Treesearch

Juglans cinerea L. (2n = 16), commonly known as butternut, is a diploid species native to the eastern forests of the United States and Canada. It plays a crucial ecological role as a food source for wildlife and is traditionally used as a medicine by tribal communities. Butternut populations have severely declined over 50 years due to butternut canker disease (BCD). The ability of butternut to hybridize with Japanese walnut, which exhibits resistance to BCD, complicates hybrid identification based on morphological traits alone. In this study, we assembled the chloroplast genome of butternut...

Butternut (Juglans cinerea L.) is a rapidly declining tree species threatened by Ophiognomonia clavigignenti-juglandacearum (Oc-j), the causal agent of butternut canker. The introduction of Japanese walnut (Juglans ailantifolia Carrière), which hybridizes with butternut and exhibits greater resistance to the disease, presents both a conservation challenge and a potential avenue for genetic improvement. Identifying non-admixed butternuts is critical for conservation efforts and breeding programs aimed at preserving the species’ genetic integrity while exploring resistance strategies....

The environmental suitability of a particular organism is often a combination of local climatic factors, resource competition intensity, as well as pathogen and predator pressure. Pathogen pressure, or host resistance, is particularly important in host species severely impacted by disease. Variations in heritable pathogen resistance can lead to differences in apparent habitat suitability of resistant or susceptible subpopulations. In the case of the butternut tree (Juglans cinerea), habitat suitability is limited by genetic resistance to the non-native butternut canker disease (BCD) in...

Tree of heaven [ Ailanthus altissima (Mill.) Swingle] is an invasive tree that inhibits regeneration of forests. Management of forests invaded by A. altissima often includes chemically treating it and leaving dead boles behind. Verticillium wilt ( Verticillium nonalfalfae ) infects some populations of A. altissima , leading to localized mortality. Areas with population-wide A. altissima mortality may increase as this disease spreads or is used as a biocontrol agent. Ailanthus altissima has documented allelopathic compounds; stems left to decompose may result in soil legacy effects that...

Stress from low light availability and flooding can reduce photosynthesis and growth rates of trees, contributing to possible regeneration challenges in bottomland hardwood forests. This study investigated the photosynthetic light responses of pin oak (Quercus palustris Muenchh.) and swamp white oak (Quercus bicolor Willd.) seedlings growing in two light environments and across a hydrological gradient. Our findings revealed that neither light environment nor soil moisture availability had a significant impact on leaf mass per area, light compensation point, dark respiration rate, or...

For over a century, economic ideas have shaped US public land management. This culminated with ‘maximum sustainable yield’ (MSY) becoming a central decision-making framework. However, the passage of major environmental legislation—echoing an American preservationist tradition—spurred the US Forest Service and other public agencies to reconsider this narrow utilitarian approach, setting the stage for the adoption of a social-ecological systems framework emphasizing ecosystem services and resilience—benefits that are largely public goods—aimed at achieving sustainability. However, a reorienta...

Forest composition and fuel loadings govern wildfire behavior and effects, influencing the vulnerability of forest carbon (C) to emission; however, key uncertainties remain regarding post-fire forest and fuel dynamics and their consequences for C vulnerability to subsequent burns. The objectives of this study were to investigate (1) how forest structure before and after fire compares to the historic natural range of variability; (2) how immediate fire effects and environmental characteristics influence patterns of change in forest structure and biomass over time after fire; and (3) how...

The oak genus (Quercus), originating approximately 56 million years ago in the temperate Americas, has diversified across the Northern Hemisphere. Oaks are integral components of various ecosystems, including temperate deciduous forests, temperate and subtropical evergreen forests, subtropical and tropical savannahs, oak-pine forests, oak-“piñon”-juniper woodlands, cloud forests, tropical premontane and montane forests, matorral (summer rain chaparral), and Mediterranean vegetation. While many species of Quercus are exceptionally large, dominant overstory trees, others exhibit a wide range...

The first efforts to restore red spruce (Picea rubens) ecosystems in the central and southern Appalachians began nearly 100 years ago, following broad scale declines that resulted from industrial logging activities and associated wildfires. While many localized efforts have occurred over the last century, the scale of red spruce restoration has dramatically increased over the last two decades. In the mid-2000s, the Central Appalachian Spruce Restoration Initiative (CASRI) was formed to bring restoration partners together, followed by establishment of the Southern Appalachian Spruce...

The widespread loss of red spruce forests across the central and southern Appalachians during the industrial logging era (1890–1940) inspired nearly a century of land conservation and restoration. This chapter covers the evolution of the restoration movement that began with Civilian Conservation Corpstree plantings in the 1930s, built momentum with the recognition of the loss of endangered species, and has grown through partnerships and supportive policies over the following decades to result in over 2.5 million trees planted and over an estimated 3,200 ha (7,907 ac) treated to accelerate...