Forest Sciences Commons^™

The Long-Term Effects Of Wildfire Severity On Oak-Pine Communities And Their Microclimates, Scott Glenn Culbert

Theses and Dissertations--Forestry and Natural Resources

In the eastern U.S., fire-dependent tree species have historically dominated upland forest communities, but are now experiencing widespread regeneration challenges as a result of 20^th century fire suppression policies, and are being replaced by mesophytic species. Wildfires that contain areas of high burn severity may provide an important means of mitigating these challenges and facilitating fire-dependent species regeneration and recruitment into larger size classes. One mechanism by which high-severity fire can accomplish this is by modifying understory microclimate characteristics to be more conducive to these species’ growth. A wildfire within the Daniel Boone National Forest, Kentucky, USA, provided the …

Regenerative Effects Of Patch Cut Harvests At Natchez Trace State Forest, Joshua K. Biggerstaff

Masters Theses

Patch cutting is a harvest method with very little precedent in the Central Hardwoods Region of the United States. It is defined as a small scale clearcut of 2 to 5-acres, and it is generally prescribed in order to lessen the aesthetic impact of harvesting in highly visible areas. This study examines a change in harvesting from clearcutting to patch cutting that occurred at Natchez Trace State Forest, located in west Tennessee, in the 1990s. The objective of the study was to determine the regenerative effects of the patch cuts 25-30 years later. Various patch-cut harvest units that were harvested …

The Effects Of Fire On Oak-Forest Plant Communities Along Soil Moisture Gradients: A 25-Year Study, Rebekah Frances Shupe

Theses, Dissertations and Capstones

In the eastern U.S., fire is a natural disturbance process in Quercus (oak) forests. Fire is thought to promote oak regeneration and plant diversity by reducing competition, preparing a suitable seedbed, and increasing light availability. However, the era of fire suppression that began in the early 20^th century is thought to have negatively impacted oak regeneration and the biodiversity of the understory layer. In this study, we examined the effects of prescribed fire on tree regeneration and the understory layer over 25 years. From a study initiated in 1994, we resampled 45 permanent vegetation plots measuring 1250 m^{2 …}

Understory Dynamics Across 62-Years Of A Northern Hardwood Management Gradient Study, Heidi Harmala

Dissertations, Master's Theses and Master's Reports

Northern hardwood selection silviculture relies on the perpetuation of natural regeneration. However, many researchers and forest managers have concerns about deficiencies in regeneration and the associated ingrowth and recruitment of advance regeneration under single-tree selection. Given the differences of management application in the Great Lakes region, long-term studies and datasets are critical to understanding of how these systems function and change. Using the Cutting Methods Study, in the Western Upper Peninsula of Michigan, these concerns were investigated with a multi-decadal dataset, for understory tree species composition and density, diversity, recruitment, and age-diameter relationships across management methods. In response to the …

Floodplain Forest Regeneration Dynamics In The Lower Mississippi River Alluvial Valley, Whitney Anne Kroschel

LSU Doctoral Dissertations

Floodplain forest species diversity is driven, in part, by variation in disturbance regime. Flood patterns create heterogeneity in microsite quality from small differences in elevation across a floodplain which, in turn, influence flood timing and duration. Differences in species’ regeneration niches in relation to hydrologic patterns can account for long-term coexistence of various species. In the past century floodplain forests have exhibited a wide range of changes in stand development and species composition as a result of altered hydrology in rivers and floodplains. I evaluated the role of regeneration in floodplain forest systems of the Lower Mississippi River Alluvial Valley …

Forest Structure Of Long-Term Conserved Areas Utilizing Different Strategies On A Continental, Glacial Moraine Formed Island, Christopher Coggin

Masters Theses, 2010-2019

Understanding patterns of forest succession can help advise management plans within New England nature preserves. This study took place on Block Island, 13 miles off the coast of Rhode Island. The island has greater than 200+ years of farming practices. After 1960, conservation groups began reforesting the island using different strategies, such as actively planting with native and exotic tree species, mowing, and preventing further development. In 2018, woody vegetation was inventoried along transects within four reforested sites. Sites were characterized as the following: actively planted with exotic and native tree species and mowed (AP-M), actively planted with exotic and …

Spatial And Temporal Patterns Of Invasive Exotic Plant Species In Response To Timber Harvesting In A Mixed Mesophytic Forest Of Eastern Kentucky, Benjamin Christopher Rasp

