Basal Injury From Smoldering Fires in Mature Pinus ponderosa Laws

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.

Author(s):  
Michael Jenkins

The major objective of this ongoing study is to document vegetative changes resulting from alteration of the fire regime in the mixed conifer/aspen communities of Bryce Canyon National Park. Previous fire history studies have documented fire return intervals using fire scar analysis of ponderosa pine Pinus ponderosa in the park (Buchannan and Tolman 1983: Wight 1989) and for the Paunsaugunt Plateau (Stein 1988). Numerous other studies have similarly documented the fire regime in pre-European settlement ponderosa pine forests in western North America. The study is being conducted in the more mesic mixed conifer communities at the south end of Bryce Canyon National Park and will specifically document vegetative changes suggested by Roberts et al. (1992) resulting from suppression of frequent low intensity surface fires and overgrazing.


2001 ◽  
Vol 16 (1) ◽  
pp. 18-21 ◽  
Author(s):  
Daniel W. Omdal ◽  
William R. Jacobi ◽  
Charles G. Shaw

Abstract An important component of forest ecosystems in the southern Rocky Mountains is the belowground biomass associated with mature stands of ponderosa pine (Pinus ponderosa). Information on root biomass is fundamental to understanding the dynamics of ecological systems and designing studies of those systems. Ponderosa pine trees from a stand in northern New Mexico were cut and their root systems excavated. Biomass of all roots > 0.6 cm in diameter and the belowground portion of the stump was determined on a dry-weight basis. A regression model was constructed using data on breast-height diameter and belowground stump and coarse-root biomass from 42 trees in the stand. Diameter at breast height ranged from 18.3 to 67.6 cm, and belowground biomass ranged from 3 to 576 kg. West. J. Appl. For. 16(1):18–21.


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.


1989 ◽  
Vol 4 (2) ◽  
pp. 58-59 ◽  
Author(s):  
Gregory M. Filip ◽  
Donald J. Goheen ◽  
David W. Johnson ◽  
John H. Thompson

Abstract A naturally regenerated stand of ponderosa pine (Pinus ponderosa) was thinned in 1966 to determine the effects of spacing on crop-tree mortality caused by Armillaria root disease in central Oregon. After 20 years, crop-tree mortality in unthinned plots exceeded that in the thinned plots (1.6 vs. 0.8 trees/ac/yr). Crop-tree diameter growth, however, was greater in thinned plots (0.2 vs. 0.1 in./yr). Forest managers should not defer thinning of similar stands because of Armillaria root disease. West J. Appl. For. 4(2):58-59, April 1989.


1976 ◽  
Vol 108 (7) ◽  
pp. 693-699 ◽  
Author(s):  
Judy Bodenham ◽  
Robert E. Stevens ◽  
T. O. Thatcher

AbstractConotrachelus neomexicanus Fall occurs throughout the range of Pinus ponderosa Laws. in the central and southwestern United States. It is commonly found infesting ponderosa pine cones in north-central Colorado. C. neomexicanus is univoltine. Eggs are laid in second-year cones from May through July. Larvae mine extensively in the cones and drop to the ground for pupation in the soil. Adults emerge from the soil in late summer and early fall, return to the trees to feed on twigs, and presumably hibernate in sheltered locations during the winter A tachinid fly, Myiophasia sp. nr. ruficornis Tns., is an internal parasitoid of weevil larvae.


