Pruning. Harvey Holt Purdue University. First cut Notch below A Second cut Line A B Third cut Line C D. C to X Don t cut here!!

Transcription

1 Pruning First cut Notch below A Second cut Line A B Third cut Line C D C to X Don t cut here!! Harvey Holt Purdue University

2 Pruning Standards ANSI A300 (Part 1) 2001 Pruning

3 ANSI A-300 STANDARDS Intended as a guide for federal, state, municipal and private authorities in the drafting of maintenance specifications and should be adopted by them in whole or in part.

4 American Forests U.S. Forest Service American Nursery and Landscape Assoc. American Society of Landscape Architect Associated Landscape Contractors of America Professional Grounds Management Society Asplundh Tree Expert National Park Service Tree Care Indust. Asso. American Society of Consulting Arborists International Society of Arboriculture Society of Municipal Arborists Utility Arborist Assoc. Bartlett Tree Expert Co. Davey Tree Expert Co.

5 Consensus Public Review Shall mandatory requirement Should advisory recommendation

6 Why Prune Reduce risk Maintain or improve tree health or structure Improve aesthetics Satisfy specific need

7 Pruning Removal of plant parts

8 Prune According to Tree Growth Types - Genetic Excurrent Decurrent

9 Excurrent Sweetgum Tulip poplar Pines, cedars, fir, spruce Lateral buds grow first season Terminal bud outgrows laterals

10 Decurrent Oak Maple Elm Lateral buds grow in the second season Laterals outgrow terminal bud

11 Bud Growth Terminal Lateral

12 Terminal Bud - Auxin Hormone - Auxin Auxin controls growth of lateral buds below Terminal bud removal releases buds at or below the cut Resulting in multiple sprouts

13 Multiple Sprouts Weakly attached

14 Weak Attachment Branch formed from adventitious bud begins to add wood at the point of attachment

15 Branch bark ridge Branch wood Branch collar Stem wood

16 2001 International Society of Arboriculture

17 Branch Bark Ridge Raised area of bark at the branch junction that marks where the branch wood and trunk wood meet.

18 Tissue which forms at base of branch Branch Collar

19 Proper Pruning 1st cut 12 Prevents bark tearing

20 Proper Pruning 2nd cut 1st cut 12 3rd cut

21 Removing Codominant Leader The angle of the final cut should bisect the angle formed by the branch bark ridge and an imaginary line made perpendicular to the leader being removed.

22 Heading Cut used to Reduce Height of Tree leader imaginary line final cut branch bark ridge branch collar 2001 International Society of Arboriculture

23 Cut dead branch off outside live wood

24 Flush cut improper pruning

25 Decay entering tree as a result of flush cut

26 Wounds don t healthey seal through CODIT

27 Wound closure Fastest in spring when tree is rapidly growing Slowest in fall when growth has slowed down

28 Wound closure Branches over 6 will close very slowly and maybe never.

29 Don t Leave Stubs

30 Compartmentalization of Decay Wall 3 sideward Wall 4 Outside in Wall 2 inward Trees Wall1 above below CODIT

31 Tree Protection Wall 1- prevents decay spread up and down Wall 2 - prevents internal spread (annual rings) Wall 3 - prevents sideways spread Wall 4 - outer wall

32 How Much to Prune Not more than 1/4 of the tree s foliage should be removed per year Leave 1/2 foliage in bottom 2/3 of tree Keep tree s natural shape Well pruned tree won t look pruned

33 ANSI PRUNING SPECS - MATURE TREE PRUNING Hazard Reduction Pruning Maintenance Pruning Crown Cleaning Crown Thinning Crown Raising Crown Reduction Crown Restoration Vista Pruning

34 Pruning Types Clean Thin Raise Reduce

35 Crown cleaning shall consist of the selective removal of one or more of the following items: dead, dying, diseased, weak branches and water sprouts from a tree s crown. Crown Cleaning

36 Crown thinning shall consist of the selective removal of branches to increase light penetration, air movement, and reduce weight. Crown Thinning

