9. …… versus high severity wildfires.versus high severity wildfires.
10. The fire-scar record from tree rings.The fire-scar record from tree rings.
Southwestern white pine and ponderosa pine, Mt.
Graham, Arizona
ponderosa pine, El Malpais National Monument,
New Mexico
11. The fire-scar record from tree rings.The fire-scar record from tree rings.
Giant sequoia stump, Sequoia National Park, California
12. The fire-scar record from tree rings.The fire-scar record from tree rings.
Table Mountain pine snag, Brush Mountain, Virginia
13. The fire-scar record from tree rings.The fire-scar record from tree rings.
Catface on Table Mountain pine log, Reddish Knob, Virginia
14. The fire-scar record from tree rings.The fire-scar record from tree rings.
Fire scars on freshly-cut Table Mountain pine, Brush Mountain, Virginia
15. The fire-scar record from tree rings.The fire-scar record from tree rings.
Fire scars on ponderosa pine, El Malpais National Monument, New Mexico
16. The fire-scar record from tree rings.The fire-scar record from tree rings.
Fire scars on sugar
pine, Sequoia National
Park, California
17. The fire-scar record from tree rings.The fire-scar record from tree rings.
Fire scars on giant sequoia, Sequoia National Park, California
18. Seasonality of past fires from tree rings.Seasonality of past fires from tree rings.
Fire scar on
southwestern white
pine, Mt. Graham,
Arizona
19. Seasonality of past fires from tree rings.Seasonality of past fires from tree rings.
Detail of fire scar on ponderosa pine, El Malpais National Monument, New Mexico
20. Fire regimes:
• Fire frequency: how often
• Mean Fire Return Interval, Weibull Median Probability Interval
• Fire seasonality: when fires occur throughout the year
• Early season versus late season
• Fire severity: effects on forests
• Age structure, stand composition, stand structure
• Fire extent: spatial aspects
• Patchy fires versus landscape level fires
• Fire variability: changes in fire over time and space
• Climatic or human-driven?
21. Interpreting Fire History Charts
Years on x-axis
Period of Reliability: 1896 to 1944
Each line = 1 tree Sample IDs
Composite axis
Solid lines = recorder years
Each tic = fire scar
Dash lines = non-recorder years
Begin/end symbology
27. Stand age and composition:
• Core all species in your study area
• Core all trees in your study area
• Record tree and stand information
• Provides information on effects of
fire in forests = severity
• Were fires low-severity or
high-severity?
• Was this a mixed-severity fire
regime?
28. 0
5
10
15
20
25
30
35
40
45
50
1800 1825 1850 1875 1900 1925 1950 1975 2000
Establishment Year
DBH(cm)
Oak
Pine
Other Hardwoods
Brush Mountain Fire History
Period of Reliability: 1758–1934
All-scarred class:
MEI: 3 yrs; LEI: 1 yr; UEI: 8 yrs
10%-scarred class:
MEI: 8 yrs; LEI: 2 yrs; UEI: 19 yrs
90% DE fires, 10% MLA fires
Cohort establishment, with surviving
trees, then little fire for 20 years =
moderate severity fire in 1853
Cohort establishment, with surviving
trees, then little fire for 20 years =
moderate severity fire in 1853
Cohort establishment, with surviving
trees = moderate severity fire in 1926
Cohort establishment, with surviving
trees = moderate severity fire in 1926
29. 0
5
10
15
20
25
30
35
40
45
50
1800 1825 1850 1875 1900 1925 1950 1975 2000
Establishment Year
DBH(cm)
Pine
Oak
Other Hardwoods
Griffith Knob Fire History
Period of Reliability: 1810–1934
All-scarred class:
MEI: 2 yrs; LEI: 1 yr; UEI: 4 yrs
10%-scarred class:
MEI: 4 yrs; LEI: 1 yr; UEI: 12 yrs
72% DE fires, 28% MLA fires
Cohort establishment, with surviving
trees, after 1887-1890 complex of
fires, 1890 = moderate severity?
Cohort establishment, with surviving
trees, after 1887-1890 complex of
fires, 1890 = moderate severity?
Cohort establishment, with surviving
trees, after 1926 fire = moderate
severity fire
Cohort establishment, with surviving
trees, after 1926 fire = moderate
severity fire
31. Analyzing the Climate/Wildfire Relationship:
• Done using Superposed Epoch Analysis
• Originally developed to study the preconditioning controls of
natural events. Examples?
• Takes climate prior to, during, and after fire events, averages them
together.
• Where does climate information come from before climate records
were kept?
