1. Dendrochronology of the Sunset Crater Tornado Paul Sheppard Elizabeth (Lizzie) May Sunset-Paricutín Crew

2. Sunset Crater

3. Erupted AD 1064 Dated dendrochronologically (Smiley 1958)

5. Other Processes? Climate: Drought, but long-term? Ecological: Defoliators, but non-fatal? Other geological: Landslide? Avalanche? Weather: High winds? Tornado?

6. Sunset Crater Tornado October 24, 1992 Touched down three times near Sunset Crater Toppled many trees Snapped branches on others Shook hundreds of trees

7. Dendro-tornado research Long-term wind effects on ring growth Forest compositional responses Nothing about tornado effects on ring growth per se

12. Sunset Crater Visitor Control Chronology (n = 8)

13. 1993 1. Ring-width release since 1993

14. 1993 2. Reaction wood since 1993 Some reaction-wood trees leaning Others appeared upright

15. 1993 3. Reaction latewood, 1993 Usually combined with wider rings Notice 2002.

17. 1993 4. A few suppressed rings after 1993

18. 5. Continuous suppression since 1993

19. 1993 6. Thin latewood, 1993

20. Tornado Conclusions Not every survivor shows a response Dominant response: ring-width release Most responses don’t look like AD 1064 One lengthy suppression a la AD 1064 AD 1064 probably not a tornado event

21. A Surprise Extended suppression, but not death

22. Decades-Long Suppression? Climate? Not conventionally Fire? No fire scar Leaning? Not leaning Defoliation? Not typically Some other pest? Sawfly?