scholarly journals Processing Value of Small-Diameter Sawtimber at Conventional Stud Sawmills and Modern High-Speed, Small-Log Sawmills in the Western United States—A Comparison

2000 ◽  
Vol 15 (4) ◽  
pp. 208-212 ◽  
Author(s):  
Francis G. Wagner ◽  
Carl E. Fiedler ◽  
Charles E. Keegan
Keyword(s):  
United States ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
High Speed ◽  
Fire Suppression ◽  
Small Diameter ◽  
Selective Logging ◽  
Western United States ◽  
Forest Composition ◽  
Delivery Costs

Abstract Past selective logging of early successional species [e.g., ponderosa pine (Pinus ponderosa)] and effective fire suppression have dramatically altered forest composition and health over millions of acres in the western United States. Implementation of ecological restoration treatments to address these conditions will produce large volumes of small-diameter sawtimber for processing. Since sawmills currently process a majority of sawtimber harvested in the West (more than 80% in some regions), this study concentrated on determining the value of small-diameter sawtimber delivered to sawmills. A conventional stud sawmill and a modern, high-speed, small-log sawmill were profiled. A simulator (MSUSP) was employed to describe these sawmills and to determine breakeven delivered-sawtimber values by dbh class for each sawmill. Data inputs included machinery type, mill layout, machine speeds, volume and grade recovery, product prices, and fixed and variable manufacturing costs. Results showed that sawtimber 9 in. dbh and under could not cover harvest and delivery costs and earn even a modest (10%) return on invested (ROI) capital at the conventional stud sawmill and that sawtimber 7.5 in. dbh and smaller had negative values. However with a 10% ROI capital, the value of all sizes of sawtimber at the modern, high-speed sawmill equaled or exceeded harvest and delivery costs. West. J. Appl. For. 15(4):208–212.

scholarly journals Stand-Level Height-Diameter Equations for Young Ponderosa Pine Plantations in Neuquén, Patagonia, Argentina: Evaluating Applications of Equations Developed in the Western United States

2004 ◽  
Vol 19 (3) ◽  
pp. 202-210
Author(s):  
Héctor E. Gonda ◽  
Douglas A. Maguire ◽  
Gustavo O. Cortés ◽  
Steven D. Tesch
Keyword(s):  
United States ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Nonlinear Models ◽  
Geographic Range ◽  
The Other ◽  
Linear Functions ◽  
Western United States ◽  
Northern Patagonia ◽  
Level Height

Abstract Two linear and two nonlinear height-diameter models commonly used in the western United States were tested for the young ponderosa pine (Pinus ponderosa) plantations of northern Patagonia, where it is the most widely planted species. The equations were fitted to each of 127 plots, located throughout the geographic range of the plantations in Neuquén province. The four equations were compared using Furnival's (1961) index of fit. Even though there were no important differences among models tested, the nonlinear model previously applied by Wykoff et al. (1982), H = 1.3 + exp(β0 + (β1/(D + 2.54))) + β was preferable because it converged more efficiently than the other nonlinear equation and was more flexible than the linear functions. Differences in the behavior of plot-level and regionwide equations demonstrated the biases possible if regionwide equations are applied to estimate missing heights within a plot. The coefficients for the two nonlinear models fitted to trees growing in several regions in the western United States generally overestimated the height of Neuquén trees. West. J. Appl. For. 19(3):202–210.

scholarly journals Historical forest changes in the western United States

2020 ◽  
Vol 96 (01) ◽  
pp. 36-49
Author(s):  
Craig Loehle
Keyword(s):  
United States ◽  
Populus Tremuloides ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Fire Regimes ◽  
Forest Growth ◽  
Western United States ◽  
Past Century ◽  
Growth Trends ◽  
The Past