37 Crown Raising Crown raising shall consist of the removal of the lower branches of a tree in order to provide clearance for sidewalks or streets

38 Crown Raising By Trucks Poor Tree Selection for the Location Crown Raising is necessary along city streets 15

39 Crown Reduction Crown reduction reduces the height and/or spread of a tree. Consideration should be given to the ability of a species to sustain this type of pruning. Pruning cuts back to a lateral

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41 Removing larger limb Cut limbs back to laterals at least 1/3 the size of the parent limb Remaining branch should be this size 2 6 parent limb with a lateral less than 1/3 its size

42 Vista Pruning Pruning for a specific view

43 Crown Restoration Rehabilitation from previous topping Takes several years of removing limbs to restore natural shape

44 How NOT to prune

45 Improper practices Shearing/Roundovers

46 Improper Practices Lion tailing

47 Improper Practice Lion-tailing Removes all interior branches

48 Improper Practices-Flush Cut Why? Removes branch collar Interferes with CODIT Cuts into trunk wood Leaves Larger wound

49 Improper Practice Wound Dressing

50 Improper practices Topping

51 More Topping shows multiple branches

52 What do you think the branch attachments look like?

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54 Specialty Pruning Young trees Central leader Scaffold branches selected Branches on lower trunk Restoration Vista

55 Young tree pruning goals Health Disease prevention Structure Provide a strong basic structure Remove undesirable growth Do not create problems from sunscald etc. Foliage distribution

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57 Limbs to remove Dead Dying Diseased Broken Defective

58 Maintain strong central leader On trees with excurrent habit

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61 Remove Codominant or Multiple leaders

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64 Co-dominant stems with included bark

65 Remove branches to develop good branch structure

66 Good branch structure u-shape

67 Included bark

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71 Maintain ½ of the foliage on the lower 2/3 of the limb

72 Young Tree Pruning Do not remove lower limbs they are needed to shade the trunk

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75 Provide Adequate Spacing For Scaffold Limbs 6 to 8 inches for small trees 18 inches for large trees

76 Too many branches poor structure

77 Too many branches poor structure

78 Too many branches poor structure causes branches to break off

79 Good branch structure

80 Maintain Radial Symmetry

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83 Select Branch Angles 45 to 90 degrees

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85 Maintain Crown shape of species

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87 Pruning Interval At planting 2 4 years 4 6 years

88 At Planting Broken or split limbs Dead, dying, diseased Structural problems Select single leader

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90 At 2 4 Years After Planting Repeat procedure done at planting + Develop strong scaffold Proper limb spacing (18 or 6 ) Remove interfering, crossing

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93 At 4 6 Years After Planting Same as 2 4 years after planting Remove lower limbs as needed

94 Need for Crown Raising

95 When To Prune When the saw is sharp Except when leaves are first developing Or dropping

96 Common Pruning Errors Removal of interior branches Removal of lower limbs Removal of central leader Waiting too long to start

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98 OTHER PRUNING TYPES Fruit Tree Fruit production Pollard Maintain size, formal Vista Maintain a view Espalier Restrict growth to a plane

99 Fruit Production

100 Pollarding

101 Pollard Procedures It is essential that the pollard head is retained, for it protects the trunk from rot.

102 Espalier

103 Utility Pruning Safe service Reliable service

104 Utility Pruning Done to prevent the loss of service and avoid damage to equipment Only qualified line clearance tree trimmers or trainees should be assigned

105 Utility Pruning - Urban Same pruning cut standards Minimum number of pruning cuts Remove branches at laterals not at pre-established clearing limit

106 Utility Crown Reduction Pruning Make the minimum number of cuts, consider natural shape Trees directly under wires should be removed or pruned Remove entire branches to parent limb or trunk to prevent regrowth

107 Rural Areas Climbing spurs may be used if necessary Mechanical pruning may be used Cuts should be close to trunk, avoid tearing bark

108 Emergency Service Restoration During a declared emergency deviation from proper pruning techniques is allowed After the emergency, corrective pruning should be done as necessary

109 Not appropriate utility pruning -

110 Directional Pruning

111 V-pruning

112 Side pruning

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