- -   AGRICULTURE CORE CURRICULUM  - -


(CLF7000)  Advanced Core Cluster:  PLANT AND SOIL SCIENCE

  (CLF7600)   Unit Title:  PRUNING

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  (CLF7606)   Topic:  PRUNING TO              Time      Taught in Year(s) 
                      ESTABLISH SCAFFOLDS     1 hour         3 AND 4        
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         Topic Objectives:  Upon completion of this lesson the student will 
         be able to:

         Learning Outcome #:

           (K-5)  -  Demonstrate how to prune to establish scaffold 
                     branches.

         Special Materials and Equipment: Pruning shears, sharpening stones.

         References: University of California,.  PRUNING DECIDUOUS FRUIT 
                       TREES.  Circ 444.

                     University of California,.  TRAINING AND PRUNING FRUIT 
                       TREES AROUND THE HOME.  Leaflet 2252.

         Evaluation: Quiz by instructor

TOPIC PRESENTATION:  PRUNING TO ESTABLISH SCAFFOLDS

A.  Fruit trees develop and produce differently in various environments.

    1.  They respond readily to cultural practices, especially pruning.

    2.  Correct pruning can make the difference between a strong fruitful
        tree and a weak less fruitful tree.

    3.  Tree training begins at planting time.

B.  At planting time imagine that your tree is ultimately going to grow into 
    the shape of a vase.

    1.  This mental image will help you direct and shape the growth of your 
        tree. 

    2.  In general the training principles are the same for all deciduous 
        fruit trees.

    3.  At planting time the tree is pruned to try to reach a balance 
        between the top and roots.

       a.  Digging of trees from the nursery and cutting off damaged roots 
           reduces the size of the root system.

       b.  The top of the tree is also reduced to obtain this balance.

    4.  Cut (head) the young tree so that it stands between 24 and 36 inches 
        above the ground (depending on desired crotch height).

    5.  Prune each lateral branch back to a single bud.

    6.  In May or June of the first growing season, select 3 well placed 
        shoots to form the main scaffolds of the tree.

        a.  Pinch back or remove the others.

        b.  The lowest branch should be at least 12 inches from ground 
            level.

    7.  At the first dormant pruning after planting select three primary 
        framework branches.

        a.  As the tree grows these selected branches will grow in diameter,
            but they will always remain the same distance from the ground.

        b.  Narrow-angled crotches formed by scaffolds emerging opposite 
            each other form very weak attachments.  One should be removed.

    8.  Here are some additional tips.

        a.  When selecting scaffolds, favor the north side;  the south side 
            will grow strong anyway, and try to select one scaffold to grow 
            into the prevailing wind.  (Question - Why will the south side 
            of the tree grow more vigorously?)

        b.  Keep the south side from getting too flat, (the tree will grow 
            toward the sun).

        c.  Keep north east scaffolds from getting too flat to avoid sunburn 
            damage.

        d.  Never allow 3 branches to arise from one point.

        e.  Head primary scaffolds approximately 30 to 40 inches from the 
            crotch 5 to 7 secondary scaffolds can be selected at shoulder 
            height, during or after the second growing season.

        f.  Always try to keep the tree symmetrical.

        g.  Leave the center open.


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          ACTIVITY:  
                      
          1.  Plant and prune young trees.

              a.  Instructor should demonstrate proper training and
                  pruning techniques.

              b.  Let students practice with close supervision.

          2.  On rainy days this can be done by bringing in branches
              pruned off larger trees.  These branches can represent 
              the young trees and can be done indoors.

          3.  Hold a critique at the end of each pruning session to
              clarify points and answer questions.
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7/25/90 sg

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