Landscape Ecology

, Volume 31, Issue 3, pp 619–636 | Cite as

Fire legacies impact conifer regeneration across environmental gradients in the U.S. northern Rockies

  • Kerry B. KempEmail author
  • Philip E. Higuera
  • Penelope Morgan
Research Article



An increase in the incidence of large wildfires worldwide has prompted concerns about the resilience of forest ecosystems, particularly in the western U.S., where recent changes are linked with climate warming and 20th-century land management practices.


To study forest resilience to recent wildfires, we examined relationships among fire legacies, landscape features, ecological conditions, and patterns of post-fire conifer regeneration.


We quantified regeneration across 182 sites in 21 recent large fires in dry mixed-conifer forests of the U.S. northern Rockies. We used logistic and negative binomial regression to predict the probability of establishment and abundance of conifers 5–13 years post-fire.


Seedling densities varied widely across all sites (0–127,500 seedlings ha−1) and were best explained by variability in distance to live seed sources (β = −0.014, p = 0.002) and pre-fire tree basal area (β = 0.072, p = 0.008). Beyond 95 m from the nearest live seed source, the probability of seedling establishment was low. Across all the fires we studied, 75 % of the burned area with high tree mortality was within this 95-m threshold, suggesting the presence of live seed trees to facilitate natural regeneration.  


Combined with the mix of species present within the burn mosaic, dry mixed-conifer forests will be resilient to large fires across our study region, provided that seedlings survive, fire do not become more frequent, high-severity patches do not get significantly larger, and post-fire climate conditions remain suitable for seedling establishment and survival.


Tree regeneration Mixed-severity Wildfire Patch size Distance to seed source Resilience 



We thank K. Baker, M. Chaney, and A. Wells for assistance with data collection, S. Busby, R. Ramsey, and O. Guthrie for assistance with data collection and entry, Tim Johnson for helpful insights and assistance with statistical analysis, Zack Holden for providing the R script for calculating the distances to patch edges, and John Abatzoglou for providing downscaled climate data. This work was supported by grants from the National Aeronautics and Space Administration under award NNX11AO24G (PM), the National Science Foundation under awards DGE-0903479 (PM, KBK) and IIA-0966472 (PEH), the Joint Fire Science Program Graduate Research Innovation program under award 12-3-1-13 (KBK, PEH), and the University of Idaho Stillinger Trust Forest Science fellowship (KBK).

Supplementary material

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10980_2015_268_MOESM2_ESM.docx (470 kb)
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Copyright information

© Springer Science+Business Media Dordrecht 2015

Authors and Affiliations

  1. 1.College of Natural ResourcesUniversity of IdahoMoscowUSA
  2. 2.Department of Ecosystem and Conservation SciencesUniversity of MontanaMissoulaUSA

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