Spaulding Gulch (site 11) - USSPG001 Additional Site Information Kathleen R. Maruoka, James K. Agee Dating Method: Crossdated Sample Storage Location: USDA Forest Service, Rocky Mountain Research Station Fire Sciences Laboratory 5775 West Highway 10 Missoula, MT 59808 Reference: Maruoka, K.R., 1994. Fire history of Pseudotsuga menziesii and Abies grandis stands in the Blue Mountains of Oregon and Washington. MS thesis. Seattle, WA: University of Washington. 73 p. Abstract: (from Maruoka thesis, 1994) Fifteen sites in the Blue Mountains of Oregon and Washington were sampled to survey fire frequency in stands ranging from Pseudotsuga menziesii associations to dry Abies grandis associations. Current stand structure at 80% of the sites consists of an overstory dominated by ponderosa pine, with Douglas-fir and grand fir the understory dominants. Pulses of establishment of Douglas-fir and grand fir occurred after the last recorded fire at 53% of the sites, while establishment pulses occurred amidst years of recorded fires at 47% of the sites. Patchiness in fire severity and fire spread, variable regeneration patterns, and sampling design may have influenced the interpretation of current stand stucture in the context of fire. Fire scar analyses reveal high variability in fire return intervals. Mean fire return intervals at each site range from 9.9 years to 49.0 years. Individual fire return intervals range from 2 years to 119 years, but may be highly subject to sampling limitations. Fire frequency variability could not be linked between sites to physical or geographic gradients. Comments: Fire-scarred sections were removed from up to four live trees at each site, generally 2 trees in one 100-m2 subplot and one tree in each of two 40-m2 subplots, except at site 1 (WID) where all three subplots were 40 m2. Fire-scarred sections were crossdated after this unpublished thesis was completed. One site (site 10) was used in the analysis presented in Heyerdahl (1997) and Heyerdahl et al. (2001) and submitted to the IMPD with that data set (USIRC001) as plot 9.4. Locations of trees and size of sampling areas were digitized from maps (roughly 1:100,000). Injuries are eroded scars only, those with much of the overlapping, curled woundwood rings destroyed by subsequent fires or rot. Heyerdahl, E.K. 1997. Spatial and temporal variation in historical fire regimes of the Blue Mountains, Oregon and Washington: the influence of climate. Ph.D. dissertation. Seattle: University of Washington. 224 p. Heyerdahl, E.K., L.B. Brubaker, and J.K. Agee. 2001. Spatial controls of historical fire regimes: multiscale example from the Interior West, USA. Ecology. 82:660-678. 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://frames.nbii.gov/fhaes/ for more information.