Validating the Malheur model for predicting ponderosa pine post-fire mortality using 24 fires in the Pacific Northwest, USA

2012 ◽  
Vol 21 (5) ◽  
pp. 572 ◽  
Author(s):  
Walter G. Thies ◽  
Douglas J. Westlind

Fires, whether intentionally or accidentally set, commonly occur in western interior forests of the US. Following fire, managers need the ability to predict mortality of individual trees based on easily observed characteristics. Previously, a two-factor model using crown scorch and bole scorch proportions was developed with data from 3415 trees for predicting the probability of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) mortality following prescribed fire. Here, we report validation of that model for broader application using data from 10 109 ponderosa pines in 17 prescribed fires and 7 wildfires, observed for 3 years post-fire, from east of the Cascade Range crest in Washington, Oregon and northern California. The overall rate of correct classification was 87.1% and the rate of correctly predicting mortality was 80.1%. Similar accuracy is reported when testing the model for small trees (<53.3-cm diameter at breast height), wildfire, prescribed fire, and when using a field guide that simplifies application of the model. For large trees (≥53.3-cm diameter at breast height), the overall rate of correct prediction was 93.6% and the rate of correctly predicting mortality was 65.2%. These results suggest the Malheur model is useful for predicting ponderosa pine mortality following fires in this region.

2008 ◽  
Vol 38 (5) ◽  
pp. 919-923 ◽  
Author(s):  
Martin W. Ritchie ◽  
Brian M. Wing ◽  
Todd A. Hamilton

Ponderosa pine ( Pinus ponderosa Dougl. ex P. & C. Laws.) stands with late-seral features are found infrequently, owing to past management activities throughout western North America. Thus, management objectives often focus on maintaining existing late-seral stands. Observations over a 65 year period of stands with no past history of harvest showed substantial ingrowth in the smaller diameter classes and elevated rates of mortality among the largest mature trees in the stand. Adjacent stands, with combinations of thinning and prescribed fire, had far fewer high-risk mature trees and generally lower rates of mortality after treatment. Forecasts using individual-tree diameter growth and mortality models suggest that observed declines in these stands with remaining old trees and a dense understory will continue in the absence of any treatment. Increased vigor in thinned stands appeared to be offset by an increase in mortality of large trees when thinning was followed by prescribed fire.


2008 ◽  
Vol 23 (4) ◽  
pp. 197-201 ◽  
Author(s):  
Geoffrey H. Donovan ◽  
Thomas C. Brown

Abstract Although the importance of wildfire to fire-adapted ecosystems is widely recognized, wildfire management has historically placed less emphasis on the beneficial effects of wildfire. We estimate the avoided fuel treatment cost for 10 ponderosa pine (Pinus ponderosa) stands on the Umatilla National Forest in the Pacific Northwest. Results show that fires in stands that show the greatest divergence from the archetypical ponderosa pine stand structure (large trees in an open, parklike stand) tend to have higher avoided costs. This is a reflection of the higher cost of fuel treatments in these stands: treatments designed to restore a stand to a desired condition are normally more expensive than treatments to maintain a stand in a desired condition.


2008 ◽  
Vol 38 (4) ◽  
pp. 844-850 ◽  
Author(s):  
Gregory Peters ◽  
Anna Sala

Thinning and thinning followed by prescribed fire are common management practices intended to restore historic conditions in low-elevation ponderosa pine ( Pinus ponderosa Dougl. ex P. & C. Laws.) forests of the northern Rocky Mountains. While these treatments generally ameliorate the physiology and growth of residual trees, treatment-specific effects on reproductive output are not known. We examined reproductive output of second-growth ponderosa pine in western Montana 9 years after the application of four treatments: thinning, thinning followed by spring prescribed fire, thinning followed by fall prescribed fire, and unthinned control stands. Field and greenhouse observations indicated that reproductive traits vary depending on the specific management treatment. Cone production was significantly higher in trees from all actively managed stands relative to control trees. Trees subjected to prescribed fire produced cones with higher numbers of filled seeds than trees in unburned treatments. Seed mass, percentage germination, and seedling biomass were significantly lower for seeds from trees in spring burn treatments relative to all others and were generally higher in trees from fall burn treatments. We show for the first time that thinning and prescribed-burning treatments can influence reproductive output in ponderosa pine.


