Training and Pruning Basics Objectives and Tools.

Training and Training and Pruning BasicsPruning Basics

Objectives and Tools

Strong Tree Framework

Balanced Renewal

Facilitate Management

Harvest Sunlight Efficiently

Maintain Productivity

What happens if you do not What happens if you do not prune?prune?

Faster growthEarlier fruiting

Less light penetration

Poor spray coverage

More difficult to manage

Objectives of trainingObjectives of trainingA. Establish a strong tree frameworkB. Facilitate management of tree and

cropC. Harvest sunlight efficientlyD. Maintain productivity◦ by renewing fruiting wood

Balanced Renewal

A. Establish a Strong Tree A. Establish a Strong Tree FrameworkFramework

Upright vertical trunk

Well distributed scaffolds

Wide crotch angles

Structural Wood

Establish a Strong Tree FrameworkEstablish a Strong Tree Framework

Vertical trunk

Well Distributed Scaffolds

Establish a Strong Tree FrameworkEstablish a Strong Tree Framework

Wide branch angles are stronger

Narrow angles are weak and increase shading inside canopy

A Strong Tree Framework: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

B. Facilitate Management of B. Facilitate Management of the Tree and Cropthe Tree and Crop

Height of primary scaffolds

Distribute scaffolds wellTree uniformityTree size

Facilitate Management:Facilitate Management:1. Height of Primary Scaffolds1. Height of Primary Scaffolds

Access to tree base ◦ Irrigation, herbicides,

fertilizers

Allow air movement to minimize disease pressure

Facilitate Management:Facilitate Management: 2. Distribute Scaffolds Well2. Distribute Scaffolds Well

Easy entry to tree

Thinning, pruning, harvesting

Good pesticide coverage

Facilitate Management:Facilitate Management: 3. Tree Uniformity3. Tree Uniformity

Easier to train employees

Mechanization possible

Facilitate Management:Facilitate Management: 4. Tree Size4. Tree Size

Small trees are easier to work

No ladders neededEasy to reach all parts of treeBetter spray penetration

Facilitate Management of the Facilitate Management of the Tree and CropTree and Crop

Optimize height of primary scaffolds◦Allow space at tree base

Distribute scaffolds well◦Do not over crowd scaffolds

Tree uniformityLimit tree size with summer and winter pruning

C. Harvest Sunlight EfficientlyC. Harvest Sunlight Efficiently

Maximize surface area of orchard covered by canopy

Limit canopy depth

Harvest Sunlight Efficiently:Harvest Sunlight Efficiently: 1. Maximize surface area of 1. Maximize surface area of orchard covered by canopyorchard covered by canopy

Most rapid in high density plantings

Harvest Sunlight Efficiently:Harvest Sunlight Efficiently: 2. Limit Canopy Depth2. Limit Canopy Depth

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Canopy Depth (feet)

50%

30%

Light Intensity Decreases Within the Tree Canopy

Harvest Sunlight Efficiently:Harvest Sunlight Efficiently: 2. Limit Canopy Depth2. Limit Canopy Depth

Photosynthesis Decreases at Lower Light Levels

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% Full Sunlight

Harvest Sunlight Harvest Harvest Sunlight Harvest Efficiently:Efficiently:

Poor fruit color Poor fruit distribution

◦Less fruit bud developmentPoor fruit sizePoor fruit flavor

Poor Light Intensity Leads toPoor Light Intensity Leads to

Harvest Sunlight Efficiently:Harvest Sunlight Efficiently: Poor Light Intensity Leads to poor ColorPoor Light Intensity Leads to poor Color

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% Full Sunlight

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

Harvest Sunlight Efficiently:Harvest Sunlight Efficiently: Light Intensity Affects Light Intensity Affects Fruit Color and SizeFruit Color and Size

Harvest Sunlight Efficiently:Harvest Sunlight Efficiently:

Light Intensity and Fruit SizeLight Intensity and Fruit Size

% Light Penetration Fruit size (grams)

Harvest Sunlight Efficiently:Harvest Sunlight Efficiently: Light Intensity and Fruit DistributionLight Intensity and Fruit Distribution

% Light Penetration % Fruit Distribution

Harvest Sunlight Efficiently:Harvest Sunlight Efficiently:

Light Intensity and Fruit FlavorLight Intensity and Fruit Flavor

% Light Penetration % Soluble Solids

Harvest Sunlight EfficientlyHarvest 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

D. Maintain ProductivityD. Maintain ProductivitySustain maximum bearing area for maximal Sustain maximum bearing area for maximal

timetime

Balanced Renewal

D. Maintain ProductivityD. Maintain Productivity

Maintain light distribution in canopy

Remove unproductive woodMaintain good vegetative/fruit

balance

Maintain Productivity:Maintain Productivity: Maintain light distribution in canopyMaintain 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

Maintain Productivity:Maintain Productivity: Remove Unproductive WoodRemove Unproductive Wood

Fruiting wood which hangs down

Fruiting wood which is shadedWater sprouts and root suckersDiseased or damaged woodWeak or thin wood

Maintain Maintain Productivity:Productivity:

Remove Remove Unproductive Unproductive

WoodWood

◦Remove weak or thin wood

Maintain Maintain Productivity:Productivity:

Remove Remove Unproductive Unproductive

WoodWood

◦Remove weak or thin wood

Maintain Productivity:Maintain Productivity: Maintain good Maintain good

vegetative:fruit balancevegetative:fruit balance

◦Thin out excessively vigorous vegetative growth during summer◦Allows light into center of tree

Maintain Productivity:Maintain Productivity: Maintain good vegetative/fruit balanceMaintain good vegetative/fruit balance

Remove excessive fruiting woodIn peaches - remove 40-60% of new fruiting wood each year

Conclusions:Conclusions:How should you train your trees?How should you train your trees?Many approaches workOpen center is most common for peachesCentral leader is most common for pome

fruitFind a program that works and stick to it

Conclusions:Conclusions:How should you train your trees?How should you train your trees?Keep in mind the four objectives

Establish a strong tree frameworkFacilitate management of tree and

cropHarvest sunlight efficientlyMaintain productivity by balanced

renewal

Tools used in Tree TrainingTools used in Tree Training

Manipulation of apical Manipulation of apical dominancedominance

Controlled by the plant hormone auxin

Produced by actively growing shootsMoves down the branch with gravity

Effects of auxinEffects of auxin

Inhibits lateral bud break

Inhibits lateral shoot growth

Affects branch angle

PruningPruningRemove the Source of AuxinRemove the Source of Auxin

Heading CutHeading CutRemove part of the branch

Stimulate bud break near cut

Stimulate localized branching

PruningPruningRemove the Source of AuxinRemove the Source of Auxin

Thinning cutThinning cut

Remove branch at point of origin

Least invigorating cut

Promote light penetration into canopy

Maintenance pruning

Bend Branch Towards HorizontalBend Branch Towards Horizontal

Decreases amount of auxin moving from tip

Increase lateral branchingDecrease terminal growth

Bend to a 45 to 60 degree angle

Bend Branch Towards Bend Branch Towards HorizontalHorizontal

Decreases amount of auxin moving from tip

Increase lateral branchingBuds at highest point breakDecrease terminal growth

Bend below the horizontal

Timing of pruningTiming 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

Pruning Response Varies with Pruning Response Varies with TreeTree

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