Forest Sciences Commons^™

Practical Challenges In Delivering Dsrna For Woody Plant Protection, Zachary Bragg

Theses and Dissertations--Entomology

Unprecedented weather events associated with climate change, coupled with extensive anthropogenic stresses, have reduced the effectiveness of traditional forest pest management approaches, which can no longer keep pace with invasive species overwhelming naïve landscapes and native pests experiencing eruptive and expansive outbreaks. Double-stranded RNA-(dsRNA) mediated gene silencing, a type of RNA interference (RNAi), has been coopted for use as a biopesticide against a multitude of agricultural and horticultural pests and could serve as a powerful tool for woody plant protection. While effective initiation of gene silencing and subsequent mortality have been demonstrated in multiple tree pests, effective and efficient methods …

Effects Of Prescribed Fire On Planted Oak Growth And Survival In Restored Savannas, Allison Earl

Masters Theses

Most oak savannas in the Midwestern United States have been lost to agriculture and habitat degradation. Because of their rarity and ability to support high plant and animal diversity, savannas are often a target for restoration. Oak savanna restoration frequently relies on direct planting of oak seedlings to establish the necessary tree canopy. Returning fire to the system is critical to the herbaceous component of the savanna, but managers risk damaging or killing trees if burning is introduced too soon. I studied growth and physiological responses of three oak species (Quercus alba, Q. macrocarpa, and Q. velutina …

Antioxidant, Antidiabetic, And Antihypertensive Effects Of Peptides From Some Quercus Species, Muhammed Yusuf Çağlar, Muhammet Arici

Turkish Journal of Agriculture and Forestry

In the present study, the antihypertensive, antidiabetic, and antioxidant properties of oak peptides were determined in vitro. For this purpose, samples from most common oak species (Quercus coccifera, Quercus ilex, and Quercus cerris) were collected, the proteins were extracted and the bioactive properties of 48 different peptide fractions were monitored using a fast protein liquid chromatography. The results showed that acorn peptides had no remarkable antioxidant or antihypertensive effects. Comparing the bioactive peptides of all oak species, the peptides of Q. coccifera generally had higher DPP-IV inhibition activity than those of Q. cerris and Q. ilex. …

Prescribed Fire Alters Structure And Composition Of A Mid-Atlantic Oak Forest Up To Eight Years After Burning, Cody L. Dems, Alan H. Taylor, Erica A. H. Smithwick, Jesse K. Kreye, Margot W. Kaye

Aspen Bibliography

Background

Prescribed fire in Eastern deciduous forests has been understudied relative to other regions in the United States. In Pennsylvania, USA, prescribed fire use has increased more than five-fold since 2009, yet forest response has not been extensively studied. Due to variations in forest composition and the feedback between vegetation and fire, Pennsylvania deciduous forests may burn and respond differently than forests across the eastern US. We measured changes in forest structure and composition up to eight years after prescribed fire in a hardwood forest of the Ridge and Valley region of the Appalachian Mountains in central Pennsylvania.

Results

Within …

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 …}

Observable Persistent Effects Of Habitat Management Efforts In The Ozark Highlands After 10 Years, Maxwell Carnes-Mason

Graduate Theses and Dissertations

I investigated the lasting impacts of a management plan designed to improve oak regeneration and benefit wildlife in the Ozark Highlands in Madison, Co., AR. To assess the efficacy of the management plan, I used variables relevant to the success and establishment of oak trees. Controlled burns and selective logging were used to thin the canopy, increase ground level productivity, and increase the abundance of small mammals. I used measurements of overstory and understory densities, light availability, and the density of mice in the genus Peromyscus across time to look at the lasting impacts of management. Different treatment plots were …

Oaks (Family: Fagaceae) Diversity From Moist Temperate Forests Of Lesser Himalayas, Pakistan, Sher Wali, Kishwar Sultana, Fida Muhammad Khan

Journal of Bioresource Management

A detailed survey was conducted in five national parks and game reserves of Azad Jammu and Kashmir, Pakistan to assess the biodiversity of family Fagaceae. Identification of the species was done using literary sources and comparison of samples with herbaria from Quaid-i-Azam University, Islamabad and Pakistan Museum of Natural History, Islamabad, Pakistan. A total of eight different species belonging to two genera were identified, including Quercus spp., Castanea sativa, Quercus glauca, Quercus baloot, Quercus incana, Quercus velutina, Quercus alba and Quercus dilatata. The greatest biodiversity was found in Banjosa Game Reserve (BGR) and Tolipir National Park (TNP), while Pir …

Drought Stress Responses Of Seedlings Of Two Oak Species (Quercus Cerris And Quercus Robur), Ayşe Deli̇göz, Esra Bayar

Turkish Journal of Agriculture and Forestry

Effects of drought stress on growth, predawn xylem water potential (ψpd), osmotic solutes (soluble sugar and proline), and stomatal conductance were assessed in two oak (Quercus cerris L. and Quercus robur L.) seedlings. Seedlings of both species were subjected to three drought treatments with the following irrigation intervals: well-watered (control: irrigation every 2-3 days), moderate drought stress (irrigation every 15 days), and severe drought stress (irrigation every 30 days). Drought-stressed seedlings of Q. cerris and Q. robur had more negative predawn xylem water potential than their well-watered seedlings. In Q. cerris, root collar diameter and root dry weights were negatively …

