1. Trees and how they grow

2. Three main processes Respiration Transpiration Photosynthesis
Breathing & using energy
Drinking water
Making their own food

3. Respiration

4. Tree Structure

6. The trunk

8. Phloem zone

10. Longitudinal view of Vascular Cambium
Xylem tubes
Vascular rays

11. A Ray initiating at the Cambium/ Phloem interface and extending inwards

12. Annual Rings

13. Porous wood

14. Aporous wood
- note the denser appearance and the larger vessels

15. Growth Ring structure with xylem vessels

17. Archie the Bobcat operator

18. Doug the arborist

19. Archie removes his old girlfirend’s initials from the trunk of a tree with his Bobcat

20. What the #*^% do you think you are doing?

21. Doug talks CODIT – Archie learns

22. Compartmentalisation of Decay in Trees
CODIT

23. Figure 17
In a sense, a tree is a multiple perennial plant. Every growth ring can be thought of as an individual tree. Every new "tree" envelopes all the older trees. (fig.17)
                                    

24. When a tree is wounded, the outer tissues are removed.
Fungal spores float in the atmosphere and land on the wound colonising the exposed tissue

25.                                       
Fungal strands dissolve woody tissue and grow into the wood, starting the process of decay.
The tree responds with the development of several WALLS

26. Fungal attack of cells through cell walls where the contents of the cell are consumed by the fungi

27. Wall 1
Tyloses in the xylem vessels expand and block the vessels resisting vertical spread of decay

28. Xylem vessels
Tyloses

29. Wall 2 - The growth rings
The rings resist the inward spread of fungus. The deeper into the wood the fungus goes, the denser the wood, the more lignified the cells and the more resistant to the fungus the wood becomes

30. Wall 3 – The Rays
The Rays contain high levels of starch. These react with Oxygen to form Phenolic Acids. The acids are highly toxic to fungus and the fungus finds it difficult to spread in a radial direction.

31.                                         
Another close look at Walls 2 and 3 gives the impression of subdivided three dimensional wheels.(fig.20)

32. There is great variation in the dimension of Walls 3
Rays
Annual Rings
There is great variation in the dimension of Walls 3

33. The formation of Wall 4
The cells in the Vascular Cambium differentiate and do not produce new xylem and phloem cells.
At the edges of the wound new wood forms called Callus tissue

34. Wall 4
Callus tissue is a new layer of cells that grows over the damaged section in a 3d pattern.
At the point where the wound occurred a physical and chemical barrier is formed –
Wall 4

35. Wall 3
Wall 4
Wall 2
Wall 1

36. What it looks like… A wound with advanced fungal activity.
The fruiting body present shows extensive decay

37. Progressive wall 4 collapses and extensions of decay

38. Callus tissue closing over the wound
Wall 4 formed at the Vascular Cambium just after wounding, with only slight internal decay
An old wound

39. A completely compartmentalised wound – the callus tissue has met and joined.

40. A serious cavity in a Newcastle park
A serious cavity in a Newcastle park. A grown man can easily stand in this cavity

41. Home Sweet Home
Cavities provide habitat

44. Phytophthora in fruit trees

45. Tree Injection
A last resort for treating insect pests on leaves and some diseases in trees

46. t/R  0.3
If the ratio of the thickness (t) over the Radius (R) is less than 0.3 then the tree is considered unsafe
K. Mattheck 1999 t R

47.  The tree is unsafe as the ratio is less than 0.3
t = 200 mm
R = 700 mm
t/R = 200/700
= 0.286
 The tree is unsafe as the ratio is less than 0.3
An example t R

48. Some Facts… Painting wounds does not prevent decay in most situations
Water does not cause decay
Climbing using climbing spikes can lead to decay and should only be used for removal of trees
Any injury to the tree will lead to the process of compartmentalisation
Installing cables and rods can cause decay
Installing swings, bolts, nails, signs, wire etc can lead to decay.

49. A low t/R ratio here!!

51. Roots and mycorrhizae
The root, plus another organism can increase the roots’ effectiveness.
Ecto and Endo mycorrhizae
Vasicular arbiscular mycorrhizae (VAM)
Understanding the changes in the root zone cause a negative vortex which then gradually causes the death of the tree.