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55. Invigorating Prescribed Fire Science Through Improved Reporting Practices

Author

Bonner, Sophie R., primary, Hoffman, Chad M., additional, Kane, Jeffrey M., additional, Varner, J. Morgan, additional, Hiers, J. Kevin, additional, O’Brien, Joseph J., additional, Rickard, Heather D., additional, Tinkham, Wade T., additional, Linn, Rodman R., additional, Skowronski, Nicholas, additional, Parsons, Russell A., additional, and Sieg, Carolyn H., additional

Published
2021
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59. The influence of fuelbed properties on moisture drying rates and timelags of longleaf pine litter

Author

Nelson, Jr., Ralph M. and Hiers, J. Kevin

Subjects
Forest fire research, Fuel -- Properties -- Evaluation, Moisture -- Evaluation, Earth sciences, Evaluation, Properties
Abstract

Fire managers often model pine needles as 1 h timelag fuels, but fuelbed properties may significantly change the rate at which needles exchange moisture with the atmosphere. The problem of determining whether moisture loss from fine fuels is being controlled by individual particles or by the fuelbed remains unresolved. Results from this laboratory experiment indicate that first-period timelags of longleaf pine (Pinus palustris Mill.) needles are altered by fuelbed loading and needle arrangement. Timelags of individual needles ranged from 3.3 to 5.3 h; timelags of beds of vertically oriented needles (4.4 to 8.6 h) approximated those of individual particles, but were slightly influenced by loading. Beds of horizontal needles dried with load-dependent timelags that varied from 6.5 to 31.6 h. Fuel loads ranged from 0.04 (for individual particles) to 1.07 kg x [m.sup-2]. We report a new metric, the area drying rate, which is analogous to a unit-area burning rate. For beds of flat needles, plots of the area drying rate versus fuel load illustrate a transition from control by individual particles to control by the bed structure when fuel loading is approximately 0.33 kg x [m.sup.-2]. Beds of vertical needles were particle controlled. Results should be useful to fire managers when modeling fire behavior. Les gestionnaires du feu modelisent souvent les aiguilles de pin en assumant qu'il s'agit d'un combustible dont le temps de sechage est d'une heure mais les proprietes des couches de combustibles peuvent modifier de facon significative le taux d'echange d'humidite des aiguilles avec l'atmosphere. La question qui consiste a savoir a quel moment la perte d'humidite des combustibles legers est determinee par les particules individuelles ou la couche de combustibles demeure sans reponse. Les resultats de cette experience en laboratoire indiquent que le temps de sechage de la premiere periode des aiguilles de pin des marais (Pinus palustris Mill.) est influence par la charge de la couche de combustibles et l'arrangement des aiguilles. Le temps de sechage des aiguilles individuelles varie de 3,3 a 5,3 h; le temps de sechage des couches de combustibles o les aiguilles sont orientees verticalement correspond approximativement a celui des particules individuelles mais il est legerement influence par la charge de combustibles. Les couches de combustibles o les aiguilles sont placees a l'horizontal ont un temps de sechage de 6,5 a 31,6 h dependamment de la charge de combustibles. La charge de combustibles varie de 0,04 (pour les particules individuelles) a 1,07 kg-[m.sup.-2]. Nous presentons une nouvelle mesure, la vitesse de sechage en surface, qui est analogue a la vitesse de combustion en surface. Pour les couches de combustibles o les aiguilles sont a plat, la representation graphique de la vitesse de sechage en surface en fonction de la charge de combustibles illustre la transition entre le moment o la perte d'humidite est determinee par les particules individuelles et celui o elle est determinee par la structure de la couche de combustibles lorsque la charge de combustibles atteint approximativement 0,33 kg x [m.sup.-2]. Dans les couches de combustibles o les aiguilles sont placees a la verticale, la perte d'humidite est determinee par les particules. Les resultats devraient etre utiles aux gestionnaires du feu pour modeliser le comportement du feu. [Traduit par la Redaction], Introduction Moisture exchange between fine dead fuels and the atmosphere is a fundamental process affecting fire behavior predictions, but the influence of fuelbed structure on the rate of exchange remains [...]

Published
2008

60. Overstory tree mortality resulting from reintroducing fire to long-unburned longleaf pine forests: the importance of duff moisture

Author

Varner, III, J. Morgan, Hiers, J. Kevin, Ottmar, Roger D., Gordon, Doria R., Putz, Francis E., and Wade, Dale D.

Subjects
Forest fire research, Mortality -- Canada -- Evaluation, Longleaf pine -- Properties, Forest fires -- Canada -- Influence, Earth sciences, Influence, Evaluation, Properties
Abstract

Abstract: In forests historically maintained by frequent fire, reintroducing fire after decades of exclusion often causes widespread overstory mortality. To better understand this phenomenon, we subjected 16 fire-excluded (ca. 40 [...]

