1. Introduction to Dendrochronology and San Juan Fire Histories

2. Dendrochronology Dendron = Tree Chronos = Time Logos = Study of Dendron = Tree Chronos = Time Logos = Study of

3. Building a master chronology

4. Principles of Dendrochronology Uniformity Limiting Factors Sensitivity Ecological Amplitude Site Selection Crossdating Uniformity Limiting Factors Sensitivity Ecological Amplitude Site Selection Crossdating

5. Principle of Uniformity “The present is the key to the past.” ~James Hutton, 1785 ~James Hutton, 1785 “The past is the key to the future.” ~Dendro quote ~Dendro quote “The present is the key to the past.” ~James Hutton, 1785 ~James Hutton, 1785 “The past is the key to the future.” ~Dendro quote ~Dendro quote 1726-1797 James Hutton 1726-1797

6. Principle of Limiting Factors

7. Principle of Ecological Amplitude

8. Principle of Site Selection

9. Principle of Crossdating

10. 1899 1902 1904 1896 1893 1894 1894

13. San Juan Fire Histories

14. Recorder Trees

19. Jackson Mtn JAK5 JAK3 JAK1 JAK2 JAK1 JAK2 JAK4

22. Archuleta Mesa

23. F IRE H ISTORY P LOT

25. A Brief History…. Aristotle 350 BC Aristotle 350 BC da Vinci 1500 da Vinci 1500 Duhamel & Buffan 1737 Duhamel & Buffan 1737 Alexander Twining 1827 Alexander Twining 1827 Charles Babbage 1838 Charles Babbage 1838 Theodor Hartig 1855 Theodor Hartig 1855 Jacob Keuchler 1859 Jacob Keuchler 1859

26. Principle of Aggregate Tree Growth R t = Ring Growth G t = Age related growth curve C t = Climate related growth variation & trend D 1t = Endogenous disturbance pulse D 2t = Exogenous disturbance pulse E t = Random variation R t = Ring Growth G t = Age related growth curve C t = Climate related growth variation & trend D 1t = Endogenous disturbance pulse D 2t = Exogenous disturbance pulse E t = Random variation

27. Principle of Replication

28. Fire scar formation

30. Piedra Area

31. Sheep Creek

32. Fire History Locations

33. All Fires SitePeriodMFIRange Archuleta Mesa Dry Ponderosa Pine 1650 – 1900102 – 24 Turkey Springs Ponderosa Pine 1700 – 188061 – 18 Bear Park Warm-Dry Mixed Conifer 1685 – 188081 – 31 Jackson Mtn Cool-Moist Mixed Conifer 1685 – 1873102 – 25 Corral Mtn Cold-Wet Mixed Conifer 1685 – 1851183 – 45

34. 25% Scarred SitePeriodMFIRange Archuleta Mesa Dry Ponderosa Pine 1650 – 1900177 – 40 Turkey Springs Ponderosa Pine 1700 – 18801810 – 33 Bear Park Warm-Dry Mixed Conifer 1685 – 1880229 – 71 Jackson Mtn Cool-Moist Mixed Conifer 1685 – 18732110 – 65 Corral Mtn Cold-Wet Mixed Conifer 1685 – 18514224 – 65