastern redcedar (Juniperus virginiana), Smoke Hole Canyon, West Virginia

Wixom, Joshua A. January 1900 (has links)
Thesis (M.A.)--West Virginia University, 2009. / Title from document title page. Document formatted into pages; contains vi, 67 p. : ill. (some col.), col. maps. Includes abstract. Includes bibliographical references (p. 39-42).
7

Detoxification of thujaplicins in living western redcedar (Thuja plicata Donn.) trees by microorganisms

Jin, Lehong January 1987 (has links)
Thujaplicins are the major components in the steam-volatile fraction of western redcedar (Thuja plicata Donn.) (WRC) heartwood extractives. They are consided to be highly toxic to fungi and are chiefly responsible for WRC heartwood decay resistance. This study proves that this traditional concept of toxicity is not completely correct. Thujaplicins are toxic to common decay fungi isolated from decayed WRC wood in living trees or wood in service, such as Poria albipelIucida Baxter. On the other hand, when a fungus such as Sporothrix sp. invades sound heartwood of living WRC, thujaplicins do not provide resistance but instead are altered by that fungus, so that their toxicity to decay fungi is destroyed. Evidence obtained in this study indicates that the mechanism of thujaplicin toxicity to common decay fungi involves the reactive keto-enolic group. As example, thujaplicin toxicity disappears if this reactive group is blocked by laboratory methylation. In living trees detoxification by Sporothrix sp. is demonstrated to involve a process of oxidative dimerization and isomerization of the thujaplicins to a new lactone compound. This compound is proven to have no toxicity to decay fungi, such as Poria albipelIucida Baxter. The dimerization and isomerization destroy the reactivity of the keto-enolic group and thus thujaplicin toxicity. Isolation, purification, and determination of the chemical structure of the new lactone compound produced from thujaplicins during Sporothrix sp. infection was carried out by chemical, chromatographic and spectroscopic methods. This naturally occurring compound has not been isolated previously and there are no previous reports in the literature about a compound with this structure. Following IUPAC rules, the compound is named as 3,3,4,7,7,8-hexamethyl-2,6-dioxa-1,5-anthracene-dione, and given the trivial name 'Thujin'. Biological experiments carried out in this study clearly show that in living WRC trees, fungal attack involves a succession of microorganisms. Three early stage attacking fungi were consistantly isolated from discolored WRC heartwood. They are identified as Sporothrix sp. KirschsteinieIIa thujina (Peck) Pomerleau & Etheridge and Phialophora sp. Biological roles of these fungi are demonstrated based upon the results of wood block bioassays and chemical analysis of wood blocks treated with the three fungal isolates. / Forestry, Faculty of / Graduate
8

Ecophysiological assessment of western hemlock and western red cedar greenhouse stocktypes

Major, John E. January 1990 (has links)
Western hemlock (Tsuga heterophylla (Raf.) Sarg.) and western red cedar (Thuja plicata Donn) seedlings from four dormancy induction treatment(s) (DIT) (i.e. long-day dry, long-day wet, short-day dry, and short-day wet) were planted on a high available soil moisture field site in British Columbia and monitored for physiological response and morphological development over the first growing season. Stomatal conductance (gwv) and net photosynthesis (Pn) were recorded over an environmental matrix of photosynthetically active radiation (PAR) (0 - 2.2 mmol m⁻² s⁻¹ ) and vapour pressure deficit (VPD) (0 - 2.5 or 4.0 kPa) on both first year grown and fully developed second year foliage. To compare stocktypes, physiological data were collected and analyzed in the following ways: (1) replicated data at stable environmental conditions once a month, (2) physiological response to one increasing environmental variable using boundary line analysis, and (3) physiological response surface to two simultaneously changing environmental variables. For western hemlock first year needles, short-day DIT had a higher gwv response to both increasing VPD and PAR. Both short-day and moisture stressed DIT improved Pn response to PAR, and the combination had the highest response. Short-day DIT seedlings initially were smaller, shorter, had a better seedling water balance ratio and lower shoot to root ratio. Short-day second year needles showed a slightly higher gwv response to both increasing VPD and PAR as compared to long-day seedlings; however, they showed no treatment differences for Pn versus PAR. All stocktypes had similar final morphological parameter values. For western red cedar first year foliage, moisture stressed DIT seedlings had greater Pn response to increasing PAR and VPD. Also, moisture stressed seedlings gwv response to increasing VPD and PAR was higher when compared to its' non moisture stressed daylength counterpart. The long-day wet seedlings initially had a larger root and shoot system as compared to the other stocktypes. Second year foliage exhibited no treatment differences for gwv and Pn response to PAR ' and VPD. All stocktypes had similar final morphological parameter values. Attempts to test stocktypes at stable environmental conditions proved, at times, difficult. Potentially large measurement variation due to atmospheric environmental changes, and not stocktype effect, could result. Boundary line analysis, when used correctly and with sufficient data, offers a good stocktype assessment method which enables the isolation of a physiological response to one environmental variable. Three dimensional surface response technique was required to provide a clear conceptual representation of two primary environmental variables' influence on seedling physiological response. / Forestry, Faculty of / Graduate
9

Hydroclimate reconstructions of the Potomac River Basin using tree rings

Maxwell, Richard Stockton. January 1900 (has links)
Thesis (Ph. D.)--West Virginia University, 2010. / Title from document title page. Document formatted into pages; contains vii, 102 p. : ill. (some col.), maps (some col.). Vita. Includes abstract. Includes bibliographical references.
10

The study of the effect of an alkaline pulping catalyst derived from plicatic acid /

Fong, Jenny L. January 1986 (has links)
No description available.

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