Treesearch

Recently, a collaboration between The Brenton Arboretum and the North Central Regional Plant Introduction Station (NCRPIS) was initiated to assemble comprehensive ex situ germplasm collections of Kentucky coffeetree, Gymnocladus dioicus. Gymnocladus dioicus was selected due to its adaptation to poor soils common to urban conditions, extreme drought tolerance, and no reported serious insect or disease problems. These factors make it a promising candidate among diverse tree genera to replace ash trees in urban environments affected by the emerald ash borer (Agrilus planipennis). Targeted...

Restoration treatments in the ponderosa pine (Pinus ponderosa P. & C. Lawson) ecosystems of the southwestern United States often include removing over 80 percent of post-EuroAmerican settlement-aged trees to create healthier forest structural conditions. These types of stand density reductions can have negative effects on genetic diversity. Allozyme analyses were used to evaluate potential impacts of restoration treatments on genetic diversity of five ponderosa pine populations located 2 to 3 km apart within the U.S. Department of Agriculture Forest Service Fort Valley Experimental Forest,...

Because of rapid global warming, it is critical for us to better understand the capacity of forest trees to adapt to a changing climate, especially species such as five-needle pines that are particularly at risk to threats because of fire suppression, population fragmentation, and pests. In this study, we used several methods to disentangle the effects of local adaptation (isolation by environment, IBE) from those of isolation by distance (IBD) and isolation by colonization (IBC) in Pinus strobus. For this reason, 153 SNPs from 103 genes, including 44 candidate genes for growth and...

Ex-situ genetic conservation focused on collection and storage of seed can play an important role in conserving the genetic diversity of species under grave threat by biotic organisms or a changing climate. However, ex-situ genetic conservation is primarily a static activity and does not allow for evolution of the species under a continuing, persistent impacting agent. Invasive insects and pathogens, once established, usually become permanent components of the ecosystem, continuously interacting with the target species. Dynamic genetic conservation seeks to actively harness the genetic...

North American native tree species in forest ecosystems, as well as managed forests and urban plantings, are being severely impacted by pathogens and insects. The impacts of these pathogens and insects often increase over time, and they are particularly acute for those species affected by non-native pathogens and insects. For restoration of affected tree species or for their continued presence in managed forests and urban plantings, genetic resistance will be key. Often, however, little or nothing is known about genetic resistance to these invaders. The U.S. Department of Agriculture...

A strong focus on tree germplasm that can resist threats such as non-native insects and pathogens, or a changing climate, is fundamental for successful genetic conservation efforts. However, the unavailability of tools for rapid screening of tree germplasm for resistance to critical pathogens and insect pests is becoming an increasingly serious bottleneck. Here we present the development of a new technique that can potentially revolutionize genetic conservation efforts. Fourier-transform infrared (FT-IR) spectroscopy is a chemical fingerprinting technique that has been recently shown to be...

The American Chestnut Foundation (TACF) has worked since 1983 to introduce genetic resistance to the chestnut blight fungus (Cryphonectria parasitica) into an American chestnut (Castanea dentata) population. As part of a broader goal for species restoration, TACF seeks to instill within that population sufficient diversity so as to enable the species to reproduce on its own in forests throughout its native range. Dr. Charles Burnham proposed introgressing blight-resistance from Asian chestnut species into a predominantly American chestnut genetic background with backcross breeding. Hybrids...

How do we conserve tree diversity in a rapidly changing world, dominated by intensive human impact on the landscape? The Anthropocene is a useful term to describe a new era in Earth’s history, where we dominate the globe’s resources so completely that our activities alter basic nutrient, water, climate, and energy cycles. These rapid environmental changes and the substantial decline in available and appropriate habitat for many organisms has led to predictions of a sixth global extinction event, where a large fraction of the world’s species are lost. These mass extinctions clearly impacted...

Forests are thought to adapt too slowly to anthropogenic climate change, making them highly vulnerable to large-scale loss. Losses can accrue swiftly because generations are lengthy, particularly at higher latitudes (>23⁰ to 73⁰) where wind-pollinated forest species are commonly found to mature slowly. Losses incurred during adaptation to climate change translates into less allelic richness, or genetic diversity, and one can expect some resilience on this point because forests have more genetic diversity than other seed plants and this feature has shaped the forest fragmentation paradox...

American Public Gardens Association, founded in 1940, represents over 600 member gardens spanning North America and 24 countries. Its diverse membership includes botanic gardens, arboreta, and other public gardens which contribute to tree gene conservation. Some maintain ex situ collections nationally accredited through the Association’s Plant Collections Network, a 21-year collaboration with the U.S. Department of Agriculture (USDA) Agricultural Research Service. This program promotes excellence in curatorial practices while facilitating a continent-wide approach to germplasm preservation....