Author(s):  
F. Gartner ◽  
E. White ◽  
L. Worcester

The study was designed to determine whether different fuel and soil moisture levels at time of ignition would alter the response of key grass species to prescribed burning. Grasslands occupy approximately 75% of the area of Wind Cave National Park (WCNP); the remainder is dominated by ponderosa pine (Pinus ponderosa), according to Lovass (1973). The Soil Conservation Service (1969) classed only about 17% of the Park area as woodland. Nearly all grassland adjacent to woodland has been invaded by ponderosa pine. Almost without exception, pine invades the little bluestem - big bluestem (Schizachyrium scorparium - Andropogon gerardi) community, but not the wheatgrass - needle-grass - grama (Andropogon - Stipa- Bouteloua) community. While these two communities are frequently interspersed, the bluestem community probably occupies the largest percentage of the total grassland area. The general relationships between fuel moisture content and fire spread (or ease of control) are well known. However, relationships between fuel and surface soil moisture content and responses of plant species to burning are not well documented. Since the key grass species of the bluestem community are major dominants throughout the Park, that community was selected for the study. Examined were the effects of three fuel moisture levels (dry, medium and wet) at ignition on postburn species composition, cover, height, weight, soil moisture and soil chemistry. The design also included an unburned (control) treatment.


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.


1988 ◽  
Vol 3 (4) ◽  
pp. 123-125 ◽  
Author(s):  
J. P. McTague ◽  
W. F. Stansfield

Abstract Total outside and inside bark cubic foot volume equations are presented for southwestern ponderosa pine (Pinus ponderosa) that are functions of total tree height, diameter breast height, and Girard form class. These equations are appropriate for trees of any size or age, and no distinction is made between "blackjack" and "yellow pine" trees. Equations are included to predict merchantable volume to any upper stem diameter or merchantable height. Taper and merchantable height functions are indirectly derived from the merchantable volume equations. West. J. Appl For. 3(4):123-125, October 1988.


2019 ◽  
Vol 49 (10) ◽  
pp. 1320-1328
Author(s):  
David R. Weise ◽  
Stephen S. Sackett ◽  
Sally M. Haase ◽  
Nels Johnson

Ambient soil temperatures were measured every four weeks from May 1986 to November 1986 at three depths under the organic forest floor in ponderosa pine (Pinus ponderosa Lawson & C. Lawson) forests in three stand types subjected to periodic prescribed burning. Temperatures at the organic layer – soil surface interface in sawtimber stands were higher and more variable than in pole and saplings stands. Temperature variability reached a maximum in the summer and decreased into the fall and early winter. Soil temperature variability decreased as depth below the surface increased. Three years after the low-intensity prescribed burns, soil temperatures in the burned stands were not significantly different from the those in the unburned controls, suggesting that any effect, though none was detected, of the low-intensity prescribed burns on soil temperature and belowground processes affected by temperature is short-lived in these stands.


Fire Ecology ◽  
2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Shawn T. McKinney

Abstract Background Forest management, especially restoration, is informed by understanding the dominant natural disturbance regime. In many western North American forests, the keystone disturbance is fire, and a plethora of research exists characterizing various fire regime parameters, although often only one or two parameters are addressed in individual studies. I performed a systematic review of the literature and meta-analysis of the derived data from 26 publications to characterize five parameters of the historical fire regime of ponderosa pine (Pinus ponderosa Lawson & C. Lawson) ecosystems in Colorado, USA: fire frequency, severity, extent, seasonality, and climate. Results The collection of evidence indicates a fire regime predominantly characterized by moderate to high frequency, low- and mixed-severity fires that occurred in late summer to fall, with fires occurring in drier than average years that were often preceded by two to three years of wetter than average conditions. The overall average mean fire return interval (MFI) was 21 years (SD = 1.4 years, n = 78 sites) and increased with site elevation (r = 0.33, P < 0.05). Low- and mixed-severity fires accounted for 83% of all observations, and 69% of fires occurred in late summer to fall with no relationship found between latitude and seasonality. Geographic region (Front Range and southwestern Colorado) was associated with variability in fire regime parameter values, with southwestern Colorado sites having a stronger association with wetter than average conditions in the three years preceding fire years and a shorter mean MFI (18 years) relative to Front Range sites (23 years). Data were insufficient to evaluate changes in fire severity and extent due to a lack of historical information, as well as differences in sampling methods and reporting. Conclusion This meta-analytic approach identified variation within and among fire regime parameter values that occurred along elevational and geographic axes, and this information should be useful to managers engaging in forest restoration aimed at enhancing resilience of fire-adapted forests to disturbance and climate change.


Sign in / Sign up

Export Citation Format

Share Document