Published
2007

61. Competitive responses of seedlings and understory plants in longleaf pine woodlands: separating canopy influences above and below ground

Author

Pecot, Stephen D., Mitchell, Robert J., Palik, Brian J., Moser, E. Barry, and Hiers, J. Kevin

Subjects
Forest flora -- Growth, Plant competition -- Observations -- Growth, Seedlings -- Growth, Plant canopies -- Observations -- Growth, Earth sciences, Company growth, Observations, Growth
Abstract

Abstract: A trenching study was used to investigate above- and below-ground competition in a longleaf pine (Pinus palustris P. Mill.) woodland. Trenched and nontrenched plots were replicated in the woodland [...]

Published
2007

64. Pyrodiversity promotes pollinator diversity in a fire‐adapted landscape.

Author

Ulyshen, Michael D, Hiers, J Kevin, Pokswinksi, Scott M, and Fair, Conor

Subjects
FIRE management, POLLINATORS, FLORIDA state history, PLANT diversity, LANDSCAPES, BEES, BUTTERFLIES
Abstract

Fire is a key determinant of vegetation structure and composition in ecosystems worldwide and is therefore an important management tool. The "pyrodiversity hypothesis", which postulates that biodiversity will increase as fire diversity increases, remains largely untested for pollinators, a group of high conservation concern. We tested the relationship between pollinator diversity and pyrodiversity based on a decade of burn history in Florida, as well as testing other parameters, including burn frequency, the percentage of area burned during the year of sampling, canopy openness, and various plant metrics. Both bees and butterflies responded positively to pyrodiversity and to the percentage of area burned during the year of sampling. In addition, our results indicate that pollinators, especially butterflies, may be sensitive to high burn frequency. Our findings reveal the important role fire history plays in shaping pollinator communities and demonstrate that increasing burn heterogeneity can benefit this fauna in fire‐managed landscapes. [ABSTRACT FROM AUTHOR]

Published
2022
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73. Quantifying carbon and species dynamics under different fire regimes in a southeastern U.S. pineland

Author

Flanagan, Steven A., primary, Bhotika, Smriti, additional, Hawley, Christie, additional, Starr, Gregory, additional, Wiesner, Susanne, additional, Hiers, J. Kevin, additional, O'Brien, Joseph J., additional, Goodrick, Scott, additional, Callaham, Mac A., additional, Scheller, Robert M., additional, Klepzig, Kier D., additional, Taylor, R. Scott, additional, and Loudermilk, E. Louise, additional

Published
2019
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83. Allometry of the pyrophytic Aristida in fire‐maintained longleaf pine–wiregrass ecosystems.

Author

Shearman, Timothy M., Varner, J. Morgan, Robertson, Kevin, and Hiers, J. Kevin

Subjects
ARISTIDA, BIOMASS, SAVANNAS
Abstract

Premise of the Study: Aboveground biomass (AGB) of herbaceous vegetation is a primary source of fuel in frequent surface fires that maintain grasslands, savannas, and woodlands. Methods for nondestructively estimating AGB are required to understand the mechanisms by which fuels affect fire behavior and the effects of time since the last burn. We developed allometric equations to estimate AGB in wiregrass (Aristida beyrichiana/A. stricta), a dominant bunchgrass in Pinus palustris ecosystems and a key species for ecological restoration. Methods: We collected wiregrass from North Carolina to Florida, across a range of time‐since‐last burn and site types. We tested 32 mixed effect models to see which predictors were best at predicting live, dead, and total AGB. We also examined how time since burn (TSB) affected the live‐to‐dead ratio (LDR) using regression. Key Results: Wiregrass AGB was found to increase with increasing latitude (relative to tussock volume), possibly due to an increase in precipitation, and was greater on more fertile clay soils and flatwoods than on sandy soils. The LDR decreased as a power function with TSB, resulting in rapid accumulation of dead, highly flammable, biomass in the fire‐free period. Conclusions: Greater biomass will support fires of higher intensity. Our models can be useful in the parameterization of future physics‐based models to predict fire behavior. Understanding the environmental variables that influence the allometry of wiregrass should help increase the precision of AGB estimates and the subsequent effects on fire behavior and effects on neighboring vegetation. [ABSTRACT FROM AUTHOR]

Published
2019
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84. Suites of Fire-Adapted Traits of Oaks in the Southeastern USA: Multiple Strategies for Persistence

Author

Forest Resources and Environmental Conservation, Varner, J. Morgan, Kane, Jeffrey M., Hiers, J. Kevin, Kreye, Jesse K., Veldman, Joseph W., Forest Resources and Environmental Conservation, Varner, J. Morgan, Kane, Jeffrey M., Hiers, J. Kevin, Kreye, Jesse K., and Veldman, Joseph W.

