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.

Timber and wildlife habitat management may be conflicting objectives, but both benefit from increasing light in bottomland forests through harvesting and midstory control, and a target residual basal area may be used to optimize both. Six areas were used to evaluate effects of partial harvest and midstory control on oak regeneration, diameter growth of residual trees, and white-tailed deer carrying capacity. Partial harvest treatments consisted of residual basal areas of 70ft2/ac (16.07m2/ha), 60ft2/ac (13.77m2/ha), 50ft2/ac (11.48 m2/ha), 40ft2/ac (9.18m2/ha), 30ft2/ac (6.89m2/ha), and untreated controls. All partial harvest areas received midstory control using injection with imazapyr. Available light was related to residual basal area (R2 = 0.808). Treatments with 50ft2/ac residual basal area exhibited the optimal amount of oak regeneration and white-tailed deer carrying capacity. Treatments with 30ft2/ac had greatest diameter growth. This research provided guidelines for managers that wish to optimize white-tailed deer habitat and oak regeneration.

No description available.

Hurricane Katrina made landfall in 2005 damaging 1.2 billion cubic meters of timber including 48 million cubic meters of hardwood. An economically efficient method of artificial oak regeneration is necessary in many areas to restore this high value resource. Bareroot, conventional containerized, and EKOgrown® seedlings of Quercus shumardii and Q. texana were planted on two sites in south Mississippi. Growth and survival were evaluated for two years. Survival was assessed monthly and at the end of each growing season. Height and groundline diameter were assessed initially after planting and the end of each growing season. After two growing seasons, Q. Nuttallii exhibited superior performance generally when compared to Q. Shumardii. Conventional containerized had poor survival and initial growth likely caused by freeze damage in the nursery. EKOgrown® seedlings performed better than other planting stocks, however, high seedling cost makes them less cost-effective than bareroot seedlings which exhibited acceptable performance overall.

The regeneration in oak-dominated stands following five silvicultural treatments was examined on four sites in the mountains of Virginia and West Virginia. Treatments included: silvicultural clearcut, leave-tree, commercial clearcut, shelterwood, and group selection. The effects of harvesting were compared among sites and among treatments. Oak regeneration dominance, measured by the relative density of dominant and codominant oak regeneration, was the most important variable calculated from the data. Oak regeneration dominance varied by site, but did not vary by silvicultural treatment; all treatments resulted in relatively low numbers. Therefore, the silvicultural treatments used here were not enough to overcome the site specific limitations to successful oak regeneration. Oak species also seemed to be less important in the regenerating stands than in their parent stands. The biggest losses in oak importance occurred on the intermediate and high quality sites; competitive oak regeneration was relatively scarce on two of the three sites with an oak site index (base age 50) of over 70 ft. Multiple linear regression analysis was used to identify the factors controlling oak regeneration at a smaller scale. The most important variables were those that described the oak stump sprouting potential, the understory and overstory oak component in the pre-harvest stand, post-harvest light and soil nitrogen levels. / Master of Science

Patch clearcutting can be put to effective use for landowners with relatively small stands of timber. This project was designed to determine how clearcut opening size and mid-rotation crop tree release affects the value and volume of sawtimber at the end of rotation. In 1960 patch clearcuts were established in three different diameters, 50ft (.05ac), 150ft (.41ac), and 250ft (1.13ac). Current stand data (2011) was collected to determine trees per acre, basal area, average tree diameter, volume, and value. These data were input into a growth simulator to determine future trees per acre, basal area, average tree diameter, volume, and value with a crop tree release treatment and a control to 2061. The 50ft openings yielded little merchantable volume at mid-rotation and were primarily composed by shade tolerant species. In the 150ft and 250ft openings, there was better species diversity and an increase in sawtimber volume and value. Using openings of 150ft or greater, landowners can regenerate commercially important species and manage their forests to produce valued timber and maintain aesthetics.

