Supplement 1. Time series of annual fire extent in the U.S. northern Rockies.

<h2>File List</h2><blockquote> <p><a href="Northern_Rockies_fire_extent_ha.csv">Northern_Rockies_fire_extent_ha.csv</a></p> </blockquote><h2>Description</h2><blockquote> <p>Northern_Rockies_fire_extent_ha.csv contains a time series of annual fire extent in hectares from 12 national forests and 1 national park in Idaho and Montana west of the Continental Divide. In addition to total fire extent, it includes fire extent by vegetation type (environmental site potential, ESP). The column headings are self explanatory (year,total_fire_extent_ha,cold_forest_extent_ha,mesic forest_extent_ha,dry forest_extent_ha,woodland_extent_ha,mesic shrub_extent_ha,dry_shrub_extent_ha,grassland_extent_ha,other_extent_ha,sum_of_extent_by_ESP). total_fire_extent_ha is not exactly equal to sum_of_extent_by_ESP because the values by ESP were computed within the fire-atlas recording area only whereas a small percentage of total fire extent occurred outside the fire-atlas recording area.</p> <p>Checksum values for the columns are:</p> -- TABLE: Please see in attached file. -- <p>  </p> </blockquote

Appendix A. Taper equations used to reconstruct diameter at breast height of stumps.

Taper equations used to reconstruct diameter at breast height of stumps

Appendix B. Dendrogram results of hierarchical cluster analysis.

Dendrogram results of hierarchical cluster analysis

Appendix B. Model statistics comparing axial resin duct properties and ring width values between paired resistant and susceptible ponderosa pine trees.

Model statistics comparing axial resin duct properties and ring width values between paired resistant and susceptible ponderosa pine trees

Appendix A. Location and description of the sites used in each analysis.

Location and description of the sites used in each analysis

Appendix C. Model statistics comparing total duct area before and after one fire, before and after frequent fire, and with climate.

Model statistics comparing total duct area before and after one fire, before and after frequent fire, and with climate

Location of sites at which we compared fire and western spruce budworm outbreak histories.

<p>Shaded area shows the distribution of Douglas-fir and grand fir (the primary host species for western spruce budworm) according to Little (1971) <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114282#pone.0114282-Little1" target="_blank">[86]</a>.</p

Summary of superposed epoch analysis indicating the direction of Palmer Drought Severity anomalies for an 11-year window centered on outbreak initiation dates.

<p>Descending bars show the number of sites with a negative association with PDSI (i.e., droughty conditions), ascending bars show the number of sites with a positive association with PDSI (i.e., wetter conditions). Dark grey shading shows number of sites with statistically significant (at the 95% confidence interval) anomalies.</p

Western spruce budworm outbreak and fire reconstruction characteristics.

<p>Reconstructed outbreak record length (start date and end date), number of outbreaks reconstructed, average length of reconstructed outbreak periods, average length of reconstructed quiescent (non-outbreak) periods, reconstructed fire record length (start date and end date), number of fires reconstructed, average length return interval between fires (before 1890).</p><p>Western spruce budworm outbreak and fire reconstruction characteristics.</p

Tree-ring reconstructed chronologies of outbreaks of western spruce budworm (gray bars) and fire (vertical black lines).

<p>Dashed lines are the 40% threshold used to identify outbreak periods. The sites are arrayed from west (top) to east (bottom). See <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0114282#pone.0114282.s001" target="_blank">S1 Material</a> for detailed disturbance dates.</p