Abstract

Fire is integral to the functioning of terrestrial ecosystems of the southeastern USA and is a strong selective force on plant species. Among woody plants, oak species (Quercus spp. L) have diverse life history traits that appear to reflect their evolution in this fire-prone region. Oaks also occur across wide gradients of fire frequency and intensity, from annually burned savannas to fire-protected forests. As such, oak functional traits are presumed to reflect adaptations to acquire limited resources (i.e., "physiological traits") or survive environmental stress (i.e., "protective traits"). Oak functional traits may also influence fire regimes (i.e., via "flammability traits") by altering fire behavior through effects on fuels and their combustion. We synthesized evidence from ecophysiological measurements, laboratory burning and drying experiments, and field experiments to determine the suites of functional traits that reflect fire adaptive strategies in eight Southeastern oaks for which abundant data were available. We found strong correlations among Principal Components Analysis axes for flammability (litter burning and drying), protective (bark and wound responses), and physiological (growth) traits. The eight oaks clustered into three strategies: 1) pyrophytic species that produce highly flammable leaf litter, accrue thick bark rapidly, close wounds rapidly, and grow slowly; 2) mesophytic species that produce low flammability litter, have thin bark, and are fast growing; and 3) fire-avoider species with a mixture of traits from the two extremes. This synthesis clarifies the relative pyrophily of Southeastern oaks and suggests how suites of fire-related traits influence fire regimes and species habitat preferences.

Published
2016

86. Canopy-Derived Fuels Drive Patterns of In-Fire Energy Release and Understory Plant Mortality in a Longleaf Pine (Pinus palustris) Sandhill in Northwest Florida, USA

Author

O’Brien, Joseph J., primary, Loudermilk, E. Louise, additional, Hiers, J. Kevin, additional, Pokswinski, Scott M., additional, Hornsby, Benjamin, additional, Hudak, Andrew T., additional, Strother, Dexter, additional, Rowell, Eric, additional, and Bright, Benjamin C., additional

Published
2016
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87. Imputation of Individual Longleaf Pine (Pinus palustrisMill.) Tree Attributes from Field and LiDAR Data

Author

Silva, Carlos A., primary, Hudak, Andrew T., additional, Vierling, Lee A., additional, Loudermilk, E. Louise, additional, O’Brien, Joseph J., additional, Hiers, J. Kevin, additional, Jack, Steve B., additional, Gonzalez-Benecke, Carlos, additional, Lee, Heezin, additional, Falkowski, Michael J., additional, and Khosravipour, Anahita, additional

Published
2016
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91. Fire weather conditions and fire–atmosphere interactions observed during low-intensity prescribed fires – RxCADRE 2012

Author

Clements, Craig B., primary, Lareau, Neil P., additional, Seto, Daisuke, additional, Contezac, Jonathan, additional, Davis, Braniff, additional, Teske, Casey, additional, Zajkowski, Thomas J., additional, Hudak, Andrew T., additional, Bright, Benjamin C., additional, Dickinson, Matthew B., additional, Butler, Bret W., additional, Jimenez, Daniel, additional, and Hiers, J. Kevin, additional

Published
2016
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93. Fire emission uncertainties and their effect on smoke dispersion predictions: a case study at Eglin Air Force Base, Florida, USA

Author

Davis, Aika Y., primary, Ottmar, Roger, additional, Liu, Yongqiang, additional, Goodrick, Scott, additional, Achtemeier, Gary, additional, Gullett, Brian, additional, Aurell, Johanna, additional, Stevens, William, additional, Greenwald, Roby, additional, Hu, Yongtao, additional, Russell, Armistead, additional, Hiers, J. Kevin, additional, and Odman, M. Talat, additional

Published
2015
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100. Imputation of Individual Longleaf Pine ( Pinus palustris Mill.) Tree Attributes from Field and LiDAR Data.

Author

Silva, Carlos A., Hudak, Andrew T., Vierling, Lee A., Loudermilk, E. Louise, O’Brien, Joseph J., Hiers, J. Kevin, Jack, Steve B., Gonzalez-Benecke, Carlos, Lee, Heezin, Falkowski, Michael J., and Khosravipour, Anahita

Subjects
LONGLEAF pine, FOREST surveys, OPTICAL radar
Abstract

Copyright of Canadian Journal of Remote Sensing is the property of Taylor & Francis Ltd and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Published
2016
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