Treesearch

To properly parameterize physics-based models of wildland fire behavior, it is necessary to understand the magnitude of convective heat transfer in various scenarios. In order to do so, we isolated the con- vective heating process in an idealized wildland fuel: pine needle litter layers. A heated wind tunnel was used to obtain a Reynolds number dependent correlation for the Nusselt number for: (1) a sin- gle representative fuel element, and (2) the bulk porous medium - both exposed to sudden pulses of high temperature air. The former was obtained through resistive thermometry and the...

Efforts to develop American chestnuts [Castanea dentata, (Marsh.) Borkh], with improved resistance to the chestnut blight fungus, Cryphonectria parasitica (Murr.) Barr, and Phytophthora root rot, caused by Phythophthora cinnamomi Rands, are ongoing. Establishing founder populations of improved chestnut will require understanding the ecological and silvicultural requirements of the species. In areas where white tailed deer (Odocoileus virginianus Zimmerman) hinder tree regeneration success, understanding how browsing will affect the establishment of planted chestnut is critical. We evaluated...

Urbanization is one of the most widespread and extreme examples of habitat alteration. As humans dominate landscapes, they introduce novel elements into environments, including artificial light, noise pollution, and anthropogenic food sources. One understudied form of anthropogenic food is refuse from restaurants, which can alter wildlife populations and, in turn, entire wildlife communities by providing a novel and stable food source. Using data from the Maricopa Association of Governments and the Central Arizona-Phoenix Long Term Ecological Research (CAP LTER) project, we investigated...

There is increasing momentum to implement conservation and management approaches that adapt forests to climate change so as to sustain ecosystem functions. These range from actions designed to increase the resistance of current composition and structure to negative impacts to those designed to transition forests to substantially different characteristics. A component of many adaptation approaches will likely include assisted migration of future climate-adapted tree species or genotypes. While forest-assisted migration (FAM) has been discussed conceptually and examined experimentally for...

Uncertainty and emerging threats associated with climate change necessitate the development of new approaches for managing forest ecosystems. To address this need the Adaptive Silviculture for Climate Change (ASCC) Network was established to examine the efficacy of three climate adaptation strategies in important forest types across North America: 1) resistance to change by increasing overstory tree health through reduced inter-tree competition, 2) resilience by creating conditions that allow change within the natural range of variability while encouraging greater abundance of native...

Black ash (Fraxinus nigra Marsh.) forests of north-central North America are currently threatened by the non-native emerald ash borer (Agrilus planipennis, EAB). Despite the wide distribution of F. nigra ecosystems, and the concern over EAB impact, little is known about their structure and natural stand dynamics. We sampled six old-growth F. nigra stands to assess structure, composition, tree recruitment, and past disturbance. Dendrochronological results revealed that disturbance rates fluctuated markedly over the past 200 years or more, but remained relatively low, suggesting small- to...

Combined heat and moisture transfer modeling is used in building envelope analysis to identify potential moisture durability risks. Moisture transfer in porous materials is typically partitioned into liquid transport and vapor diffusion. Although modeling approaches differ in complexity, coefficients for liquid transport are often derived from laboratory measurements of water absorption by partial immersion. Models generally include the assumption that capillary transport is dominant during the measurement, while vapor diffusion is negligible. This is reasonable for mineral-based materials,...

As a private forest landowner, you may start to think about timber taxes only after having a timber sale. However, each forest activity you conduct can have tax implications. Generally, all income received is taxable unless excluded by tax law, and nothing is deductible unless a provision allows it. Understanding the forest-related provisions and integrating tax planning into your forest management can help lower your overall taxes and increase disposable income. This publication is intended to be an informational and educational resource for you and your tax advisor, but is not intended...

We consider how the stoichiometry and energy content of organic matter reservoirs and fluxes through and from a peatland enable the fluxes and storage of carbon within a peatland to be constrained. We include the elemental composition of the above- and below-ground biomass, litter, the peat profile, and the dissolved and particulate organic matter within a blanket bog in northern England for which the C budget has previously been measured. The study shows, based only on the elemental composition, and calculation of oxidation and energy contents, that: (a) Dissolved organic carbon (DOC) in...

This report provides a look at changes that could come to pass and impact recreation on public lands over the next 30 years. The data were over 700 horizon scan hits from our Forest Futures Horizon Scanning Project. Horizon scan hits are a useful early warning system. Horizon scan hits may be directly related to outdoor recreation (e.g., the decline of snow fall) or they may be indirectly related (e.g., the development of lab-grown meat). Because weak signals of change are as important as strong signals, a single scan hit is worthy of consideration, even if it stands alone. These horizon...