Environmental And Soil Variables Affecting The Structure And Floristicwoody Composition Of Oak Forests Of Northeastern Mexico, Juan Antonio Encina-Domínguez, José Ramón Arévalo Sierra, Eduardo Estrada Castillon, Miguel Mellado Bosque

Turkish Journal of Agriculture and Forestry

The objective of this study was to investigate the influence of environmental and soil factors on the structure and floristic woody composition of oak forests. Oak forests of the Sierra de Zapalinamé in northeastern Mexico (25°N) are distributed in canyons and northwest slopes with higher humidity, surrounded by montane chaparral. We carried out a vegetation inventory across an altitudinal gradient. All trees with diameter at breast height of =>3 cm were identified and measured. In addition, the cover of understory species was measured in each plot. Using multivariate techniques, we detected two oak forest associations: Quercus greggii - Q. …

Dna Barcoding Of Quercus Falcata, Quercus Palustris, Quercus Rubra, And Their Hybrids Using Rbcl, Matk, And Ycf1, Mckinzie Johnson, Tim Trott

Research in Biology

No abstract provided.

Are Northeastern U.S. Forests Vulnerable To Extreme Drought?, Adam P. Coble, Matthew A. Vadeboncoeur, Z. Carter Berry, Katie A. Jennings, Cameron D. Mcintire, John L. Campbell, Lindsey E. Rustad, Pamela H. Temper, Heidi Asbjornsen

USDA Forest Service / UNL Faculty Publications

In the Northeastern U.S., drought is expected to increase in frequency over the next century, and therefore, the responses of trees to drought are important to understand. There is recent debate about whether land-use change or moisture availability is the primary driver of changes in forest species composition in this region. Some argue that fire suppression from the early twentieth century to present has resulted in an increase in shade-tolerant and pyrophobic tree species that are drought intolerant, while others suggest precipitation variability as a major driver of species composition. From this debate, an emerging hypothesis is that mesophication and …

Adaptive Variation And Introgression Of A Constans-Like Gene In North American Red Oaks, Jennifer F. Lind-Riehl, Oliver Gailing

Michigan Tech Publications

Oaks provide a model system to study maintenance of species identity by divergent selection since they maintain morphological differences and ecological adaptations despite interspecific hybridization. The genome of closely related interfertile oak species was shown to be largely homogeneous, with a few genomic areas exhibiting high interspecific differentiation possibly as result of strong divergent selection. Previously, a genic microsatellite was identified as under strong divergent selection, being nearly fixed on alternative alleles in the two interfertile North American red oak species: Quercus rubra L. and Quercus ellipsoidalis E.J. Hill. Further genotyping in two other red oak species—Quercus velutina Lam. and …

Context-Dependent Seed Dispersal By A Scatter-Hoarding Corvid, Mario B. Pesendorfer, T. Scott Sillett, Scott A. Morrison, Alan C. Kamil

Avian Cognition Papers

1. Corvids (crows, jays, magpies and nutcrackers) are important dispersers of large-seeded plants. Studies on captive or supplemented birds suggest that they flexibly adjust their scatter-hoarding behavior to the context of social dynamics and relative seed availability. Because many corvid-dispersed trees show high annual variation in seed production, context-dependent foraging can have strong effects on natural corvid scatter-hoarding behavior.

2. We investigated how seed availability and social dynamics affected scatter-hoarding in the island scrub jays (Aphelocoma insularis). We quantified rates of scatter-hoarding behavior and territorial defense of 26 colormarked birds over a three-year period with variable acorn crops. …

Genetic Variation, Local Adaptation And Population Structure In North American Red Oak Species, Quercus Rubra L. And Q. Ellipsoidalis E. J. Hill, Jennifer F. Lind-Riehl

Dissertations, Master's Theses and Master's Reports - Open

Forest trees, like oaks, rely on high levels of genetic variation to adapt to varying environmental conditions. Thus, genetic variation and its distribution are important for the long-term survival and adaptability of oak populations. Climate change is projected to lead to increased drought and fire events as well as a northward migration of tree species, including oaks. Additionally, decline in oak regeneration has become increasingly concerning since it may lead to decreased gene flow and increased inbreeding levels. This will in turn lead to lowered levels of genetic diversity, negatively affecting the growth and survival of populations. At the same …

Effects Of Midstory Removal And Shoot Clipping On The Growth And Development Of Three Oak Species, Jared Matthew Craig

Theses and Dissertations--Forestry and Natural Resources

Problems developing tall oak seedlings of high abundance have become a concern throughout many eastern hardwood forests. The decline in oak seedling recruitment into canopy positions is often attributed to the increasing abundance of shade tolerant midstory species, especially red maple (Acer rubrum L.). Studies have shown that increasing light to the understory by way of a midstory removal has the ability to favor oak seedlings over competitors. The majority of studies to date have examined northern red (Quercus rubra L.) and cherrybark oak (Quercus pagoda Raf.) on productive sites, but relatively little is …

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.