We evaluated the regeneration behavior and early growth rates of 10 non-pioneer canopy tree species in medium-height, semi-evergreen dry tropical forest in Quintana Roo, Mexico. These species provide timber and non-timber forest products for local communities and include evergreen and deciduous species with varied dispersal mechanisms. The species were Coccoloba...
Recent studies suggest that competition from brook trout (Salvelinus fontinalis; EBT) may have negative effects (e.g. displacement) on Lahontan cutthroat trout (Oncorhynchus clarki henshawi; LCT). Results from these studies have failed to elucidate the responsible mechanisms and have not examined if changing environmental conditions result in competitive/subordinate role reversals. The...
Weeping alkaligrass (Puccinellia distans) and Nuttall’s alkaligrass (Puccinellia
nuttalliana) infest Kentucky bluegrass seed fields of eastern Oregon. Weeping
alkaligrass is an introduced species from Eurasia, whereas Nuttall’s alkaligrass is
native to semi arid environments of western North America. These species are often
referred to collectively as ‘alkaligrass’; however, for farmers...
Throughout society, many believe women are not succeeding professionally because of the institutional barriers created by men in the American workforce. However, women may be more competitive with other women than with men, especially when limited job positions are the goal. Competitiveness among women can be explained by a phenomenon...
Published September 1991. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalog
Oregon's only remaining non-reservoir population of adfluvial bull trout (Salvelinus confluentus) is found in Odell Lake, in the headwaters of the Deschutes River. The population size is unknown, but appears to be quite small. Limited spawning and rearing habitats, combined with the effects of introduced species and other anthropogenic changes...
Two major objectives were accomplished.
1. A summary of the work done during 1970-71 on a single species intra-specific competition model was written. 2. A multispecies predator-prey model, incorporating the competition mechanism of the single-species model, was developed almost to completion. The single species model is a computer program that...
At three sites in southwest Oregon, uniform stands of whiteleaf manzanita were created for future studies on the effects of manzanita competition on Douglas-fir and ponderosa pine plantations. The sites were marked according to grids and nearby 2-year-old seedlings were lifted and transplanted to fill in gaps in the natural...
This study examines the long-term role of interference on stand development of Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and red alder (Alnus rubra Bong.) planted mixtures in the Central Cascades of Oregon, USA. The two species are common associates in naturally regenerated and planted conifer stands in the Pacific Northwest. Due...