1. September 18
How does weather affect tree growth?
Source: Paul Schulte

2. Red mangrove
Rhizophora mangle

3. Red mangrove
Rhizophora mangle

4. Red mangrove
Rhizophora mangle
Photograph: Kevin Hutchinson

5. Trees without rings
(approximate)

6. Bur oak
Quercus macrocarpa

7. GEOG5839
ARE TREE RINGS ANNUAL?

8. The “pinning” method Source: Keith Weston

9. Band dendrometer

10. Band dendrometer measurements on a white pine near Cloquet MN
Source: Alm and Brown, Minnesota Forestry Notes, 1964

11. Atomic bomb test in Almogordo, New Mexico, July 16, 1945.

12. Y ?
HHow do we know
W
temperate or boreal trees are
ANNUAL?

15. Phenology is the study of the timing of recurring
biological events, their relationship to biotic and
abiotic forces, and the inter-relations among phases
of the same or different species.

16. Bur oak (Quercus macrocarpa) is a common tree along rivers in Minnesota and the upper Midwest.
Select trees of this species can live for up to 450 years.

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

18. Dormancy
Fruit drop Bud break
Flowers visible Leaf out

19. DORMANCY
The buds of most temperature trees are protected by a
covering of scales during the dormant period.
Source: Steve Ryan

20. BUD BREAK
A leaf bud is considered "breaking" once a green leaf tip is
visible at the end of the bud.

21. LEAF OUT
A leaf is considered "unfolded" once its stalk or base is
visible outside of the bud.

22. FLOWERS VISIBLE
For bur oak, the male flowers hang loosely from the branch
and are called catkins.

23. FRUIT DROP
‘Fruit drop’ occurs when mature acorns are ripened
and have dropped from the tree.

24. Every species has its own phenological ‘calendar’
leaf out
flowers visible
fruit drop
bud break
dormancy dormancy
Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec Jan Feb

26. “ Cambial activity is not continuous in space or in time.
Kozlowski and Pallardy
”
Physiology of Woody Plants

27. GEOG5839
WEATHER, CLIMATE & TREES

28. temperature water day length

29. HOW DOES TEMPERATURE AFFECT TREE GROWTH?
Source: spaka acks

30. Source: Marchand, P. J. 1996. Life in the Cold: An
Introduction to Winter Ecology, 3rd ed. University
Press of New England. Hanover, NH. 304 pp.

33. carbon dioxide water oxygen water sugar
6CO2 + 12H20 ➔ 6O2 + 6H20 + C6H1206

34. TEMPERATURE
high growth
frozen water
low photosynthetic rate
low photosynthetic rate
higher evaporation
shorter growing season
low growth
cold hot

35. HOW DOES MOISTURE AFFECT TREE GROWTH?
Source: circulating

37. Source: Karen Rice

38. Stomata are microscopic pore on the epidermis (surface)
of land plants. Stomata act as gateways that allow plants
to exchange CO2 and O2 with the atmosphere.

39. PINE NEEDLE
leaf stomata

40. CO2
CO2
H2O H2O
LEAF CROSS-SECTION
abundant water

42. CO2 CO2 CO2
CO2 CO2 CO2
CO2 CO2
H2O H2O
H2O H2O
H2O
LEAF CROSS-SECTION
water shortage

43. WATER
high growth
reduced cell division
flooding
reduced cell expansion
anoxic conditions
C02 starvation
low growth
dry wet

44. HOW DOES DAY LENGTH AFFECT TREE GROWTH?
Source: Chris Nixon

45. DAY LENGTH
high growth
flowering
dormancy
germination
low growth
short long

46. total growth rate
growth rate due to temperature
G(t) = gE(t) • min[gT, gW] growth rate
growth rate
due to soil water
due to radiation
A er Evans et al., Journal of Geophysical Research, 2006

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

49. Source: Neil Pederson

50. GEOG5839
ECOLOGICAL SIGNALS

51. Tree-ring display at elementary school
Photograph:Tom Swetnam

52. Dr. Hal Fri s
University of Arizona

56. Fri s, Tree Rings and Climate, 1976

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

58. High
Low
Forest interior Semiarid forest border
DECREASING EFFECTIVE PRECIPITATION
INCREASING VARIABILITY IN ANNUAL PRECIPITATION
MORE DAYS WHERE MOISTURE IS LIMITING TO PROCESSES IN TREE
c.f. Fri s, 1976

59. High
Av
era
ge
rin
g-w
Ar idt
bo h
ria
ld
om
ina
nc
e
Low
Forest interior Semiarid forest border
DECREASING EFFECTIVE PRECIPITATION
INCREASING VARIABILITY IN ANNUAL PRECIPITATION
MORE DAYS WHERE MOISTURE IS LIMITING TO PROCESSES IN TREE
c.f. Fri s, 1976

60. High
S
NG
RI
N T
Low B SE
PERCENT A
Forest interior Semiarid forest border
DECREASING EFFECTIVE PRECIPITATION
INCREASING VARIABILITY IN ANNUAL PRECIPITATION
MORE DAYS WHERE MOISTURE IS LIMITING TO PROCESSES IN TREE
c.f. Fri s, 1976

61. High
E S
R E
T
N
EE
TW
BE
N
T IO
LA
R E
O R
Low C
Forest interior Semiarid forest border
DECREASING EFFECTIVE PRECIPITATION
INCREASING VARIABILITY IN ANNUAL PRECIPITATION
MORE DAYS WHERE MOISTURE IS LIMITING TO PROCESSES IN TREE
c.f. Fri s, 1976

62. High
E S
R E
T
N
EE
TW
BE
N
T IO
LA
R E
O R
Low C
Forest interior Semiarid forest border
DECREASING EFFECTIVE PRECIPITATION
INCREASING VARIABILITY IN ANNUAL PRECIPITATION
MORE DAYS WHERE MOISTURE IS LIMITING TO PROCESSES IN TREE
c.f. Fri s, 1976

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

64. “ Thus the physiological processes, such as photosynthesis,
respiration, assimilation, and cambial activity, are largely a
function of favorable or unfavorable climatic regimes, and
”
hence the trees exhibit a high amount of similar variation
in relative year-to-year fluctuations of their ring widths.
Fri s et al., 1965
Ecology

65. Source: United States Geological Survey

66. A species may grow and reproduce over a
certain range of habitats; that range is
described as its ecological amplitude.

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

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

69. THE PRINCIPLE OF
ECOLOGICAL AMPLITUDE
Trees that grow near the margins or limits of their ecological amplitude
are o en more sensitive to changes in their environment.

70. GEOG8280
XT C L AS S
NE