Treesearch

Regeneration of oaks is a priority for most landowners in the south given their inherent wildlife benefits, economic return, ascetics, and providing habitat for endangered species. In the case of natural disasters such as Hurricane Katrina artificial regeneration of these stands may be the only viable option to reestablish an overall oak component in a future stands overstory. This study evaluated growth of two oak species, water oak (Quercus nigra) and swamp chestnut oak (Quercus michauxii), and three planting stocks: 1-0 bareroot, conventional containerized, and EKOgrownTM seedlings were...

Management efforts on public lands across the southern Appalachian Mountains are increasingly focused on the creation, maintenance, and/or restoration of resilient structures and species compositions, with prescribed burning being the primary tool by which many of these restoration efforts are conducted. In this study, we use regeneration data from a study designed to examine the ecosystem response of upland hardwood forests to prescribed burning in western North Carolina. Four 5-ha productive mixed-hardwood stands were burned between 2009 and 2010. Five years following the first burn...

Oak (Quercus) is difficult to naturally regenerate in many mature oak stands on productive sites in the southeastern United States, and artificial regeneration alternatives should be considered. Artificial regeneration can potentially restore or enrich the oak component at the stand level. We examined genetic and silvicultural effects on artificially regenerated northern red oak (Quercus rubra) seedlings three years after planting under three silvicultural prescriptions and a control. We used quality-grown seedlings from openpollinated families to improve probabilities of success. The...

Context. No single model can capture the complex species range dynamics under changing climates--hence the need for a combination approach that addresses management concerns. Objective. A multistage approach is illustrated to manage forested landscapes under climate change. We combine a tree species habitat model--DISTRIB II, a species colonization model--SHIFT, and knowledgebased scoring system--MODFACs, to illustrate a decision support framework. Methods. Using shortleaf pine (Pinus echinata) and sugar maple (Acer saccharum) as examples, we project suitable habitats under two future...

The conversion of agriculture lands to forest has been occurring in parts of North America for decades. The legacy of management activity during this transition is reflected in soil physical and chemical properties years after abandonment. This study was conducted at the Smithsonian Environmental Research Center, Maryland, USA, to determine land-use history and forest age effects on soil nutrients, carbon, pH, and bulk density. Soils in young and old successional forests and forests with no evidence of historical disturbance were sampled. The young forest stands were abandoned from...

A long-term assumption in ecology is that species distributions correspond with their niche requirements, but evidence that species can persist in unsuitable habitat for centuries undermines the link between species and habitat. Moreover, species may be more dependent on mutualist partners than specific habitats. Most evidence connecting indigenous cultures with plant dispersal is anecdotal, but historical records suggest that Native Americans transported and cultivated many species, including Gleditsia triacanthos ("Honey locust"). Gleditsia triacanthos was an important medicinal/culinary...

Mangroves are well-known for their numerous ecosystem services, including sequestering a significant carbon stock, with soils accounting for the largest pool. The soil carbon pool is dependent on the carbon content and bulk density. Our objective was to assess the spatial variability of mangrove soil physical and chemical properties within the Zambezi River Delta and determine whether it may be associated with geomorphic setting. Plots were classified as one of four geomorphic settings: seaward fringe, creek, riverine, and interior. Additionally, we attempted to determine the source(s) of...

Tropical wetland ecosystems, especially mangroves and peatlands, are carbon (C) rich ecosystems. Globally, tropical mangroves store about 20 PgC, however, deforestation has contributed 10 % of the total global emissions from tropical deforestation, even though mangroves account for only about 0.7 % of the world’s tropical forest area (Donato et al. 2011). Meanwhile, tropical peatlands store 191 PgC or approximately 33 % of global peatland C (Post et al. 1982; Page and Rieley 1999). This disproportionate capacity of tropical wetlands to sequester and store C make them a critical component...

Oaks (Quercus spp.) grown in monoculture plantations often do not develop high-grade boles because all the trees grow at similar rates and crown stratification does not occur resulting in persistent branches and poor bole quality. The use of trainer species in mixed species plantations could promote interspecific competition and crown stratification leading to higher grade oak boles. As part of a larger, long-term study investigating growth, crown interactions, and bole development of cherrybark oak (Quercus pagoda) with several species at different planting densities, yellow-poplar...

Climate change and forest disturbances are threatening the ability of forested mountain watersheds to provide the clean, reliable, and abundant fresh water necessary to support aquatic ecosystems and a growing human population. Here we used 76 years of water yield, climate, and field plot vegetation measurements in six unmanaged, reference watersheds in the southern Appalachian Mountains of North Carolina, USA to determine whether water yield has changed over time, and to examine and attribute the causal mechanisms of change. We found that annual water yield increased in some watersheds...