Theses and Dissertations--Forestry and Natural Resources

Invasive exotic species (IES) responses to silvicultural treatments eight years after timber harvesting were examined and compared to one-year post-harvest IES survey in University of Kentucky’s Robinson Forest. The temporal effects of harvesting were further compared between harvested and non-harvested watersheds. Analyses were performed to identify IES spatial distribution and determine the relationships between IES presence and disturbance effects, biological, and environmental characteristics. IES prevalence was higher in the harvested watersheds and was influenced by canopy cover, shrub cover and disturbance proximity. Ailanthus altissima and Microstegium vimineum presence in the study area has decreased over time. Comparing to the 1-yr …

Comparison Of Understory Chemical And Mechanical Treatments To Promote Regeneration Of Desirable Forestland Species, Rebecca Rachael Tyler

MSU Graduate Theses

Invasive woody plants and trees can have a negative impact on desired tree regeneration in the understory of forest stands, and forage density in grassland sites. An assessment of chemical and mechanical treatments on woody plants in the understory of forestland and in grassland is needed. Two experiments were set up in two forest stands and in two grassland/forest edge sites, with two treatment times during the growing season in the first year of the study. On the forestland sites, chemical and mechanical treatments were applied on undesired woody plants to see if they effect the regeneration of desired tree …

Growth Response Of Whitebark Pine (Pinus Albicaulis) Regeneration To Thinning And Prescribed Burn Release Treatments, Molly L. Mcclintock Retzlaff

Graduate Student Theses, Dissertations, & Professional Papers

Whitebark pine (Pinus albicaulis Engelm.) plays a prominent role throughout high-elevation ecosystems in the northern Rocky Mountains. It is an important food source for many birds and mammals, as well as a major player in high-elevation watershed maintenance, both slowing snowmelt and stabilizing soils. Whitebark pine is vanishing from the landscape due to three main factors – white pine blister rust (Cronartium ribicola) invasions, mountain pine beetle (Dendroctonus ponderosae) outbreaks, and successional replacement by more shade-tolerant tree species historically controlled by wildfire. In the past century, human activity such as fire suppression has altered these …

Effects Of Different Silvicultural Practices On Wild Turkey Brood Habitat And Regeneration In Upland Hardwoods, John Michael Mccord

Masters Theses

Optimum brood cover for wild turkeys is composed of herbaceous cover <0.5 m tall that conceals poults from predators and allows travel underneath. On tracts of hardwoods where early succession stages and young forest cover are scarce, a lack of understory development can limit turkey populations. Additionally, retaining oak on these sites after logging or habitat enhancement is important to provide future timber value and hard mast. I compared the effects of silvicultural practices (multiple fires [F], shelterwood cutting [S], shelterwood cutting with one fire [SF], retention cutting [R], retention cutting with multiple fires [RF], retention cutting with herbicide application [RH], and retention cutting with herbicide application and multiple fires [RHF]) with controls (C) on wild turkey brood habitat and oak regeneration in upland central hardwood stands. I measured structure and food resources to quantify the quality of wild turkey brood cover. Shelterwood and retention cuts increased photosynthetically active radiation. However, herbaceous, vine, and bramble groundcover did not increase. Woody regeneration was greater following canopy reduction and understory disturbance compared to C. Disturbance (fire or herbicide) was required to maintain vegetation at the ideal height for wild turkey broods. Soft mast production increased after canopy reduction with and without fire. Invertebrate biomass did not increase following any treatment, but availability exceeded the dietary requirements of a wild turkey brood. I also counted stem density of oak and competitor regeneration in response to these treatments. Seedlings <12.7 cm were ephemeral. S and SF had a greater density of oak stems >1.4 m than C and F. However, S and SF also had the greatest density of oak >1.4 m prior to treatment. Canopy reduction increased oak competitors, but prescribed fire reduced competitors. I recommend canopy reduction, followed by repeated low-intensity prescribed fire to maintain low groundcover to enhance brood habitat for wild turkeys in mature closed-canopy upland hardwood stands.

Managing Bushland On The Farm, Penny Hussey

Journal of the Department of Agriculture, Western Australia, Series 4

Since the time of European settlement in Western Australia, the replacement of native vegetation with crops and pastures has led to problems for both agricultural production and nature conservation. The most obvious of these are hydrological changes leading to salinisation and waterlogging, and the extinction of some native plants and animals.

Protection of remaining remnants of native bushland, together with revegetation, is increasingly seen as important ways of achieving sustainable agriculture and maintaining our unique wildlife.