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EFFECTS OF MIDSTORY REMOVAL ON BLACK OAK (<i>QUERCUS VELUTINA</i>) AND WHITE OAK (<i>QUERCUS ALBA</i>) REGENERATIONParrott, David Lee 01 January 2011 (has links)
The formation of dense understories in eastern forests has created low light environments that hinder the development of advance oak reproduction. Studies have shown that a midstory removal can enhance these light conditions and promote the development of competitive oak seedlings. Previous studies have been primarily focused on oaks found on productive sites, and there is little knowledge of this treatment’s potential on intermediate sites and the typically associated oak species. This study investigates the seven-year effects of midstory removal on natural and underplanted white (Quercus alba L.) and black oak (Quercus velutina L.) reproduction, as well as competing red maples (Acer rubrum L.), on intermediate sites within the western rim of the Cumberland Plateau. In addition to its effect on stand reproduction, this study also investigates the impact of this treatment on microclimate. Results from this study can provide a look at the long term success of midstory removal on intermediate quality sites and serve as a basis for future oak management in the region.
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Seed Production and Seed Quality in Red Maple (Acer rubrum L.)Goszka, Abigail R. 20 September 2019 (has links)
No description available.
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Growth of Clonal Red Maples on Varying Site Conditions in Mississippi and Response to Pneumatic Fracturing and Liquid InjectionFulgham, David Tildon 03 May 2019 (has links)
Trunk height, diameter, and stomatal conductance measurements were taken over a three-year time frame on clonal red maple cultivars [Acer rubrum ‘Frank Jr’] on two sites with varying conditions. Physiological and morphological effects on tree growth were measured on both sites in response to Pneumatic Fracturing (PF) and Liquid Injection (LI) treatments. The primary questions asked in study one were: (1) Does stomatal conductance differ among the two sites during mid-summer? and (2) Do height and diameter measures differ among the two sites? In study two, I asked: (1) Do height, diameter and stomatal conductance differ between site modification treatments within each site? Control samples on the Site 2 had significantly more growth than the controls on the Site 1. PF and LI treatments showed significantly more diameter growth on the Site 1 while a significant difference was also seen in stomatal conductance following treatments on Site 1.
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Changes in freezing tolerance, abscisic acid concentraion, and gene expression during cold acclimation of Acer rubrum fine roots /Borden, Melissa L. 01 January 1999 (has links) (PDF)
No description available.
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Isolation and Characterization of a Suspected Phytoalexin from Wilted Red Maple LeavesBaisden, Jared T. January 2013 (has links)
No description available.
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Oak regeneration: Impacts of prescribed fire and invasive speciesGoldsmith, Caleb Desmond 06 August 2021 (has links)
Across the central and eastern United States, upland oaks are experiencing regeneration complications. This thesis comprises two studies evaluating challenges in regenerating upland oaks. One study evaluates upland Quercus spp., Carya spp., and Acer rubrum L. response to prescribed fire and impacts on seedling growth and mortality. This study found prescribed fire promoted oak growth when canopy cover was < 77%. Oaks displayed lower percent mortality and higher resprout capacity after fire compared to red maple. The second study investigates impacts of Microstegium vimineum presence on Quercus alba L., Liriodendron tulipifera L., and Acer rubrum L. seedlings under different light and moisture environments. Microstegium vimineum presence decreased growth of both sweetgum and red maple; white oak was less impacted, likely because of its conservative growth strategy and high-water use efficiency. Oaks’ conservative growth strategy may offer more resiliency compared to its competitors in response to prescribed fire and Microstegium vimineum.
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The Effects of Soil Phosphorus on <i>Acer rubrum</i> FecundityPeters, Anna L. 11 June 2014 (has links)
No description available.
