1. 2010 Western Mensurationists Meeting Response of crown and canopy structure to stand density regime in western conifers Doug Maguire Giustina Professor of Forest Management Director, Center for Intensive Planted-forest Silviculture College of Forestry Oregon State University

2. Topics Crown and canopy structure of western conifers Crown structure Spacing effects on crown structure –Pringle Butte lodgepole-ponderosa pine mixed species spacing trials –Lookout Mountain ponderosa pine- grand fir mixed species spacing trials Other silvicultural influences Needs and directions

3. Topics Crown and canopy structure of western conifers Crown structure Spacing effects on crown structure –Pringle Butte lodgepole-ponderosa pine mixed species spacing trials –Lookout Mountain ponderosa pine- grand fir mixed species spacing trials Other silvicultural influences Needs and directions

4. Why crown structure ? Crown and canopy structure of western conifers Crown size drives growth and vigor

5. Why crown structure ? Crown and canopy structure of western conifers Crown size and its aggregate as canopy structure is key element in wildlife habitat (structural diversity) Crown area profile height Crown area

6. Why crown structure ? Crown and canopy structure of western conifers Crown size influences wood quality (branch size, crown wood core, microanatomy )? Josza and Middleton 1994 Branch diameter Crown wood core

7. Why crown structure ? Crown and canopy structure of western conifers Crowns ARE the tree-atmosphere interface (gas and heat exchange, light interception)

8. Why crown structure ? Crown and canopy structure of western conifers Crowns represent potentially utilizable biomass (biofuel feedstock) $

9. Why crown structure ? Crown and canopy structure of western conifers Crown structure influences fire behavior

10. Crown length? Resolution of crown structure for differing objectives What level of detail do we need for the purpose at hand? (Crown ratio)

11. Crown length and crown width? Resolution of crown structure for differing objectives

12. Crown length and crown width and biomass? Resolution of crown structure for differing objectives (leaf, branch,...)

13. First-order (primary) branches? Resolution of crown structure for differing objectives

14. Branches of all orders with detailed spatial information ? Resolution of crown structure for differing objectives

15. Spatial structure of all branches and leaves, or all structural modules ? Resolution of crown structure for differing objectives

17. As with any model, the objective or question dictates the appropriate level of detail For given objective and level of detail, does silviculture influence crown structure?

18. Topics Crown and canopy structure of western conifers Crown structure Spacing effects on crown structure –Pringle Butte lodgepole-ponderosa pine mixed species spacing trials –Lookout Mountain ponderosa pine- grand fir mixed species spacing trials Other silvicultural influences Needs and directions

19. Pringle Butte and Lookout Mountain mixed species spacing trials

20. 6.5 miles Lookout Mountain Pringle Butte Wickiup Reservoir Crane Prairie Reservoir La Pine

21. Pringle Butte ponderosa pine x lodgepole pine spacing trial Five initial spacings: 6, 9, 12, 15, 18 ft Three species mixes: pure PP pure LP 50:50 mix PP/LP Planted in 1967 PP/bitterbrush/snowbrush/sedge plant association Site index approximately 60 ft at 50 years Elevation ~ 4600 ft Annual precipitation ~24 inches

22. Pringle Butte ponderosa pine x lodgepole pine spacing trial 18 x 18 ft 6 x 6 ft

23. Lookout Mountain ponderosa pine x grand fir spacing trial Three initial spacings: 6, 12, 18 ft Three species mixes: pure PP pure GF 50:50 mix PP/GF Planted in 1974 Mixed conifer/snowbrush/chinkapin plant association Site index approximately 90 ft at 50 years Elevation ~ 5100 ft Annual precipitation ~39 inches

24. Lookout Mountain ponderosa pine x grand fir spacing trial 18 x 18 ft 6 x 6 ft

25. Mixed species spacing trials 6767 6868 6969 7070 7171 7272 7373 7474 7575 76767 7878 7979 8080 8181 8282 8383 8484 8585 8686 87878 8989 9090 9191 9292 9393 9494 9595 9696 9797 989890 0101 Measurement schedule Pringle Falls Lookout Mountain

26. Mixed species spacing trials Garber and Maguire 2004 Forest Science Standing volume ~proportional to initial spacing

27. Mixed species spacing trials Periodic annual increment starting to level out across spacings 15-20 yrs 20-25 yrs 25-34 yrs

28. Mixed species spacing trials Interaction of spacing and species composition on relative height development. LP PP GF

29. Vs. Mixed species spacing trials Implications for canopy structure, ladder fuels, spatial variation in crown bulk density.

30. Intensive crown sampling Sean Garber M.S. Thesis

31. Meticulous lab analysis of branches

32. Mixed species spacing trials Relative amount of foliage Shift in relative foliage and branch distribution among different initial spacings influence spatial pattern in crown bulk density

33. Pringle Butte ponderosa pine x lodgepole pine spacing trial

35. LP PP

36. Pringle Butte ponderosa pine x lodgepole pine spacing trial LP PP

37. Pringle Butte ponderosa pine x lodgepole pine spacing trial LP PP

38. Vs. Spacing effects on crown recession More rapid recession at closer spacings implies: -Loss of biomass - Accumulation of fuel

39. Ponderosa pine simulations based on initial conditions at Pringle & Lookout Three initial spacings grown out 100 years: 6-ft 12-ft 18-ft Thinning at years 25, 50 and 75, and all grown out 100 years: Residual SDI (% of max): 55% 41% 27% TPH SDI DBH HT

40. Ponderosa pine simulations based on initial conditions at Pringle & Lookout Number of branches Branch necromass Branch diameter

41. Annual branch mortality for ponderosa pine under different initial spacings Spacing effects through: - Time to crown closure - Rate of height growth after closure

