Treesearch

Fruits of Miconia calvescens DC. (Melastomataceae) were dissected to study insect frugivory in this plant in its native habitat in Costa Rica. Larvae of an unknown Mompha species (Lepidoptera: Momphidae), Anthonomus monostigma Champion (Coleoptera: Curculionidae), and unidentified Diptera and Hymenoptera were found in M. calvescens fruits. The Mompha species, described here as new as Mompha luteofascia Koster & Badenes-Pérez, was the most abundant insect frugivore in M. calvescens, infesting up to 38.1% of the fruits sampled. Feeding damage by M. luteofascia was positively correlated with...

Mule deer (Odocoileus hemionus) are widely hunted throughout western North America and are experiencing population declines across much of their range. Consequently, understanding the direct and indirect effects of hunting is important for management of mule deer populations. Managers can influence deer mortality rates through changes in hunting season length or authorized tag numbers. Little is known, however, about how hunting can affect site fidelity patterns and subsequent habitat use and movement patterns of mule deer. Understanding these patterns is especially important for adult...

This research article summarizes results from Part 1 of a study designed to examine using advanced signal processing techniques with acoustic-based lumber assessment technologies to evaluate the MOE, ultimate tension stress (UTS), and MOR of structural lumber. In Part 1 of this research article, a mathematical model of acoustic wave behavior in an idealized specimen is derived using fundamental mechanics. Published information on the physical and mechanical properties of clear, defect-free wood is input into the model to examine acoustic wave behavior. Wave behavior is then examined...

Sodium periodate has been shown to cleave glucose by specific oxidation to yield a number of non-volatile aldehydes which can react with the phenolic compounds in tannin extract and lead to tannin cross-linking and hardening. This approach to prepare a tannin resin useable for wood adhesives can be used by either treating with periodate a mixture of tannin and glucose, or to treat glucose beforehand with periodate to cleave it and generate the aldehydes, and only afterwards to mix it with the tannin. The results obtained with these two methods are identical, but the latter method avoids...

The length of the wildfire season has become longer in many regions around the world under climate change. This study investigated changes in fire season pattern (i.e., the number of separate periods of a year when wildfires are most likely to ignite, spread, and affect resources) and the contributions of climate change in Daxing'anling, Northeast China. An expanded fire dataset in both spatial and temporal converge from ground reporting was used. A comparison with satellite detected burned areas showed good agreement in spring, summer, and entire fire season. The results showed that the...

Pyrolysis of wood is a series of chemical and physical changes that occur simultaneously. Previous investigations of pyrolysis have often simplified the process. For wood building materials, the pyrolysis process is typically simplified to the formation of “char” at 300°C. Pyrolysis models are often simplified by using the thermal degradation of isolates reference polymers in an inert atmosphere. This approach assumes that the structure of bulk wood performs similarly to that of the isolated polymers being used and ignores reactions with oxygen. This dissertation explores the molecular-scal...

Wood deterioration, due to decay fungi, shortens the useful life span of wood and wood-based materials. Prescriptive preservative treatment is the most effective way to reduce the detrimental effects of these persistent microorganisms, particularly in soil contact and areas of critical use. A thorough understanding of decay hazard in soil contact is critical for proper selection and use of wood in ground contact. Current AWPA guidelines in the Use Category System specify 5 zones of severity regarding wood decay fungal hazard but contain very little information on diversity and abundance of...

This study was performed to acquire key market and raw material usage information for the wood pallet and container industry in 2016. Historical trends in the wood pallet market were also analyzed between 1991 and 2016 using the results of previous Virginia Tech pallet surveys sponsored by NWPCA and U.S. Forest Service. The wooden pallet and container industry produced an estimated 513 million new wood pallets in 2016, which is a 23% increase since 2011. Approximately 35% of this was 48" x 40" pallets, which continues to be the dominant standardized pallet size. Approximately 39% of new...

Disturbance refugia – locations that experience less severe or frequent disturbances than the surrounding landscape – provide a framework to highlight not only where and why these biological legacies persist as adjacent areas change but also the value of those legacies in sustaining biodiversity. Recent studies of disturbance refugia in forest ecosystems have focused primarily on fire, with a growing recognition of important applications to land management. Given the wide range of disturbance processes in forests, developing a broader understanding of disturbance refugia is important for...