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Influences of elevated atmospheric CO₂ and water stress on photosynthesis and fluorescence of loblolly pine, red maple, and sweetgumLenham, Philip J. 23 June 2009 (has links)
Changes in light harvesting ability and other physiological responses could int1uence the competitive outcomes of tree species in a future elevated CO₂ atmosphere. Photosynthetic light response curves were constructed with a closed photosynthesis system (LI-COR, Inc. Lincoln, NB) in order to investigate the effect of growth in elevated CO₂ (746 μl⁻¹) and ambient CO₂ (379 μl⁻¹) on light responses, and seedlings were allowed to dry out to examine physiological changes to water stress. While drying out, photosynthesis was measured with a closed system (LI-COR, Inc. Lincoln, NB) and fluorescence was measured with a portable fluorescence measurement system (P.K. Morgan Instruments, Inc Andover, MA). No species showed significant increases In quantum yields or decreases in light-compensation points as a result of elevated CO₂. Photosynthesis declined in all species due to water but seedlings grown in elevated C0₂ maintained photosynthesis longer. Loblolly pine and red maple grown in e1evated CO₂ showed signs of photosynthetic acclimation. Photochemical efficiency of PSII declined with water stress in loblolly pine. Red maple and sweetgum showed no relationship between photochemical efficiency of PSII and simulated drought. Growth in elevated C0₂ did not influence this response in loblolly pine, but sweetgum started with a lower photochemical efficiency or PSII which increased significantly. / Master of Science
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The Importance of Dissolved Organic Matter Source on the Survival and Growth of Juvenile DaphniaWilkins, Keiko W. 18 January 2020 (has links)
No description available.
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Expanding Markets and Industrial Practices for Thermally Modified WoodGonzalez, Juan Jose 19 June 2020 (has links)
Thermally modified wood (TMW) contains no toxic components and is recommended for its durability, levels of equilibrium of moisture content, and dimensional stability performance. A limitation of TMW is the lack of market acceptance and products due to insufficient information regarding the performance of commercially available products. The goal of this project was to improve the market penetration and industrial processes of TMW. The first objective was to study the perception of TMW products from architects in North America using a survey instrument. Results revealed that information regarding TMW is not reaching the audience for TMW, and that providing knowledge regarding technical and marketing aspects of TMW is essential to increase the market share. The second objective consisted of the evaluation of the variability of the physical and mechanical properties of three thermally treated species manufactured in North America. Results showed that the performance of the commercially produced material was similar among the three companies, where only in seven out of 24 properties had statistical differences. Properties that were significantly different, did not have large enough differences in means to be realistically noticed by customers and all were highly different from untreated wood. The final objective involved the implementation of Lean thinking to the manufacturing process of TMW with the goal of improving the process with a direct impact on cost and waste reductions. Three companies were used as case studies for the production process. The implementation of Lean thinking in the process proposed a reduction in lead times from 55.47 days to 23.20 days, with an increase in value-added activities from 1% to 6%. Most of these gains were obtained through a reduction in inventory levels. / Master of Science / Thermally modified wood (TMW) contains no toxic components and is recommended for its durability, levels of equilibrium of moisture content, and dimensional stability performance. The current market for TMW encounters a lack market acceptance, due to insufficient information and performance measures. The main goal of this study was to increase market penetration and study the industrial processes for manufacturing TMW, using three specifics objectives.
For the first objective, a survey was conducted to study the perception of TMW among architects. The results showed a that there was a lack of information regarding the technical and marketing aspects of TMW products, which needs to be addressed by distributors and producers.
The second objective consisted of the evaluation of the variability of mechanical and physical properties of three thermally treated species manufactured in North America. The results showed that the performance from the commercial processes were similar, where only seven out of 24 cases showed statistical differences based on the Analysis of Variance (ANOVA).
The final objective consisted of a Lean process strategy to produce TMW, improving the process with a direct impact on cost and waste reduction. To study the production process, three case study companies were used. The proposed Lean process reduced the lead times and value-added activities increased. The primary gain was seen in reducing inventory levels.
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