2003 ◽  
Vol 33 (5) ◽  
pp. 870-884 ◽  
Author(s):  
Rick G Kelsey ◽  
Gladwin Joseph

Sixteen days after a September wildfire, ethanol and water were measured in phloem and sapwood at breast height and the base of Pinus ponderosa Dougl. ex P. & C. Laws. with zero (control), moderate, heavy, and severe crown scorch. The quantity of ethanol increased with each level of injury, resulting in trees with severe scorch containing 15 and 53 times more phloem and sapwood ethanol, respectively, than controls. Ethanol concentrations in the sapwood and adjacent phloem were related, probably as a result of diffusion. Upward movement in xylem sap was most likely responsible for the relationship between sapwood ethanol concentrations at breast height and the stem base. As trees recovered from their heat injuries, the ethanol concentrations declined. In contrast, ethanol accumulated in dead trees that lost their entire crowns in the fire. Various bark and xylophagous beetles landed in greater numbers on fire-damaged trees than on controls the following spring and summer, suggesting that ethanol was being released to the atmosphere and influencing beetle behavior. Beetle landing was more strongly related to sapwood ethanol concentrations the previous September than in May. Sapwood ethanol measured 16 days after the fire was the best predictor of second-year mortality for trees with heavy and severe crown scorch.


1999 ◽  
Vol 14 (3) ◽  
pp. 137-143 ◽  
Author(s):  
Dayna M. Ayers ◽  
Donald J. Bedunah ◽  
Michael G. Harrington

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.


2008 ◽  
Vol 38 (5) ◽  
pp. 924-935 ◽  
Author(s):  
Christopher J. Fettig ◽  
Robert R. Borys ◽  
Stephen R. McKelvey ◽  
Christopher P. Dabney

Mechanical thinning and the application of prescribed fire are commonly used tools in the restoration of fire-adapted forest ecosystems. However, few studies have explored their effects on subsequent amounts of bark beetle caused tree mortality in interior ponderosa pine, Pinus ponderosa Dougl. ex P. & C. Laws. var. ponderosa. In this study, we examined bark beetle responses to creation of midseral (low diversity) and late-seral stages (high diversity) and the application of prescribed fire on 12 experimental units ranging in size from 76 to 136 ha. A total of 9500 (5.0% of all trees) Pinus and Abies trees died 2 years after treatment of which 28.8% (2733 trees) was attributed to bark beetle colonization. No significant difference in the mean percentage of trees colonized by bark beetles was found between low diversity and high diversity. The application of prescribed fire resulted in significant increases in bark beetle caused tree mortality (all species) and for western pine beetle, Dendroctonus brevicomis LeConte, mountain pine beetle, Dendroctonus ponderosae Hopkins, Ips spp., and fir engraver, Scolytus ventralis LeConte, individually. Approximately 85.6% (2339 trees) of all bark beetle caused tree mortality occurred on burned split plots. The implications of these and other results to sustainable forest management are discussed.


2013 ◽  
Vol 24 (2) ◽  
pp. 138-151 ◽  
Author(s):  
RAFAEL BARRIENTOS ◽  
BERNARDO ARROYO

SummaryInvestigating habitat selection is a key step in improving the population conservation of forest species in areas managed for different purposes, from timber harvesting to hunting or recreation. Because economic resources allocated to conservation are limited, studies that assess cost-effective strategies are necessary, especially when concerning non-threatened species. We studied nest-site habitat selection of two raptor communities (totalling 245 nests from the five most common species: Short-Toed Eagle Circaetus gallicus, Goshawk Accipiter gentilis, Sparrowhawk A. nisus, Common Buzzard Buteo buteo and Booted Eagle Aquila pennata) in two pinewoods in central Spain separated by 200 km. Using a Generalised Linear Mixed Model for each species and with locality as a random factor, we obtained five models of habitat selection. We highlighted the common nesting patterns in order to facilitate an integrated management of forestry in relation to raptor nesting habitat selection. The most important variable for all species, with the exception of the Sparrowhawk was the nest-tree diameter at breast height, with raptors preferentially selecting nesting trees of large width. Tall trees and a high amount of tree cover around the nesting tree were also important habitat features for several species. Our results suggest that pinewoods should retain unharvested patches with moderate tree coverage (30–70%) containing not only several large trees (diameter at breast height > 40 cm) but also small ones. At the landscape level, open forests and heterogeneous habitats are preferred. These forest patches should be dispersed throughout the landscape.


