Treesearch
Displaying 17,241 - 17,250 of 64,647 Publications- Mature California black oak (Quercus kelloggii) trees are a keystone for many Native American cultures and support important ecological values. Black oaks depend on low-intensity, relatively frequent fires to reduce competition from conifers, yet they are also vulnerable to intense fires. Restoring mature, large canopy oaks that produce high quality acorns for tribal gatherers will depend upon reestablishing a more frequent fire regime. However, in many areas that have become overly dense, thinning treatments, out-of-season burns, and/or relatively severe fires may be needed to reopen the...AuthorsJonathan W. Long, Lenya Quinn-Davidson, Ron W. Goode, Frank K. Lake, Carl N. SkinnerKeywordsSourceGen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 113-122Year2015
- It is recognized that California Indians have stewarded the landscape for millennia. As such, the coupling of fire and culture are interrelated and interdependent in many California ecosystems including oak woodlands. Colonization and subsequent governmental fire policy mandates have disrupted the cultural use of fire, which in turn has disrupted ecological functions where those fires are absent. As society grapples with the devastating impacts of wildfires and the loss of biological diversity, many Indigenous people see traditional fire use as a key to mitigation of devastating losses...AuthorsDon L. HankinsKeywordsSourceGen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 123-129Year2015
- Although medusahead (Taeniatherum caput-medusae) is one of the most dominant invasive rangeland grasses in the West, we know surprisingly little about the environmental factors that drive medusahead abundance. Understanding the conditions that influence spread dynamics is central for developing effective monitoring, prevention and control programs. We established grassland plant communities and added medusahead seed across a range of five densities (from 0 to 50,000 seeds per m2) in open grassland and oak savannah habitat. We followed plants throughout the season to understand how habitat...AuthorsElise S. Gornish, Jeremy J. James, Emilio A. LacaSourceGen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 131-143Year2015
- This study describes a thinning and resprout control study in Madera County. The study site was a dense, 40-year old interior live oak stand (Quercus wislizeni) that originated from resprouting, with 100 percent canopy cover. Tree thinning was initiated in 1998 in cooperation with the local Resource Conservation District to evaluate thinning treatment to reduce first risk and to increase forage production. Three thinning treatments were evaluated: (1) thin one-third of the standing tree basal area (resulting in a post-thin basal area of 46 square feet per acre); (2) thin two-thirds of the...AuthorsRichard B. Standiford, Neil K. McDougaldKeywordsSourceGen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 137-143Year2015
- Sitka, Alaska, has substantial hydroelectric resources, limited driving distances, and a conservation-minded community, all suggesting strong opportunities for achieving a low community carbon footprint. In this research we evaluate the level of carbon dioxide (CO2) emissions from Sitka and compare this to the estimated CO2 sequestration potential of forest ecosystems. We determine whether a carbonneutral community is attained when these two factors are balanced. Our analysis consisted of two parts: estimating anthropogenic CO2 emissions from Sitka, and comparing this value to estimates of...AuthorsDavid L. Nicholls, Trista PattersonKeywordsSourceGen. Tech. Rep. PNW-GTR-918. Portland, OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 25 p.Year2015
- Little information is available on the metrics of coarse woody debris (CWD) in California oak woodland, most notably at the scale of the stand and woodland type. In a remote part of the National Guard Post, Camp Roberts, that has not burned in over a half century, we tallied 314 pieces of CWD in a blue oak (Quercus douglasii)-coast live oak (Q. agrifolia) woodland with patches of tree-sized bigberry manzanita (Arctostaphylos glauca). Compared to its representation in the live tree community, blue oak trees produced only half of the pieces of CWD expected. In contrast, coast live oak trees...AuthorsWilliam D. Tietje, Michael A. Hardy, Christopher C. YimKeywordsSourceGen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 61-72.Year2015
- European starlings (Sturnus vulgaris) are a remarkably successful invasive species known to compete with native bird species for nest sites. The objective of this study was to understand why starlings avoid ungrazed pastures and provide recommendations to help mitigate the impacts of starlings on native bird species. I used aviary trials to examine the effects grazing and mowing practices on starling foraging behavior. In experiment 1, I examined the effects of grass height and litter. Starlings preferred to forage in short grass without litter. In Experiment 2, I modified the treatments...AuthorsKathryn L. PurcellKeywordsSourceGen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 73-81.Year2015
- Fishers (Pekania pennanti) occur in ponderosa pine, mixed conifer, and mixed hardwood conifer habitats in the southern Sierra Nevada at elevations from approximately 1400 to 2300 m. They are a candidate species for listing under both the Federal and California Endangered Species Acts. Since 2007, the U.S. Department of Agriculture, Forest Service (USDA FS) Pacific Southwest Research Station has been investigating fisher habitat selection in the mixed hardwood conifer landscape of the Sierra National Forest. California black oaks (Quercus kelloggii) occur in the forest types fishers occupy...AuthorsCraig M. Thompson, Kathryn L. Purcell, Rebecca E. Green, Richard SweitzerKeywordsSourceGen. Tech. Rep. PSW-GTR-251. Berkeley, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station: 83-95.Year2015
- A significant amount of the forestland in Montana is in need of mechanical forest restoration treatments, which can improve forest health and reduce wildfire risk, but can be expensive to implement and produce little merchantable timber. One option for disposal of the small diameter material produced by these treatments is to utilize it to produce energy, which can offset some fossil fuel use and facilitate the treatment of more acres of forest. However the harvest and utilization of woody biomass for energy generation can have negative effects on air quality and forest health as well....AuthorsRobert Campbell, Tyron Venn, Nathaniel AndersonKeywordsSourcePaper prepared for presentation at the 2015 Agricultural and Applied Economics Association and Western Agricultural Economics Association Annual Meeting; San Francisco, CA; July 26-28. 19 p.Year2015
- High up-front costs and uncertain return on investment make it difficult for land managers to economically justify large-scale fuel treatments, which remove trees and other vegetation to improve conditions for fire control, reduce the likelihood of ignition, or reduce potential damage from wildland fire if it occurs. In the short-term, revenue from harvested forest products can offset treatment costs and broaden opportunities for treatment implementation. Increasingly, financial analysis of fuel treatments is also incorporating long-term savings through reduced fire suppression costs,...AuthorsMatthew P. Thompson, Nathaniel AndersonSourceCalifornia Agriculture. 69(3):164-170.Year2015