Treesearch
Displaying 17,901 - 17,910 of 65,182 Publications- The elastic properties of pit membranes are reported to have important implications in understanding air-seeding phenomena in gymnosperms, and pit aspiration plays a large role in wood technological applications such as wood drying and preservative treatment. Here we present force–displacement measurements for pit membranes of circular bordered pits, collected on a mesomechanical testing system. The system consists of a quartz microprobe attached to a microforce sensor that is positioned and advanced with a micromanipulator mounted on an inverted microscope. Membrane displacement is...AuthorsSamuel L. Zelinka, Keith Bourne, John C. Hermanson, Samuel V. Glass, Adriana Costa, Alex C. WiedenhoeftKeywordsSourcePlant, Cell & EnvironmentYear2015
- Two isolates of Chlorociboria aeruginascens (Nyl.) Kanouse incubated axenically on aspen wood blocks resulted in 18% and 32% mass loss after 134 wks (2 yrs 8 mo). Aspen wood decayed by C. aeruginascens contained cavities in the S2 layer of the secondary cell wall, similar to Type I soft rot attack, as well as erosion troughs and overall thinning and erosion of wood cell walls, resembling decay by Type II soft rot fungi. Using a selective medium, basidiomycete fungi were isolated from 9 of 17 samples of wood from a variety of tree species colonized and stained by Chlorociboria sp. (putativel...AuthorsDana L. Richter, Jessie A. GlaeserKeywordsSourceInternational Biodeterioration & BiodegradationYear2015
- Large snags and logs provide important biological legacies and resources for native wildlife, yet data on populations of large snags and logs and factors influencing those populations are sparse. We monitored populations of large snags and logs in mixed-conifer and ponderosa pine (Pinus ponderosa) forests in northern Arizona from 1997 through 2012. We modeled density of large snags and logs as a function of forest type, time period, and environmental characteristics of sampled plots. Our objective was to build models that best explained current densities of these structures using these...AuthorsJoseph L. Ganey, Benjamin J. Bird, Scott Baggett, Jeffrey S. JennessKeywordsSourceForest Science. 61(2): 353-362.Year2015
- Snags (standing dead trees) are important components of forests that provide resources for numerous species of wildlife and contribute to decay dynamics and other ecological processes. Managers charged with managing populations of snags need information about standing rates of snags and factors influencing those rates, yet such data are limited for ponderosa pine (Pinus ponderosa) and especially mixed-conifer forests in the southwestern United States. We monitored standing rates of snags in 1-ha plots in Arizona mixed-conifer (n = 53 plots) and ponderosa pine (n = 60 plots) forests from...AuthorsJoseph L. Ganey, Gary C. White, Jeffrey S. Jenness, Scott VojtaKeywordsSourceThe Journal of Wildlife Management. 79(8): 1369-1377.Year2015
- Fruits produce a wide range of volatile organic compounds that impart their characteristically distinct aromas and contribute to unique flavor characteristics. Fruit aroma and flavor characteristics are of key importance in determining consumer acceptance in commercial fruit markets based on individual preference. Fruit producers, suppliers and retailers traditionally utilize and rely on human testers or panels to evaluate fruit quality and aroma characters for assessing fruit salability in fresh markets. We explore the current and potential utilization of electronic-nose devices (with...AuthorsManuela Baietto, Dan D. WilsonSourceSensors 15:899-931Year2015
- Conservation of species requires accurate population estimates. We used genetic markers from feces to determine bighorn sheep abundance for a herd that was hypothesized to be declining and in need of population status monitoring. We sampled from a small but accessible portion of the population’s range where animals naturally congregate at a natural mineral lick to test whether we could accurately estimate population size by sampling from an area where animals concentrate. We used mark-recapture analysis to derive population estimates, and compared estimates from this smaller spatial...AuthorsKathryn A. Schoenecker, Mary Kay Watry, Laura E. Ellison, Michael K. Schwartz, Gordon L. LuikartKeywordsSourceWestern North American Naturalist. 75(2): 181-191.Year2015
