Crown-Condition Classification Tutorial

1. Crown-Condition Classification Tutorial (Revised January 2008)

3. Why Crowns? • To assess tree vigor and growth potential • Early warning sign of tree health deterioration • Crowns form the structural architecture of forests • Crowns influence understory flora and fauna • To assess individuals, ecosystems, states, regions

4. Crown Variables • Uncompacted Live Crown Ratio • Crown Position • Crown Light Exposure • Crown Density • Crown Dieback • Foliage Transparency • Sapling Vigor Class

5. Size Classes of Trees • Seedlings • <1.0-inch DBH/DRC • Saplings • 1 inch to 4.9 inches DBH/DRC • Trees • 5 inches + DBH/DRC

6. Crown Variables • Both Saplings and Trees • Uncompacted Live Crown Ratio • Crown Position • Crown Light Exposure • Trees Only • Crown Density • Crown Dieback • Foliage Transparency • Saplings Only • Crown Vigor Class

7. FIA Plot Configuration Macroplot-trees Subplot-trees Microplot-saplings

8. Definitions • Live branch Woody lateral growth supporting foliage and larger than 1 inch at the base just above the swelling where it joins the main stem.

9. Definitions • Twig Woody lateral growth with secondary branching and less than 1 inch in diameter at the point of attachment to a branch or crown stem.

10. Definitions • Sprig Woody or non-woody lateral growth without secondary branching and less than 1 inch.

11. Definitions • Snag branch Dead upper crown branches without fine twigs.

12. Definitions • Epicormic branches Woody or non-woody lateral growths, usually on the bole or crown stem and initiated by sudden exposure or loss of crown stem.

13. Definitions • Crown Outline Outline Exclude abnormally long branches

14. Definitions Crown Top • Crown Top

15. Definitions • Obvious Live Crown • Obvious Live Crown Base Obvious Live Crown Crown Base

16. Crown Base Definitions • Live Crown Base, Saplings

17. > 5 feet Definitions Point 1 • 5-ft Rule Point 2

18. Definitions • 5-ft Rule Point 1 < 5 ft Point 2

19. Viewing the Crown Quality Crown Measurements Require… • A calibrated eye • A positive attitude • Good weather and daylight • 2 certified crown raters working as a crew

20. Get Two Separate Views Of Every Crown!

21. 90o Viewing the Crown ½ to 1 tree length away View from grade level or upslope

22. Viewing the Crown • Separate the subject from other trees • Rate the whole crown, not just the easiest part to see

23. Viewing the Crown DON’T stand under the tree to make your ratings. DON’T stand at 180o from your partner.

24. Field Aid • Useful for…Live Crown RatioCrown DensityFoliage Transparency

25. Crown Variables • Both Saplings and Trees • Uncompacted Live Crown Ratio • Crown Position • Crown Light Exposure • Trees Only • Crown Density • Crown Dieback • Foliage Transparency • Saplings Only • Crown Vigor Class

26. X X Y Y ULCR = X/Y(100) Uncompacted Live Crown Ratio

27. Uncompacted Live Crown Ratio • Determine the LIVE TOP of the tree (dieback & dead branches excluded) • Establish the OBVIOUS LIVE CROWN BASE • Determine the ACTUAL LENGTH of the tree (same as defined in the Phase 2 field guide) • Express the length of the Obvious Live Crown as a PERCENTAGE of the Actual Length • Agree on best answer with your partner or average and record to the nearest percent

28. Uncompacted Live Crown Ratio For trees: The Obvious Live Crown includes foliage and branches down to the lowest foliage of the lowest 1-inch branch.

29. Uncompacted Live Crown Ratio For trees: The 5-foot, 1-inch rule <5 feet; include New Live Crown Base >5 feet; exclude >1 inch

30. ? ? ? ? >5 feet, >1 inch ULCR = 50 - 75%? Uncompacted Live Crown Ratio

31. 35% 50% 75% Include leafed twigs Exclude sprigs Uncompacted Live Crown Ratio For saplings: The Obvious Live Crown includes twigs, but not sprigs.

32. Uncompacted Live Crown Ratio X X/Y(100) Y Obvious Live Crown (X) excludes dieback. Actual Length (Y) includes dieback.

33. Uncompacted Live Crown Ratio Epicormic branches: If tree or sapling crown contains only epicormics, ULCR = 00

34. Crown Position • The relative position of each tree in relation to the main overstory canopy Four Codes: • Superstory • Overstory • Understory • Open Grown

35. Overstory Canopy Zone Average Live Crown Lengths of overstory trees

36. 1 2 2 midpoint 2 2 2 3 3 Crown Position

37. Crown Position Open Canopy: All saplings and trees coded 4 4 4 4 4

38. Crown Position <50% crown cover, > 1 acre in size Scattered All coded 4 Clumped

39. Crown Position • 2 Conditions (> 1 acre in size) • >50% crown cover • 1=Superstory (Never for saplings) • 2=Overstory • 3=Understory • <50% crown cover • 4=Open grown (all saplings/trees)

40. Crown Light Exposure The number of sides of a crown (including the top) that receive sunlight when the sun is directly overhead.

41. Crown Light Exposure

42. Crown Light Exposure In this case, the code for exposure would be 2

43. ULCR = 25% Code as 1 Crown Light Exposure

44. 3 1 2 0 4 5 Crown Light Exposure

45. Crown Variables • Both Saplings and Trees • Uncompacted Live Crown Ratio • Crown Position • Crown Light Exposure • Trees Only • Crown Density • Crown Dieback • Foliage Transparency • Saplings Only • Crown Vigor Class

46. Codes for 5-percent Classes • Crown density, crown dieback and foliage transparency… • 00 No Crown • 05 1-5% • 10 6-10% • 15 11-15% • … … • 99 96-100%

47. Crown Density • The amount of crown branches, foliage, and reproductive structures that block light visibility through the crown

48. Crown Density

49. Crown Density

50. plywood Density: 100% Crown Density