2012 ◽  
Vol 27 (1) ◽  
pp. 36-41 ◽  
Author(s):  
Alicia L. Reiner ◽  
Nicole M. Vaillant ◽  
Scott N. Dailey

Abstract The purpose of this study was to provide land managers with information on potential wildfire behavior and tree mortality associated with mastication and masticated/fire treatments in a plantation. Additionally, the effect of pulling fuels away from tree boles before applying fire treatment was studied in relation to tree mortality. Fuel characteristics and tree mortality data were gathered before and after treatments in a 25-year-old ponderosa pine (Pinus ponderosa C. Lawson) plantation. A random block design was used with three treatments plus a control at each of four blocks. Four plots were established as subsamples within each of the treatment and control sections of each block. Potential wildfire behavior for posttreatment fuel conditions was modeled for 90th and 97th percentile fire weather. Predicted rates of spread and flame lengths were higher for fuel conditions resulting from the mastication treatments than for the masticated/fire treatments or the controls. Torching and crowning indices indicated that higher windspeeds would be necessary to promote torching for areas treated with mastication/fire than for mastication or the controls. Tree mortality was 32 and 17% the first year after burning in masticated/fire and masticated/pull-back/fire plots, respectively, and 49 and 27% the second year. Our potential wildfire behavior results indicate that the risk of crown fire can be somewhat reduced by mastication and further reduced if mastication is followed up with prescribed fire to consume surface fuels. However, moderate levels of tree mortality seem inevitable when burning masticated fuels in a plantation and may only marginally be reduced by pulling fuels away from tree boles, which increases treatment costs.


1991 ◽  
Vol 1 (2) ◽  
pp. 107 ◽  
Author(s):  
KC Ryan ◽  
WH Frandsen

Fuel accumulations were measured in duff mounds around the bases of 19 mature Pinus ponderosa Laws. (ponderosa pine) in a 200-year-old stand in Glacier National Park, Montana. Tree diameter at breast height ranged from 50 to 114 cm (mean = 80 cm). The stand burned at intervals between 13 to 58 years prior to European settlement. This stand had not burned for 69 years. The duff depth 30 cm from the tree bole ranged from 3 to 39 cm (mean = 18 cm). Duff depth increased with tree diameter and decreased with distance from the bole. Duff depth 90 cm from the bole averaged one-half the depth 30 cm from the bole. Duff consumption and its effect on cambium mortality were quantified following a late summer, low intensity fire. Duff moisture contents on a dry weight basis were: fermentation (20%) and humus (36%). Smoldering combustion consumed98% of the duff beneath the trees. Two patterns of duff burning were documented: downward spreading and lateral spreading. Temperatures near the root crown were above 300�C for 2 to 4 hours, resulting in mortality of 45% of the cambium samples (n = 76) tested at the root crown. The probability of cambium mortality increased with duff depth and tree diameter. However, cambium mortality was lower than expected from analysis of thermal diffusion through bark. Cooling by mass transport through phloem and xylem is suggested as apossible explanation for the low cambium mortality.


2007 ◽  
Vol 37 (10) ◽  
pp. 1854-1866 ◽  
Author(s):  
Heather T. Root ◽  
Gregory G. McGee ◽  
Ralph D. Nyland

We sampled epiphytic lichen communities in nine Adirondack northern hardwood stands: three old growth, three reserve shelterwood, and three single-tree selection systems. Our objectives were to assess the effects of treatment, tree diameter at breast height, and their interaction on lichen communities and to determine whether lichen traits were associated with particular habitats. Lichen community composition was strongly related to tree diameter at breast height and differed between old growth and reserve shelterwoods. Lichen community composition was also related to an interaction between tree size and stand type. Lobaria pulmonaria (L.) Hoffm. was associated with large trees in old growth, whereas Evernia mesomorpha Nyl., Parmelia sulcata Taylor, and Physcia millegrana Degel. characterized those in shelterwood stands. Nitrophilous lichens were most common on small trees and in reserve shelterwoods, whereas small trees in selection systems and old growth supported lichens that were found to be most associated with larger trees overall. Selection systems apparently maintained lichen communities indistinguishable from those in old growth or reserve shelterwood. Because large trees hosted unique epiphyte assemblages particularly rich in fruticose and cyanolichen species, we expect that management retaining few or no large trees will alter epiphytic lichen communities.


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