This document discusses several principles of dendrochronology: - The principle of ecological amplitude describes the range of habitats a tree species can grow in, and trees at the limits may be more sensitive to environmental changes. - The principle of site selection states that dendrochronologists should consider limiting factors and ecological amplitude to identify trees most likely to provide information about a specific environmental signal. - The principles of cross-dating, aggregate tree growth, and replication are important for dendrochronology research to build robust tree-ring chronologies.

1. October 18
23 the ‘detrended’
ring-width
Sampling aggregate
The linearstrategies model of tree growth
index

2. THE PRINCIPLE OF
ECOLOGICAL AMPLITUDE
A tree species may grow and reproduce over a certain range
of habitats; that range is described as its ecological amplitude.
Trees that grow near the margins or limits of their ecological
amplitude are o en sensitive to changes in their environment.

3. h p://esp.cr.usgs.gov/data/atlas/li le/

4. Source: Phil Camill

5. Average temperatures are remarkably consistent at treeline locations around the world.
Source: Körner and Paulsen, Journal of Biogeography, 2004

6. THE LAW OF THE MINIMUM
Growth is controlled by the scarcest resource
(limiting factor), not the total amount of
resources available

7. THE PRINCIPLE OF
SITE SELECTION
Dendrochronologists should apply the principles of
limiting factors and ecological amplitude to determine
which trees are most likely to provide information about a
specific environmental signal.

8. ecotone a transitional area where one plant community changes
into another, usually caused by changes in the environment such
as changes in elevation or soil characteristics.

9. h p://esp.cr.usgs.gov/data/atlas/li le/

10. Source: Greg Brooks

11. Source: Phil Camill

12. h p://esp.cr.usgs.gov/data/atlas/li le/

13. Dr. Hal Fri s
University of Arizona

14. Source: Fritts et al., Ecology, 1965

15. where do we find old trees?

18. Trees can grow anywhere!

19. Intermountain bristlecone pine 4,844 years
Source: Tom Harlan

20. h p://esp.cr.usgs.gov/data/atlas/li le/

21. Methuselah Ridge
Source: Tom Harlan

22. Bristlecone comparison photos

23. Wind erosion on bristlecone tag
Source: Tom Harlan

24. Bristlecone vista
Alerce 3,622 years
Source: Tim Waters

25. distribution map of
FITZROYA CUPRESSOIDES

26. Giant sequoia 3,266 years
Source: Julie Jordan Sco

27. h p://esp.cr.usgs.gov/data/atlas/li le/

28. Source: Byron Hetrick

29. Bristlecone vista
Coast redwood 2,200 years
Source: hoppinjonn

30. h p://esp.cr.usgs.gov/data/atlas/li le/

31. Source: Brandi Korte

32. The Seward oak 330 yr?
Source: Ralph Sievert

33. White cedar 1452
Source: Danny Margoles

34. OLDLIST h p://www.rmtrr.org/oldlist.htm

35. Eastern OLDLIST h p://www.ldeo.columbia.edu/~adk/oldlisteast/

37. “ Size ma ers not. Look at me. ”
Judge me by my size, do you?
Hm? Mmmm.
Yoda

39. Crown shape
fla ened, ‘bonsai’ shape, sparse
and open, may be lopsided.

40. Branches
few but large

41. Trunk shape
columnar

42. youngest
IDEALIZED SILHOUETTES OF middle
PONDEROSA PINES
oldest
good sites poor sites
Source: Huckaby et al., 2003

43. Dr. Neil Pederson Lamont-Doherty Earth Observation

44. Pederson, N. 2010. External characteristics
of old trees in the Eastern Deciduous Forest.
Natural Areas Journal 30, 396:407.

45. SIX
CHARACTERISTICS OF OLD TREES
smooth bark
low stem taper
high stem sinuosity
crowns with few, thick, twisting limbs
low crown volume
low ratio of leaf area to trunk volume

46. Quercus alba <150 yr, with flaky bark
Source: Neil Pederson

47. Quercus alba >250 yr, with low ridging on the bark
Source: Neil Pederson

48. Liriodendron tulipifera ca. 80 yr
Source: Neil Pederson

49. Liriodendron tulipifera ca. 500 yr
Source: Neil Pederson

50. Quercus muehlenbergii ca. 399 yr, with a low stem taper
Source: A. Wiggs

51. Lirodendron tulipifera showing serpentine bole and characteristic crown architecture
Source: Neil Pederson

52. Quercus muehlenbergii ca. 348 yr, with only a few large branches in its crown.
Source: Neil Pederson

53. Source: Diane Main

54. L. tulipifera with broken crown (le ) and a celery top crown (right)
Source: Neil Pederson

55. Source: Imagin Extra

56. where do we find tree-ring data?

57. INTERNATIONAL
TREE-RINGDATABANK
h p://www.ncdc.noaa.gov/paleo/treering.html

61. Exercise!
Use Google Earth to review the global
distribution of tree-ring data.

62. THE PRINCIPLE OF
CROSS-DATING
THE PRINCIPLE OF
AGGREGATE TREE GROWTH
THE PRINCIPLE OF
REPLICATION
STANDARDIZATION
THE PRINCIPLE OF
ECOLOGICAL AMPLITUDE
THE PRINCIPLE OF
SITE SELECTION

63. GEOG8280
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