<p>  </p> <p>Alterations to the historic fire regime have contributed to widespread regeneration failure in <em>Quercus</em> L. (oak) forests of the eastern United States. Composition has shifted from <em>Quercus</em> and other fire-adapted species to dominance by mesophytic species. While land managers often focus efforts on restoring <em>Quercus</em> regeneration, the herbaceous layer experiences reduced cover and diversity of herb and graminoid species resulting from the increased woody stem density in fire-suppressed forests. Declining abundance of <em>Quercus</em> species and diversity in the herbaceous layer reduce the overall habitat quality and ecosystem functions provided by the forest. A combination of overstory harvests and prescribed burning are often conducted to restore the plant community in <em>Quercus</em> forests affected by mesophication. Initiated in 2010, our study on the Hoosier National Forest in Indiana conducted shelterwood and midstory (mechanical, chemical, or none) harvests followed by prescribed burning on a less productive site, while leaving a more productive site unburned. Our objective was to evaluate the survival and competitive response of <em>Quercus</em> spp. within the regeneration layer and whether diversity and cover increased in the herbaceous layer following treatments. Using nested circular plots, we measured seedling survival and resprout response, in addition to regeneration density before and after treatments. We measured the percent cover of herbaceous-layer species within quadrats and calculated species richness, evenness, and diversity. Using multiple mixed-effects models, ANOVA, and NMDS ordination, we evaluated woody species regeneration and herbaceous-layer composition before and after treatments. Post-treatment, monitored <em>Quercus</em> spp. seedlings at the burned site displayed greater survival (> 94%) and resprouting (> 92% of monitored stems), which exceeded most competing species, including<em> Acer</em> spp. (~ 59% survival and resprouting) and <em>Fraxinus americana </em>(72% survival and resprouting). <em>Q. alba</em> seedling (< 3.8 cm DBH) densities doubled after burning; it was one of the most abundant species (9,864 stems ha-1) at the burned site. NMDS ordination indicated a clear shift in regeneration species composition with the burn driving a shift away from mesophytic species towards greater importance of <em>Quercus</em> species. Additionally, our burned site had significantly increased herbaceous-layer richness, Shannon diversity index, and total cover compared to pre-treatment. Percent cover increased across all plant functional groups within the herbaceous layer, with trees/shrubs exhibiting the greatest increase. Herbaceous-layer composition at the burned site significantly shifted toward greater importance of graminoids and herbs post-treatment. Post-treatment, the unburned site contained fewer, and less competitive, <em>Quercus</em> seedlings compared to non-<em>Quercus</em> competitors and displayed no significant compositional shifts in seedling species composition post-harvest. Our unburned site exhibited significant, but minor, increases in herbaceous-layer richness, evenness, diversity, and total cover. Herbaceous-layer composition at the unburned site was significantly different post-treatment, shifting towards greater importance of vines, trees/shrubs, and herbs. The more-productive unburned site would likely require multiple burns to produce adequate competitive <em>Quercus</em> seedlings to perpetuate dominance in the developing stand. Burning would also likely result in greater increases in herbaceous-layer diversity compared to harvesting alone. Conversely, the shelterwood, followed by a single burn, on the less productive site had a more substantial effect on the herbaceous layer, and likely produced an adequate density of <em>Quercus</em> reproduction to ensure future dominance by the genus.</p>

Bare-root, container, and root production method (RPM™) seedlings of two oak species (Nuttall (Quercus texana Buckley), cherrybark (Q. pagoda Ell.)) were planted on lands damaged by Hurricane Katrina in southern Mississippi to compare the height growth, groundline diameter growth and survival of the different planting stocks. Tree shelters were applied to half of the bare-root seedlings to determine their effect on the height and groundline diameter growth and survival of the seedlings. RPM seedlings exhibited significantly greater height and groundline diameter growth than bare-root or container seedlings after one growing season. Bare-root seedlings exhibited significantly greater height and groundline diameter growth than container seedlings. Tree shelters significantly increased height growth of bare-root seedlings; however, sheltered bare-root seedlings exhibited significantly less groundline diameter growth than non-sheltered seedlings. Cherrybark oak exhibited greater height growth than Nuttall oak, while Nuttall oak exhibited greater groundline diameter growth than cherrybark across all planting stocks.