Churn Creek Protected Area - CACPA001
Harvey, Jill,E.; Smith,Dan,J.; Veblen,Thomas,T.

Dating method: crossdated

Sample storage location: Corresponding author personal storage

Reference: 
2017. Harvey, J., Smith, D., Veblen T.T. Mixed-severity fire history at a forest-grassland ecotone in west central British Columbia, Canada. Accepted by Ecological Applications. 

Abstract: 
This study examines spatially variable stand structure and fire-climate relationships at a low elevation forest-grassland ecotone in west central British Columbia, Canada. Fire history reconstructions were based on samples from 92 fire-scarred trees and stand demography from 27 plots collected over an area of about 7 km2. We documented historical chronologies of widespread fires and localized grassland fires between AD 1600 and 1900. Relationships between fire events, reconstructed values of the Palmer Drought Severity Index and annual precipitation were examined using superposed epoch and bivariate event analyses. Widespread fires occurred during warm, dry years and were preceded by multiple anomalously dry, warm years. Localized fires that affected only grassland-proximal forests were more frequent than widespread fires. These localized fires showed a lagged, positive relationship with wetter conditions. The landscape pattern of forest structure provided further evidence of complex fire activity with multiple plots shown to have experienced low, mixed and/or high-severity fires over the last four centuries. We concluded that this forest-grassland ecotone was characterized by fires of mixed-severity, dominated by frequent, low-severity fires punctuated by widespread fires of moderate to high severity. This landscape-level variability in fire-climate relationships and patterns in forest structure has important implications for fire and grassland management in west central British Columbia and similar environments elsewhere. Forest restoration techniques such as prescribed fire and thinning are oftentimes applied at the forest-grassland ecotone on the basis that historically high frequency, low severity fires defined the character of past fire activity. This study provides forest managers and policy makers important information on mixed severity fire activity at a low elevation forest-grassland ecotone, a crucial prerequisite for the effective management of these complex ecosystems.

NOAA/IMPD web landing page for this fire history site is available at:
https://ncdc.noaa.gov/paleo/study/21871

NOAA/IMPD DIF metadata record for this fire history site is available at:
https://www1.ncdc.noaa.gov/pub/data/metadata/published/paleo/dif/xml/noaa-fire-21871.xml

FHX filename: cacpa001.txt

IMPD code: CACPA001

Name of site: Churn Creek Protected Area

Site code: CCPA

Contributors: Harvey, Jill,E.; Smith, Dan, J.; Veblen,Thomas,T.

Latitude: 51.450000 (WGS84)

Longitude: 122.292000 (WGS84)

Mean elevation: 1050 (meters)

Country: Canada

State: British Columbia

Region: west central British Columbia

First year: 1436 AD

Last year: 2011 AD

Species name: Pseudotsuga menziesii [PSME]

Funding agency names and grant numbers: 
National Science and Engineering Research Council

Comments:
This site was sampled to reconstruct historical fire regimes in the Churn Creek Protect Area (CCPA).

Ring-boundary fire scars were assigned to the preceding calendar year.

Several metadata files are provided with the FHX file.   -999 in any file indicates no data.

Fire History Graphs: Fire History Graphs illustrate specific years when fires occurred and how many trees were scarred. They are available in both PDF and PNG formats. The graphs consist of 2 parts, both of which show the X axis (time line) at the bottom with the earliest year of information on the left and the latest on the right. The Fire Index Plot is the topmost plot, and shows two variables: sample depth (the number of recording trees in each year) as a blue line along the left Y axis, compared with the percent trees scarred shown as gray bars along the right Y axis. Below, the Fire Chronology Plot consists of horizontal lines representing injuries by year on individual sampled trees. Symbols are overlain that denote the years containing the dendrochronologically-dated fire scars or injuries. The sample ID of each tree is displayed to the right of each line. The Composite Axis below represents the composite information from all individual series. The symbols used to represent the fire scars or injuries, and the filters used to determine the composite information, are shown in the legend. These graphs were created using the Fire History Analysis and Exploration System (FHAES). See http://www.fhaes.org for more information.