Training and Pruning Basics

Training and Pruning Basics Objectives and Tools

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

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

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

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

Vertical trunk Well Distributed Scaffolds Establish a Strong Tree Framework

Wide branch angles are stronger • Narrow angles are weak and increase shading inside canopy Establish 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 A Strong Tree Framework:

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

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

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

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

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

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 Facilitate Management of the Tree and Crop

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

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

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

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

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

Harvest Sunlight Efficiently:Poor Light Intensity Leads to poor Color

Harvest Sunlight Efficiently:Light Intensity Affects Fruit Color and Size

% Light Penetration Fruit size (grams) Harvest Sunlight Efficiently:Light Intensity and Fruit Size

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

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

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

Balanced Renewal D. Maintain ProductivitySustain maximum bearing area for maximal time

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

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 light distribution in canopy

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

Remove weak or thin wood Maintain Productivity:Remove Unproductive Wood

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

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

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 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 Conclusions:How should you train your trees?

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

Inhibits lateral bud break • Inhibits lateral shoot growth • Affects branch angle Effects of auxin

Heading Cut • Remove part of the branch • Stimulate bud break near cut • Stimulate localized branching PruningRemove the Source of Auxin

Thinning cut • Remove branch at point of origin • Least invigorating cut • Promote light penetration into canopy • Maintenance pruning PruningRemove the Source of Auxin

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

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

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

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 Pruning Response Varies with Tree

Training and Pruning Basics