1. Training and Pruning Basics Objectives and Tools

2. Strong Tree Framework Balanced Renewal Facilitate Management Harvest Sunlight Efficiently Maintain Productivity

3. What happens if you do not prune? Faster growth Earlier fruiting Less light penetration Poor spray coverage More difficult to manage

4. Objectives of training A. Establish a strong tree framework B. Facilitate management of tree and crop C. Harvest sunlight efficiently D. Maintain productivity ◦ by renewing fruiting wood Balanced Renewal

5. A. Establish a Strong Tree Framework Upright vertical trunk Well distributed scaffolds Wide crotch angles Structural Wood

6. Establish a Strong Tree Framework Vertical trunk Well Distributed Scaffolds

7. Establish a Strong Tree Framework Wide branch angles are stronger Narrow angles are weak and increase shading inside canopy

8. A Strong Tree Framework: Major objective of the first three years Must last the lifetime of the tree Structural support for fruit crop Should not be crowded

9. B. Facilitate Management of the Tree and Crop Height of primary scaffolds Distribute scaffolds well Tree uniformity Tree size

10. Facilitate Management: 1. Height of Primary Scaffolds Access to tree base ◦Irrigation, herbicides, fertilizers Allow air movement to minimize disease pressure

11. Facilitate Management: 2. Distribute Scaffolds Well Easy entry to tree Thinning, pruning, harvesting Good pesticide coverage

12. Facilitate Management: 3. Tree Uniformity Easier to train employees Mechanization possible

13. Facilitate Management: 4. Tree Size Small trees are easier to work No ladders needed Easy to reach all parts of tree Better spray penetration

14. Facilitate Management of the Tree and Crop Optimize height of primary scaffolds ◦Allow space at tree base Distribute scaffolds well ◦Do not over crowd scaffolds Tree uniformity Limit tree size with summer and winter pruning

15. C. Harvest Sunlight Efficiently  Maximize surface area of orchard covered by canopy  Limit canopy depth

16. Harvest Sunlight Efficiently: 1. Maximize surface area of orchard covered by canopy M ost rapid in high density plantings

17. Harvest Sunlight Efficiently: 2. Limit Canopy Depth 50% 30% Light Intensity Decreases Within the Tree Canopy

18. Harvest Sunlight Efficiently: 2. Limit Canopy Depth Photosynthesis Decreases at Lower Light Levels

19. Harvest Sunlight Harvest Efficiently: Poor fruit color Poor fruit distribution ◦Less fruit bud development Poor fruit size Poor fruit flavor Poor Light Intensity Leads to

20. Harvest Sunlight Efficiently: Poor Light Intensity Leads to poor Color Harvest Sunlight Efficiently: Poor Light Intensity Leads to poor Color

21. Harvest Sunlight Efficiently: Harvest Sunlight Efficiently: Light Intensity Affects F ruit Color and Size

22. Harvest Sunlight Efficiently: Light Intensity Affects Fruit Color and Size

23. Harvest Sunlight Efficiently: Light Intensity and Fruit Size Harvest Sunlight Efficiently: Light Intensity and Fruit Size % Light PenetrationFruit size (grams)

24. Harvest Sunlight Efficiently: Light Intensity and Fruit Distribution % Light Penetration% Fruit Distribution

25. Harvest Sunlight Efficiently: Light Intensity and Fruit Flavor % Light Penetration % Soluble Solids

26. Harvest Sunlight Efficiently Maximize Orchard Floor Covered with Canopy Limit canopy depth to 1.0 m. Expose all parts of the canopy with at least 50% sunlight

27. D. Maintain Productivity Sustain maximum bearing area for maximal time Balanced Renewal

28. D. Maintain Productivity Maintain light distribution in canopy Remove unproductive wood Maintain good vegetative/fruit balance

29. Maintain Productivity: Maintain light distribution in canopy Only sun-exposed areas produce quality fruit Limit canopy depth to 1.0 m. Control tree size ◦Unless control tree size the fruit moves up every year ◦Lower part of tree will be shaded

30. Maintain Productivity: Remove Unproductive Wood Fruiting wood which hangs down Fruiting wood which is shaded Water sprouts and root suckers Diseased or damaged wood Weak or thin wood

31. Maintain Productivity: Remove Unproductive Wood ◦Remove weak or thin wood

32. Maintain Productivity: Remove Unproductive Wood ◦Remove weak or thin wood

33. Maintain Productivity: Maintain good vegetative:fruit balance Maintain Productivity: Maintain good vegetative:fruit balance ◦Thin out excessively vigorous vegetative growth during summer ◦Allows light into center of tree

34. Maintain Productivity: Maintain good vegetative/fruit balance Remove excessive fruiting wood In peaches - remove 40-60% of new fruiting wood each year

35. Conclusions: How should you train your trees? Many approaches work Open center is most common for peaches Central leader is most common for pome fruit Find a program that works and stick to it

36. Conclusions: How should you train your trees? Keep in mind the four objectives [ Establish a strong tree framework [ Facilitate management of tree and crop [ Harvest sunlight efficiently [ Maintain productivity by balanced renewal

37. Tools used in Tree Training Manipulation of apical dominance Manipulation of apical dominance  Controlled by the plant hormone auxin  Produced by actively growing shoots  Moves down the branch with gravity

38. Effects of auxin 4 Inhibits lateral bud break 4 Inhibits lateral shoot growth 4 Affects branch angle

39. Pruning Remove the Source of Auxin Heading Cut Heading Cut 4 Remove part of the branch 4 Stimulate bud break near cut 4 Stimulate localized branching

40. Pruning Remove the Source of Auxin Thinning cut Thinning cut 4 Remove branch at point of origin 4 Least invigorating cut 4 Promote light penetration into canopy 4 Maintenance pruning

41. Bend Branch Towards Horizontal Decreases amount of auxin moving from tip Increase lateral branching Decrease terminal growth Bend to a 45 to 60 degree angle

42. Bend Branch Towards Horizontal Decreases amount of auxin moving from tip Increase lateral branching Buds at highest point break Decrease terminal growth Bend below the horizontal

43. Timing of pruning Dormant pruning ◦Most common approach Summer pruning ◦Works well in combination with dormant pruning ◦Open up the tree to allow light into center

44. Pruning Response Varies with Tree Different varieties/crops grow differently ◦Spur types in apples Vigor level of the tree ◦Age of the tree ◦Rootstock ◦Fertility/irrigation/soil constraints Small fruited vs. large fruited crops