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You searched for +publisher:"Oregon State University" +contributor:("Salwasser, Hal"). Showing records 1 – 2 of 2 total matches.

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Oregon State University

1. Stokely, Thomas. Interactive effects of silvicultural herbicides and cervid herbivory on early seral plant communities of the northern Oregon Coast Range.

Degree: MS, Forest Ecosystems and Society, 2014, Oregon State University

Intensive forest management (IFM, dense conifer plantings and herbicide applications) may alter the characteristics of early seral plant communities that function as major habitat resources for a host of wildlife species, including cervid herbivores such as Cervus elaphus and Odocoileus hemionus. Such large herbivores can also substantially affect plant community characteristics and succession, especially in disturbed early seral habitats. I hypothesized that the effect of cervid herbivory on early seral plant communities is mediated by the effect of silvicultural herbicide treatments. If that is the case, intensively treated stands with low plant cover and diversity should be most susceptible to herbivory, as cervids are less selective and herbivory impacts are highly concentrated where forage has been diminished. To test this hypothesis, I experimentally established paired 225 m² cervid Exclusion and Open-Herbivory treatment plots in 28, 12-15 ha early seral plantation stands throughout the northern Oregon Coast Range, USA, representing a gradient in IFM. The gradient included three herbicide treatments and a no-spray Control applied at the stand scale and replicated using a randomized complete block design. I compared estimates of cover, height and diversity for entire plant communities and specific functional groups among herbivory and herbicide treatments using mixed-effects models with a blocked split-plot design. I found convincing evidence that the effect of herbivory was mediated by herbicide treatment. No-spray Control stands were too vigorous, diverse and rich with native perennial herb and deciduous shrub forage to be substantially impacted by cervid herbivory. The herbaceous specific, Light herbicide treatment reduced Shannon diversity and the cover and richness of native-perennial herbs, releasing deciduous shrub height growth where cervids where excluded. Highly selective herbivory suppressed the shrub height response by 20.5 cm, increasing the abundance and richness of introduced herb species. The broad spectrum, Moderate herbicide treatment reduced diversity, forage cover and diminished the cover and richness of deciduous shrubs and native-perennial herbs, favoring the dominance of introduced-ruderal herbs. Herbivory in the Moderate treatment reduced total cover by 17.7 percent cover, moderate-quality forage cover by 13.2 percent cover and native perennial herb richness by 1.5 species, while suppressing the cover of introduced-ruderal herbs by 4.58 percent cover and reducing the height of ferns and introduced-perennial herbs by 19.9 and 17.3 cm, respectively. Plant communities subject to the Heavy treatment were the most depauperate of all and herbivory exacerbated the effect of this treatment on native-perennial herbs only. Average height of dominant vegetation was consistently lower with cervid access across all stands, especially with Moderate herbicide treatment. My results provide evidence that by reducing diversity and the abundance of native forage species, herbicide treatments altered… Advisors/Committee Members: Betts, Matthew G. (advisor), Salwasser, Hal (committee member).

Subjects/Keywords: cervid; Herbicides  – Environmental aspects  – Oregon

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Stokely, T. (2014). Interactive effects of silvicultural herbicides and cervid herbivory on early seral plant communities of the northern Oregon Coast Range. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/50309

Chicago Manual of Style (16th Edition):

Stokely, Thomas. “Interactive effects of silvicultural herbicides and cervid herbivory on early seral plant communities of the northern Oregon Coast Range.” 2014. Masters Thesis, Oregon State University. Accessed January 18, 2020. http://hdl.handle.net/1957/50309.

MLA Handbook (7th Edition):

Stokely, Thomas. “Interactive effects of silvicultural herbicides and cervid herbivory on early seral plant communities of the northern Oregon Coast Range.” 2014. Web. 18 Jan 2020.

Vancouver:

Stokely T. Interactive effects of silvicultural herbicides and cervid herbivory on early seral plant communities of the northern Oregon Coast Range. [Internet] [Masters thesis]. Oregon State University; 2014. [cited 2020 Jan 18]. Available from: http://hdl.handle.net/1957/50309.