Changes in factors such as temperature, precipitation, fire regimes, ozone, atmospheric CO2, and nitrogen deposition may have altered forest growth over the past century. Determining changes in forest growth over long intervals is complicated by constantly changing growing conditions due to tree maturation, stand self-thinning, disturbance, and other factors. Because a comprehensive review is lacking, results from publications examining forest growth trends in the western United States over the past 100 years were evaluated. Across the region, upper elevational forest ecotones have been expanding upward in many but not all locations, possibly due to warming and reduced snowpack. Across most of the region, both growth increases and decreases are localized and spatially dispersed. For the inland West, historical photography and long-term inventory data show clear densification and expansion of ponderosa pine (Pinus ponderosa) and mixed conifer forest across the region, mostly due to reduced fire incidence. However, a recent drought, probably linked to ocean cycles and exacerbated by warming, has caused a growth setback and mortality, especially in the Southwest. Forest densification due to altered fire regimes does not equate to enhanced growth per se. Aspen (Populus tremuloides) dieback has been noted due to recent drought and local conifer mortality caused by drought has also been documented in several locations. Regeneration after recent fires appears to be inadequate in many localities. Except for local increased growth at some high elevation and coastal sites and possible periodic drought effects in the Southwest, it is difficult to detect any growth trends with available data.

scholarly journals Over half of western United States' most abundant tree species in decline

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Hunter Stanke ◽  
Andrew O. Finley ◽  
Grant M. Domke ◽  
Aaron S. Weed ◽  
David W. MacFarlane
Keyword(s):  
United States ◽  
Tree Species ◽  
Tree Mortality ◽  
Temperate Forests ◽  
Size Structure ◽  
Forest Disturbance ◽  
Population Decline ◽  
Western United States ◽  
Scale Transformation ◽  
Forest Composition

AbstractChanging forest disturbance regimes and climate are driving accelerated tree mortality across temperate forests. However, it remains unknown if elevated mortality has induced decline of tree populations and the ecological, economic, and social benefits they provide. Here, we develop a standardized forest demographic index and use it to quantify trends in tree population dynamics over the last two decades in the western United States. The rate and pattern of change we observe across species and tree size-distributions is alarming and often undesirable. We observe significant population decline in a majority of species examined, show decline was particularly severe, albeit size-dependent, among subalpine tree species, and provide evidence of widespread shifts in the size-structure of montane forests. Our findings offer a stark warning of changing forest composition and structure across the western US, and suggest that sustained anthropogenic and natural stress will likely result in broad-scale transformation of temperate forests globally.

What drives ponderosa pine regeneration following wildfire in the western United States?

2019 ◽  
Vol 454 ◽  
pp. 117663 ◽  
Author(s):  
Julie E. Korb ◽  
Paula J. Fornwalt ◽  
Camille S. Stevens-Rumann
Keyword(s):  
United States ◽  
Ponderosa Pine ◽  
Western United States ◽  
Pine Regeneration

scholarly journals Antelope Bitterbrush and Scouler's Willow Response to a Shelterwood Harvest and Prescribed Burn in Western Montana

1999 ◽  
Vol 14 (3) ◽  
pp. 137-143 ◽  
Author(s):  
Dayna M. Ayers ◽  
Donald J. Bedunah ◽  
Michael G. Harrington
Keyword(s):  
Fuel Consumption ◽  
Pinus Ponderosa ◽  
Ponderosa Pine ◽  
Prescribed Burning ◽  
Selective Logging ◽  
Western Montana ◽  
Fire Damage ◽  
Prescribed Burn ◽  
Large Trees ◽  
Shelterwood Cut

Abstract In many western Montana ponderosa pine (Pinus ponderosa) stands, fire suppression and past selective logging of large trees have resulted in conditions favoring succession to dense stands of shade-tolerant, but insect- and disease-prone Douglas-fir (Pseudotsuga menziesii). Stand thinning and understory prescribed burning have been proposed as surrogates for pre-Euro-American settlement ecological processes and as potential treatments to improve declining forest condition and reduce the probability of severe wildfire. To test the effectiveness of these silvicultural techniques on overstory and understory conditions, research is ongoing in the Lick Creek Demonstration Site in the Bitterroot National Forest, Montana. Our research examined the response (mortality and vigor) of the dominant browse species, antelope bitterbrush (Purshia tridentata) and Scouler's willow (Salix scouleriana), to a ponderosa pine stand restoration project utilizing four treatments: (1) a shelterwood cut that removed 53% of the tree basal area; (2) a shelterwood cut with a low fuel consumption burn; (3) a shelterwood cut with a high fuel consumption burn; and (4) a control. Prior to the application of treatments, 1,856 bitterbrush and 871 willow were located, and their survival and vigor subsequently monitored for 2 yr posttreatment. The cut and burn treatments resulted in the greatest reduction in antelope bitterbrush and Scouler's willow density averaging 66% and 24% of pretreatment density, respectively. The shelterwood cut reduced bitterbrush and Scouler's willow density by 35% and 14%, respectively. On treatments receiving a shelterwood cut (all treatments but the control), but where antelope bitterbrush and Scouler's willow did not have fire damage, mortality was 45% for bitterbrush and 20% for willow, respectively. For bitterbrush and Scouler's willow plants that received fire damage, mortality was 72% for bitterbrush and 19% for willow. Although the burn and shelterwood harvest treatments resulted in reduced density of antelope bitterbrush and Scouler's willow 2 yr posttreatment, these treatments increased vigor of both species and created mineral seedbeds that may be necessary for establishment of seedlings. West. J. Appl. For. 14(3):137-143.

