Treesearch

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....

The southern United States is home to some of the world’s most biologically diverse temperate forests. These forests range from the Atlantic and Gulf coastal plains to the Southern Appalachian Mountains and are home to more than 140 tree species which provide a number of ecosystem services, including clean air and water, carbon storage, recreational opportunities, wood, and fiber to feed a growing population’s need for solid wood and paper products. Many of these species are threatened by natural and human-caused disturbances, including native and exotic insects, diseases, invasive plants,...

Among forest-associated plant species in the United States, less than one percent has been determined to be extinct. However, 57 trees or trees/shrubs are officially listed as threatened or endangered by the U.S. Department of Interior Fish and Wildlife Service. Most of these listed species are tropical island endemics; 35 are from Hawaii and 13 from Puerto Rico and/or the United States Virgin Islands. As required by law, these listed species have restoration plans that are in some state of implementation. Federal land management agencies also strive to conserve species that are considered...

Predicting how forest carbon cycling will change in response to climate change and management depends on the collective knowledge from measurements across environmental gradients, ecosystem manipulations of global change factors, and mathematical models. Formally integrating these sources of knowledge through data assimilation, or model–data fusion, allows the use of past observations to constrain model parameters and estimate prediction uncertainty. Data assimilation (DA) focused on the regional scale has the opportunity to integrate data from both environmental gradients and experimental...

Camcore is an international tree breeding and conservation program with headquarters at North Carolina State University. Camcore was founded in 1980 as a cooperative, non-profit organization to identify and save the dwindling natural populations of pines in the highland regions of Guatemala in Central America. Funded by the private sector, the program has played an important role as an international gene conservation cooperative. The program emphasizes ex situ conservation as a complement to in situ conservation to ensure that a wide range of genetic variation in a species is protected....

A comparative study was done on Liquidambar Orientalis Mill heartwood extractive samples. These extractives were collected from wood decay specimens. The objective of the study was to determine the chemical composition of the extractives remaining after exposure to brown rot fungi Tyromyces Palustris and white rot fungi Trametes Vericolor. All samples were extracted according to TAPPI Standard T-204. Samples were put through two different solvent systems and characterized by analytical techniques for any changes in chemical and morphological properties. The extracted chemicals collected...

Over the last 200 years, humans have impacted the genetic diversity of forest trees. Because of widespread deforestation and over-exploitation, about 9,000 tree species are listed worldwide as threatened with extinction, including more than half of the ~600 known conifer taxa. A comprehensive review of the floristic-taxonomic literature compiled a list of 4,331 recorded tree species in Mexico. The highest diversity of pine and oak worldwide is located in the Mexican temperate forests. Because species diversity and genetic diversity are often positively associated, there is expectation of...

The goal of our research and development efforts is to restore American elm (Ulmus americana) as a species in both natural and urban landscapes. Accomplishing this goal requires identification/generation of additional American elm cultivars that are tolerant to Dutch elm disease (DED) caused by Ophiostoma ulmi and O. novo-ulmi, and development of methods to reintroduce American elm along the rural to urban gradient. To accomplish our goal we are screening large survivor trees for DED tolerance, generating DED-tolerant/site-adapted cultivars, generating three regional seed orchards,...

Laurel wilt disease is incited by the exotic fungus Raffaelea lauricola and transmitted by the Asian redbay ambrosia beetle (Xyleborus glabratus). The disease has spread from Savannah, Georgia in 2002 across the coastal southeast as far south as the Everglades, and in 2014 was discovered as far west as Texas. Mortality is severe, with locations in Florida reporting more than 90 percent loss of redbays, 7.6 to 10.2 cm (3 to 4 inches) in diameter and greater. Surviving redbays from coastal maritime forest ecosystems have been collected and propagated for the study of disease resistance and...

Climate change presents new challenges to land managers. At stake is our ability to make thoughtful, science-based decisions and to add climate change considerations to our project and management plans. We also must prioritize among the opportunities that can be included in adaptation strategies because funding and time are limited, now more than ever. In 2012, we conducted a vulnerability assessment of common overstory forest tree species for the Pacific Northwest and provided recommended actions based on the results of this assessment. These recommendations will sharpen the focus of...