Council of Science Editors:

Stokely T. Interactive effects of silvicultural herbicides and cervid herbivory on early seral plant communities of the northern Oregon Coast Range. [Masters Thesis]. Oregon State University; 2014. Available from: http://hdl.handle.net/1957/50309


Oregon State University

2. Tuitele-Lewis, Jeannette D. Agroforestry farming in American Samoa : a classification and assessment.

Degree: MS, Forest Science, 2004, Oregon State University

Agroforestry is a traditional farming practice in American Samoa that has helped to sustain the livelihood of the native population for centuries. These once self-sufficient islands have become economically dependent on U.S monies and other external resources during the past century. Dependency has caused a shift in the carrying capacity of the islands and has changed cultural attitudes regarding land use. This attitude is expressed on the landscape of changing agricultural and communal lands. Preserving traditional agroforestry practices and improving these systems may be important factors contributing to the future ecological, economic, and cultural sustainability of the territory. The goal of this study was to document and describe agroforestry farming in American Samoa in order to provide base-line information regarding the utilization of agroforestry species, agroforestry farming incentives and constraints, and current practices and systems. Thirty-eight farmers were randomly selected and farmer interviews and field surveys were conducted between the months of May-August 2003. Formal survey questions for the interview were divided into five major sections: woody species usage, livestock, inputs and soil, land tenure, and farmer demographics. Site selection corresponded with the participant farmers. Basic topographical information was collected for each site. Agroforestry practices mentioned during the interview process that were observed on site were documented. Each agroforestry site was placed into an initial classification type based on a visual assessment of plot size, species diversity, and vertical vegetative structure. Subplot data regarding species composition and vertical canopy structure was measured for each site. Data collection was divided into five vertical layers primarily by height: 1) low crop (<1.5m), 2) shrub/sapling (1.5-4m), 3) small tree (4-l0m), 4) large tree (10+m) and 5) climbing vines. For each subplot all ethnobotanically useful plant species were identified. Percent cover of useful species in each stratum layer was estimated and assigned one of seven percent cover classes. Subplot cover classes were averaged to obtain a single site estimate for each species in each stratum. Results from the farmer interviews suggest that agroforestry systems continue to be an important cultural and product resource in American Samoa. Although there is no longer the same level of dependency on these systems for meeting basic needs, agroforestry products continue to supplement household diets and are utilized for a variety of non-timber forest products and ecological services. Several agroforestry practices were observed among the farms in the study. However, the effectiveness of some of the practices including windbreaks, fallow, and erosion control was not optimal. This indicated that farmers could greatly benefit from institutionalized agroforestry practices such as appropriate spacing for wind filtration, improved fallow, and contour farming. Incentives and constraints for practicing… Advisors/Committee Members: Radosevich, Steven R. (advisor), Salwasser, Hal (committee member).

Subjects/Keywords: Agroforestry  – American Samoa

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Tuitele-Lewis, J. D. (2004). Agroforestry farming in American Samoa : a classification and assessment. (Masters Thesis). Oregon State University. Retrieved from http://hdl.handle.net/1957/11055

Chicago Manual of Style (16th Edition):

Tuitele-Lewis, Jeannette D. “Agroforestry farming in American Samoa : a classification and assessment.” 2004. Masters Thesis, Oregon State University. Accessed January 18, 2020. http://hdl.handle.net/1957/11055.

MLA Handbook (7th Edition):

Tuitele-Lewis, Jeannette D. “Agroforestry farming in American Samoa : a classification and assessment.” 2004. Web. 18 Jan 2020.

Vancouver:

Tuitele-Lewis JD. Agroforestry farming in American Samoa : a classification and assessment. [Internet] [Masters thesis]. Oregon State University; 2004. [cited 2020 Jan 18]. Available from: http://hdl.handle.net/1957/11055.

Council of Science Editors:

Tuitele-Lewis JD. Agroforestry farming in American Samoa : a classification and assessment. [Masters Thesis]. Oregon State University; 2004. Available from: http://hdl.handle.net/1957/11055

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