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Showing 1 to 20 of 94 for “"ponderosa pine"”.
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Factors that influence ponderosa pine duff mound consumption
When applying prescribed fire to long-unburned but fire-dependent ecosystems managers require better decision-support models to determine appropriate conditions for achieving desired effects. Prolonged combustion in duff accumulations at the base of large conifers can lead to fine root mortality, …
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Factors that influence ponderosa pine duff mound consumption
When applying prescribed fire to long-unburned but fire-dependent ecosystems managers require better decision-support models to determine appropriate conditions for achieving desired effects. Prolonged combustion in duff accumulations at the base of large conifers can lead to fine root mortality, …
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Modeling Endemic Bark Beetle Populations in Southwestern Ponderosa Pine Forests
… and space. Site maximum dbh and the number of ponderosa pines per acre were significant (P <.029) for predicting the probability a rise in the population density of bark beetles. Tree, stand, and beetle pressure were significant (P < .001) in predicting the probability of beetle caused tree …
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Radiolysis of the Extract from the Sawdust of the Ponderosa Pine
<p>Portions of an acetone-hexane (1:4) extract of Ponderosa pine sawdust were exposed to gamma and ultraviolet radiation. The three solutions, including the original, were checked for antibiotic activity on: Staphylococcus aureus Escherichia coli and Bacillus cereus. Results indicated that each …
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Effects of Growth Environment on Aboveground Carbon Budgets in Ponderosa Pine
In a separate study I measured ponderosa pine saplings grown in CO$\sb2$-enriched atmospheres. Trees grown under elevated CO$\sb2$ concentrations (ambient + 350 ppm) had higher temperature coefficients of respiration than trees grown under current ambient concentrations (approx. 350 ppm) and this …
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Comparing crown fire predictions in ponderosa pine stands among four fire behavior models
… representative of treated and untreated ponderosa pine forest stands in the southern Rocky Mountains. All four models predicted crown fire occurrence for 71% of simulations in total. WFDS, QUIC-Fire, and CFIS agreed on fire type more than 65% of the time. Rothermel predicted crown fire …
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Fire, climate, and forest structure in ponderosa pine forests of the Black Hills
A prevailing model for historical conditions in ponderosa pine forests is that frequent surface fires maintained open, low-density forest stands composted primarily of old, large trees. However, this model may not apply uniformly to ponderosa pine forests in the Black Hills of southwestern South …
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Embryonic control of isocitrate lyase activity in the megagametophyte of Ponderosa pine seeds
… from the embryo of stratified germinating Pinus ponderosa seeds. In contrast, the data reported here indicate the rate of increase in specific activity of embryoless seeds was greater during the first four days than in seeds with embryos left in situ. A similar pattern of activity was observed in …
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Big Game Habitat Utilization in Noncommercially Thinned Ponderosa Pine in Custer State Park
During the 1980’s , noncommercial thinning of ponderosa pine (Pinus ponderosa) was used to improve big game habitat in Custer State Park, South Dakota. Thinning densely stocked ponderosa pine created more diverse and productive foraging areas for big game species. This study evaluated utilization …
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Free living nitrogen-fixation in ponderosa pine/Douglas-fir forests in western Montana
… a significant amount of N to low elevation ponderosa pine/Douglas-fir forests in western Montana. Free-living N-fixing bacteria in soils were found to make a significant, yet modest N contribution to the forest ecosystem. Nitrogen demand by trees and shrubs are being maintained by residual …
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Free living nitrogen-fixation in ponderosa pine/Douglas-fir forests in western Montana
… a significant amount of N to low elevation ponderosa pine/Douglas-fir forests in western Montana. Free-living N-fixing bacteria in soils were found to make a significant, yet modest N contribution to the forest ecosystem. Nitrogen demand by trees and shrubs are being maintained by residual …
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Water Relations of Ponderosa Pine in Contrasting Environments: Implications for Global Climate Change
… relations of trees and forests. I used stands of ponderosa pine growing along a climate gradient (desert v. montane) in the western United States as a model system to determine the effects these climate-related shifts in biomass allocation on the water relations of mature trees. I found that …
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Causal factors and consequences of mixed-severity fire in Black Hills ponderosa pine forests
… the theme of mixed- severity fire in Black Hills ponderosa pine forests. Mixed severity fire resulted in many patches of low, moderate, and high severity, distributed in roughly equal proportion across the burned landscape. There was a significant effect of stand structure and topography on burn …
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