scholarly journals Quantifying pyrodiversity and its drivers

2021 ◽  
Vol 288 (1948) ◽  
Author(s):  
Zachary L. Steel ◽  
Brandon M. Collins ◽  
David B. Sapsis ◽  
Scott L. Stephens
Keyword(s):  
United States ◽  
Human Population ◽  
Fire Regime ◽  
Important Determinant ◽  
Fire Suppression ◽  
Fire Regimes ◽  
Western United States ◽  
Topographic Roughness ◽  
Spatio Temporal ◽  
Ecological Pattern

Pyrodiversity or variation in spatio-temporal fire patterns is increasingly recognized as an important determinant of ecological pattern and process, yet no consensus surrounds how best to quantify the phenomenon and its drivers remain largely untested. We present a generalizable functional diversity approach for measuring pyrodiversity, which incorporates multiple fire regime traits and can be applied across scales. Further, we tested the socioecological drivers of pyrodiversity among forests of the western United States. Largely mediated by burn activity, pyrodiversity was positively associated with actual evapotranspiration, climate water deficit, wilderness designation, elevation and topographic roughness but negatively with human population density. These results indicate pyrodiversity is highest in productive areas with pronounced annual dry periods and minimal fire suppression. This work can facilitate future pyrodiversity studies including whether and how it begets biodiversity among taxa, regions and fire regimes.

scholarly journals Drought Increases Vulnerability of Pinus ponderosa Saplings to Fire-Induced Mortality

Fire ◽  
2020 ◽  
Vol 3 (4) ◽  
pp. 56
Author(s):  
Raquel Partelli-Feltrin ◽  
Daniel M. Johnson ◽  
Aaron M. Sparks ◽  
Henry D. Adams ◽  
Crystal A. Kolden ◽  
...  
Keyword(s):  
Pinus Ponderosa ◽  
Water Status ◽  
Western United States ◽  
Radiative Energy ◽  
Forest Composition ◽  
Fire Intensity ◽  
Surface Fires ◽  
Composition And Structure ◽  
In Fire ◽  
The Impact

The combination of drought and fire can cause drastic changes in forest composition and structure. Given the predictions of more frequent and severe droughts and forecasted increases in fire size and intensity in the western United States, we assessed the impact of drought and different fire intensities on Pinus ponderosa saplings. In a controlled combustion laboratory, we exposed saplings to surface fires at two different fire intensity levels (quantified via fire radiative energy; units: MJ m−2). The recovery (photosynthesis and bud development) and mortality of saplings were monitored during the first month, and at 200- and 370-days post-fire. All the saplings subjected to high intensity surface fires (1.4 MJ m−2), regardless of the pre-fire water status, died. Seventy percent of pre-fire well-watered saplings recovered after exposure to low intensity surface fire (0.7 MJ m−2). All of the pre-fire drought-stressed saplings died, even at the lower fire intensity. Regardless of the fire intensity and water status, photosynthesis was significantly reduced in all saplings exposed to fire. At 370 days post-fire, burned well-watered saplings that recovered had similar photosynthesis rates as unburned plants. In addition, all plants that recovered or attempted to recover produced new foliage within 35 days following the fire treatments. Our results demonstrate that the pre-fire water status of saplings is an important driver of Pinus ponderosa sapling recovery and mortality after fire.

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