42. Annual branch mortality for ponderosa pine under different initial spacings Site quality effect through rate of height growth  rate of crown rise

43. Annual branch mortality for ponderosa pine under different thinning regimes Thinning effect through temporary arrest of crown rise

44. Branch suppression mortality Branches from tree mortality Boles from tree mortality Total cumulative necromass under different initial spacings (Mg/ha)

45. Branch suppression mortality Branches from tree mortality Boles from tree mortality Total cumulative necromass under different thinning regimes (Mg/ha)

46. Topics Crown and canopy structure of western conifers Crown structure Spacing effects on crown structure –Pringle Butte lodgepole-ponderosa pine mixed species spacing trials –Lookout Mountain ponderosa pine- grand fir mixed species spacing trials Other silvicultural influences Needs and directions

47. buds Interwhorl branches Few interwhorl branches surviving Douglas-fir crown development from bud set through suppression mortality

48. Branch measurements by tree climbing

49. Branch measurements by destructive sampling

50. Diameter and height of individual Douglas-fir branches

51. Annual segments of main stem Douglas-fir (Maguire et al. 1994) max branch size number of branches relative size of branches relative position of branches

52. Reasonable fit to average distribution of branches

53. Mean of 142 annual stem segments But how plastic is this distribution with respect to tree attributes affected by silvicultural treatments?

54. Simulate branch occurrence as inhomogeneous Poisson process Changing Poisson mean, λ Changing probability of bud set or branch initiation Poisson regression with log link function (generalized linear model) η = ln(λ) = β 0 + β 1 X 1 + β 2 X 2 +... + β k X k where λ = mean of Poisson distribution

55. Annual height growth Live crown length Long stem segment (rapid growth)

56. Response of interwhorl branches in Douglas-fir to thinning more non- nodal buds same number of nodal buds control thinned

57. Simulation of primary branching structure, stochastic or otherwise

58. Pinus contorta Tsgua heterophylla Pseudotsuga menziesii Pinus ponderosa Abies grandis Larix laricina

60. Highest in clonal tamarack Most variable in Douglas-fir (but largest sample size)

61. Topics Crown and canopy structure of western conifers Crown structure Spacing effects on crown structure –Pringle Butte lodgepole-ponderosa pine mixed species spacing trials –Lookout Mountain ponderosa pine- grand fir mixed species spacing trials Other silvicultural influences Needs and directions

62. Driving forces Needs and Directions Improved G&Y models with dynamic link to determinants of stand productivity Predicting response of forests to climate change Estimating net primary production and sustainable level of biomass as energy feedstock Designing fire resistant stands and landscapes

63. Specifics Needs and Directions Crown profiles to better characterize distribution of foliage and non-photosynthetic tissues, leaf area density, crown bulk density Age class dynamics and implications for photosynthetic efficiency Nutrient content with respect to sampling and requirements for optimal nutrition

64. Foliage sampling in CIPS fertilization trials

65. Thanks to Doug Mainwaring for assistance with many past and ongoing projects

66. Thank YOU for your kind attention !

68. Western hemlock (Tsuga heterophylla) less visible pattern in size and distribution

69. annual segments end in one large branch western hemlock

70. Clonal tamarack (Larix laricina) similar to Douglas-fir, although no distinct whorl

71. Lodgepole pine (Pinus contorta) distinct whorls, but this species can have two cycles in some years (polycyclic)

72. ponderosa pine (Pinus ponderosa) very consistent unicyclic whorl structure relative uniformity in branch size within a whorl

73. Grand fir (Abies grandis) structure generally similar to Douglas-fir, but whorl branches attached at almost exactly the same height (horizontal branch angles)

74. Simulate branch occurrence as inhomogeneous Poisson process Increasing Poisson mean, λ Increasing probability of bud or branch set

75. Does stand density regime influence the number of primary branches initiated along the stem? Does stand density regime influence the number of primary branches surviving along the stem?

76. Needle primordia within bud of Douglas- fir, set at end of growing season (branches formed from axillary buds, but bud primordia not initiated until spring)

77. Axillary bud primordia (initiated ~ April 1): Aborted Latent Vegetative Seed cone Pollen cone vegetative latent aborted pollen cone seed cone bud primordia Douglas-fir bud (Allen and Owen) : needle primordia bud primordia

78. Percentage of axillary bud primordia that develops into various bud types in Douglas-fir vegetative latent early aborted seed cone pollen cone early aborted latent vegetative buds 14.1 15.7 8.7 10.9 11.3 6.7 age 50 30 15 50 30 15 Allen and Owen

79. A - Extended bud of Douglas-fir B - Extended bud with scales and some needles removed Developing axillary bud

80. Does stand density regime influence the number of bud primordia initiated or surviving along the stem? Apparently not known (?)

81. Does stand density regime influence the number of primary branches initiated or surviving along the stem? Limited evidence does suggest that number of branches per length of stem does respond to growing conditions.

82. Response of precommercially thinned Douglas-fir relative to unthinned controls non-nodal buds nodal buds (Maguire 1983)

83. density of non-nodal branches Maguire 1983 Response of precommercially thinned Douglas-fir relative to unthinned controls

84. more non- nodal buds same number of nodal buds control thinned

86. Lookout Mountain

87. Kelsey

88. Anomalies

89. Landscape canopy complexity and continuity

91. Anomalies

92. Kapur in Malaysia (Dryobalanops spp. )

94. Bulk density

95. Potential for simulating the process by which are buds set in a select few leaf axils  Branch position by height and azimuth Particularly appealing for Pseudotsuga, Abies, Picea species that have interwhorl branches grading into whorl branches Pont (2001) Use of phyllotaxis to predict arrangement and size of branches in Pinus radiata.