- Fire-induced tree mortality
- Fuel and silvicultural treatment effects
- Tree defenses
- Ecosystem resilience
The primary focus of my research is on how fire affects trees and ultimately forest dynamics. My past and current research falls into three broad categories:
- What are the causes and mechanisms of postfire tree mortality? Surprisingly, tree death is still not well understood and therefore hampers efforts to accurately model and predict the impact of disturbance and climate change on tree mortality. My research seeks to understand fire-related factors leading to tree death and the causes of tree mortality. Currently, my research in this area focuses on the impacts of fire and climate on tree carbon allocation patterns to defense, storage, and growth to determine how allocation relates to tree mortality.
- How do changes in fire regimes affect forest succession and forest resilience to climate change and future disturbance? Local fire regimes have been altered in many ecosystems due to direct and indirect anthropogenic activities. Changes in fire frequency and seasonality can cause shifts in species composition and fuel characteristics, which can then impact fire effects through associated changes in fire intensity. Most of my research in this area has focused on the impact of reducing fire frequency in fire-dependent ecosystems. This area of research also examines the effects of silvicultural and fuel treatments to increase understanding of treatment options that foster resilient forests.
- What are the effects of fire on host tree susceptibility to bark beetle attack? Fire can directly impact tree defense and carbon acquisition, which in turn, affects susceptibility to bark beetle attack. Yet fire also can affect stand-level and landscape-level processes such as nutrient and water availability and host tree location. My research examines how fire affects tree defense and ultimately influences the susceptibility of trees to bark beetle attack. Teasing apart the contribution of host tree defenses, stand-level processes, and regional-scale synchrony due to climate on bark beetle population regulation is critical to improve our understanding of outbreaks and how both climate change and management will affect forest susceptibility to bark beetles.
Selected Publications & Products
Understanding Post-fire Tree Mortality: Resources & Research - This StoryMap compiles information about post-fire tree mortality based on past and current research efforts at the U.S. Forest Service Rocky Mountain Research Station, Missoula Fire Sciences Laboratory.
Check out this Research Highlight from the 2017 Association for Fire Ecology Congress about my research on fire and resistance to mountain pine beetle.
Varner, J.M., Hood, S.M., Aubrey, D.P., Yedinak, K., Hiers, J.K., Jolly, W.M., Shearman, T.M., McDaniel, J.K., O’Brien, J.J. and Rowell, E.M. (2021), Tree crown injury from wildland fires: Causes, measurement and ecological and physiological consequences. New Phytol. https://doi.org/10.1111/nph.17539
Hood, Sharon M. 2021. Physiological responses to fire that drive tree mortality. Plant, Cell and Environment. 44(3): 692-695.
Valor, T., S. M. Hood, M. Piqué, A. Larrañaga, and P. Casals. 2021. Resin ducts and bark thickness influence pine resistance to bark beetles after prescribed fire. Forest Ecology and Management 494:119322.
Cansler, C. Alina; Hood, Sharon M.; van Mantgem, Phillip J.; Varner, J. Morgan. 2020. A large database supports the use of simple models of post-fire tree mortality for thick-barked conifers, with less support for other species. Fire Ecology. 16: 25.
Kichas, Nickolas E.; Trowbridge, Amy M.; Raffa, Kenneth F.; Malone, Shealyn C.; Hood, Sharon M.; Everett, Richard G.; McWethy, David B.; Pederson, Gregory T. 2021. Growth and defense characteristics of whitebark pine (Pinus albicaulis) and lodgepole pine (Pinus contorta var latifolia) in a high-elevation, disturbance-prone mixed-conifer forest in northwestern Montana, USA. Forest Ecology and Management. 493: 119286.
Reed, Charlotte C.; Hood, Sharon M. 2021. Few generalizable patterns of tree-level mortality during extreme drought and concurrent bark beetle outbreaks. Science of the Total Environment. 750: 141306.
Fettig, Christopher J.; Hood, Sharon J.; Runyon, Justin B.; Stalling, Chris M. 2021. Bark beetle and fire interactions in western coniferous forests: Research findings. Fire Managment Today. 79(1): 14-23.
Cansler, C. Alina; Hood, Sharon M.; Varner, J. Morgan; van Mantgem, Phillip J.; Agne, Michelle C.; Andrus, Robert A.; Ayres, Matthew P.; Ayres, Bruce D.; Bakker, Jonathan D.; Battaglia, Michael A.; Bentz, Barbara J.; Breece, Carolyn R.; Brown, James K.; Cluck, Daniel R.; Coleman, Tom W.; Corace, R. Gregory; Covington, W. Wallace; Cram, Douglas S.; Cronan, James B.; Crouse, Joseph E.; Das, Adrian J.; Davis, Ryan S.; Dickinson, Darci M.; Fitzgerald, Stephen A.; Fulé, Peter Z.; Ganio, Lisa M.; Grayson, Lindsay M.; Halpern, Charles B.; Hanula, Jim L.; Harvey, Brian J.; Kevin Hiers, J.; Huffman, David W.; Keifer, MaryBeth; Keyser, Tara L.; Kobziar, Leda N.; Kolb, Thomas E.; Kolden, Crystal A.; Kopper, Karen E.; Kreitler, Jason R.; Kreye, Jesse K.; Latimer, Andrew M.; Lerch, Andrew P.; Lombardero, Maria J.; McDaniel, Virginia L.; McHugh, Charles W.; McMillin, Joel D.; Moghaddas, Jason J.; O’Brien, Joseph J.; Perrakis, Daniel D. B.; Peterson, David W.; Prichard, Susan J.; Progar, Robert A.; Raffa, Kenneth F.; Reinhardt, Elizabeth D.; Restaino, Joseph C.; Roccaforte, John P.; Rogers, Brendan M.; Ryan, Kevin C.; Safford, Hugh D.; Santoro, Alyson E.; Shearman, Timothy M.; Shumate, Alice M.; Sieg, Carolyn H.; Smith, Sheri L.; Smith, Rebecca J.; Stephenson, Nathan L.; Stuever, Mary; Stevens, Jens T.; Stoddard, Michael T.; Thies, Walter G.; Vaillant, Nicole M.; Weiss, Shelby A.; Westlind, Douglas J.; Woolley, Travis J.; Wright, Micah C. 2020. The Fire and Tree Mortality Database, for empirical modeling of individual tree mortality after fire. Scientific Data. 7: 194.
Hood, Sharon M.; Keyes, Christopher R.; Bowen, Katelynn J.; Lutes, Duncan C.; Seielstad, Carl. 2020. Fuel treatment longevity in ponderosa pine-dominated forest 24 years after cutting and prescribed burning. Frontiers in Forests and Global Change. 3: Article 78.
Describes how to reintroduce fire in areas with deep duff to reduce tree mortality.
This photoseries documents changes in a ponderosa pine forest from 1909 to 2015.
A general overview of how fire kills trees.