- The global loss of biodiversity continues at an alarming rate. Genomic approaches have been suggested as a promising tool for conservation practice as scaling up to genome-wide data can improve traditional conservation genetic inferences and provide qualitatively novel insights. However, the generation of genomic data and subsequent analyses and interpretations remain challenging and largely confined to academic research in ecology and evolution. This generates a gap between basic research and applicable solutions for conservation managers faced with multifaceted problems. Before the...AuthorsAaron B. A. Shafer, Jochen B. W. Wolf, Paulo C. Alves, Linnea Bergstrom, Michael W. Bruford, Ioana Brannstrom, Guy Colling, Love Dalen, Luc De Meester, Robert Ekblom, Katie D. Fawcett, Simone Fior, Mehrdad Hajibabaei, Jason A. Hill, A. Rus Hoezel, Jacob Hoglund, Evelyn L. Jensen, Johannes Krause, Torsten N. Kristensen, Michael Krutzen, John K. McKay, Anita J. Norman, Rob Ogden, E. Martin Osterling, N. Joop Ouborg, John Piccolo, Danijela Popovic, Craig R. Primmer, Floyd A. Reed, Marie Roumet, Jordi Salmona, Tamara Schenekar, Michael K. Schwartz, Gernot Segelbacher, Helen Senn, Jens Thaulow, Mia Valtonen, Andrew Veale, Philippine Vergeer, Nagarjun Vijay, Carles Vila, Matthias Weissensteiner, Lovisa Wennerstrom, Christopher W. Wheat, Piotr ZielinskiKeywordsSourceTrends and Ecology in Evolution. 30(2): 78-87.Year2015
- Biomass ash is an important and potentially useful by-product of the bioenergy industry. As a "proof of concept" for using biomass fly ash as a foliar fertilizer, we tested (i) whether the nutrients in the ash were absorbed by hybrid aspen trees, (ii) whether the ash affected tree growth, and (iii) whether the ash was compatible with nitrogen foliar fertilizer. Four foliar treatments (water [control], ash suspended in water, nitrogen fertilizer solution, and ash suspended in nitrogen fertilizer solution) were evaluated. Several nutrients in the fly ash were absorbed by hybrid aspen both in...AuthorsWilliam Headlee, Richard HallKeywordsSourceJournal of Plant Nutrition. 38: 647-662.Year2015
- The Forest Service Tree Climbing Program provides direction that protects Forest Service employees while ascending, descending, and working aloft in trees by establishing national direction based on recognized industry standards, procedures and practices. Climbing and working in trees demands specialized equipment and skills. The potential for a serious injury or fatal fall is always present, so employees shall be trained and certified before they engage in tree climbing operations and activities. The Forest Service Silvicultural Practices Handbook, FSH 2409.17, Chapter 50-Forest Tree...AuthorsJerry Berdeen, Burnham Chamberlain, Teryl G. Grubb, Art Henderson, Brock Mayo, Manfred Mielke, Kathryn L. Purcell, Dennis Ringnes, Marc Roberts, Donna Stubbs, Micah ThorningSourceTech. Rep. 0567-2819-MTDC. Missoula, MT: U.S. Department of Agriculture, Forest Service, Missoula Technology and Development Center. 88 p.Year2015
- Nearest neighbors techniques calculate predictions as linear combinations of observations for a selected number of population units in a sample that aremost similar, or nearest, in a space of auxiliary variables to the population unit requiring the prediction. Nearest neighbors techniques have been shown to be particularly effective when used with forest inventory and remotely sensed data. Recent attention has focused on developing an underlying foundation consisting of diagnostic tools, inferential extensions, and techniques for optimization. For a study area in Norway, forest inventory...AuthorsRonald E. McRoberts, Erik Næsset, Terje GobakkenKeywordsSourceRemote Sensing of EnvironmentYear2015