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Pruning. Pruning is…. The term used for the selective removal or reduction of certain plant parts. Pruning ranges from removing selected parts or removal of huge limbs. Improper pruning can lead to unsightly plants. What to Prune….
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Pruning is… • The term used for the selective removal or reduction of certain plant parts. • Pruning ranges from removing selected parts or removal of huge limbs. • Improper pruning can lead to unsightly plants.
What to Prune… • 1. Make cuts that cause the least amount of damage to the plant. • 2. Begin pruning practices when the plant is young. • 3. In most cases, prune after the plant has flowered. • 4. Safely use sharp tools suitable for the job.
Reasons to prune • Develop a strong framework of branches that resist breakage and provide an attractive appearance • Restrict size of a plant • Repair damaged limbs • Improve flowering of trees and shrubs • Remove diseased or insect infested limbs, reducing the spread of pests. • Directing growth • Maintain desired cultivars
Opening the crown to allow light and wind to pass • Maintain safe conditions • Improve quality of fruit.
Branching Framework • Trees should have a single, strong leader. • Leader- a central branch that dominates over the other branches on the tree. • Sometimes co-leaders are formed and this causes a tree to become weak and unattractive. • Pruning should be started when a tree is young. • The best way to get rid of co-leaders is to identify the best and prune the others.
Subordination- cuts made that slow the growth of a branch. • Good to use in a small tree with multiple leaders.
Scaffold branches- grow laterally from the trunk. • Branches that develop a 45 to 90 degree attachment are structurally strong. This is considered to be a U-shaped crotch. A V-shaped crotch is undesirable and are usually weak. • Watersprouts- are soft, green shoots that typically grow vertically from existing branches. • Suckers- are soft, green shoots that develop from the base of the tree.
Removal of suckers is particularly important when a plant is a cultivar– which is a plant that is produced by grafting. Ex: red delicious apples and golden delicious apples, knock-out roses. • Grafting- Joining two different plants together to form a new, better plant. • Scion- Top growth of a graft • Rootstock- Root/bottom growth of the graft • Rootstock does not usually have desired qualities. Used for its root quality.
Diseased or Dead Wood • Broken or diseased wood should be removed as dead wood prevents the tree from healing. • They are also safety hazards.
Crossing branches • The rubbing of the two branches causes friction and leaves an open wound on the tree where insects and disease may enter. • Remove the less important of the two branches. • It is best to look for these when the tree is young.
Compartmentalization • Is the way that the trees heal themselves after wounded. Trees produce chemicals that inhibit decay caused by bacteria and fungi, these chemicals seal the wound.
Callus- a protective growth of tissue, over the wound. • Collar- swollen trunk tissue surrounding the base of the branch. • Branch bark ridge- a raised line of bark that forms on the upper side of the branch where the branch joins the trunk. • Never remove the collar or bark ridge when pruning since this is where the tree releases the chemicals to prevent decay.
Which pruning cut to use • Drop- crotch pruning- is a method that effectively shortens tree limbs and reduces the size of a tree. • It also helps direct the growth of young trees. • Only accepted pruning technique for reducing height of a tree. • Thinning cut- open up canopy to allow light. Does not reduce the size of a tree. Mature Trees • Heading cuts- made between nodes on stem to promote branching or to direct growth. Young trees
When to Prune… • Varies by the type of plant. • Most deciduous trees should be pruned late winter and early spring. • If it is a ornamental flowering tree or shrub prune after it has flowered for the spring.
Pruning Deciduous Shrubs • There are 3 types of pruning for deciduous shrubs: • Renewal pruning- is defined as the selective removal of older plant stems, new growth is encouraged, the plant size is maintained, and flowering is promoted. • Cut stems at ground level. • Choose stems carefully • Lilacs, Forsythias, and Viburnum respond well to this type of pruning.
Rejuvenation pruning- is a method of pruning deciduous shrubs that involves removing all stems to 4-6 inch stubs. • Late winter to early spring is the best time to do this type of pruning. • Spirea and Honeysuckle respond well to this.
Heading Back- involves the shortening of individual stems using heading cuts. • Using heading back removes dead or diseased wood and to restrict size. • Cuts are made back to the parent stem rather than to the ground.
Shearing- effectively reduces the total leaf surface a plant has to produce energy. As a result the plant is placed under stress. This is used to make geometric shapes.
Pruning Evergreens • Arborvitae- maintained easily by heading back limbs with hand- held pruners. Prune in spring. Avoid severe pruning that exposes dead zones. • Dead Zone- a region in the center of the plant that seldom produces new shoots. • Firs- annual pruning in early summer, to shorten the leader and lateral shoots, promotes dense growth. • Junipers- use heading back method in spring. Stay clear of the dead zone as the dead zone will not produce green foliage again.
Pines- Prune when they are in the candle stage (resemble candles). Cut the terminal candles then cut the lateral (side) candles 2-4 inches shorter than the terminal. • Spruce- same as pines • Yews- use heading back. Plant can tolerate up to 50% of plant being removed. Prune in spring and again in early summer.
Broadleaf Evergreens • Rhododendrons, holly, and boxwood require very little pruning. • Remove flowers after they are faded on the Rhododendron to promote dense growth. • Light heading is recommended to keep holly and boxwood dense.
Pruning Tools • Hand pruners or loppers- used for small branches • Pruning saw- are small and have large teeth, used for larger limbs. • Hedge shears- gas powered or electric , shape shrubs in formal gardens.