tree maintenance: proper tree pruning · pruning us forest service how to guide. additional...

Nancy Stairs

Urban & Community Forestry Program Coordinator

Tree Maintenance:

Proper Tree Pruning

To protect, manage and promote forest resources for the citizens of North Carolina

What will be discussed

What pruning is

Why prune trees

When to prune

How to prune

What will be discussed

What pruning is

Why prune trees

When to prune

How to prune

What is pruning?

Art and science of removing tree parts

for a specific and valid purpose

Science – understanding the tree’s

biological response

Art – understanding the tree’s natural

form and shape

Science: Tree Biology

Removing more than 25%

live crown causes stress to

the tree & a biological

response to produce more

leaves.

Science: Tree Biology

Canopy – Power Plant – Energy (Food)

Trunk and Branches –Storage and Transport

Roots – Receiving Dep’t. – Raw Materials

Big Tree

Inc.

Science: Tree Biology

Pruning live tissue creates a wound

Trees do not heal

wounds, they seal

wounds

Buds produce

growth regulating

hormones

Science: Tree Biology

Art: working with the science

Science: Tree Biology

CODIT

(compartmentalization of decay in trees)

1. Up and Down

2. Inward

3. Side to Side

4. New Wood (Callus)

cfs.nrcan.gc.ca/images/1951

What will be discussed

What pruning is

Why prune trees

When to prune

How to prune

Why Prune?

For a specific and valid purpose

Risk reduction

Tree Function

Tree Health

Tree Form & Structure

Risk reduction

Dead branches

Broken branches or hangers

Split branches

Function

Provide clearance

Improve visibility

Influence flowering

& fruit and nut

production

Directional Pruning

Influence flowering

One Year Later

Tree health

Eliminate rubbing and crossing branches

Remove suckers and water sprouts

Control some insects and diseases

Tree form

Choose leaders

Ensure proper

spacing

Make better

branch angles

Train for future

These also contribute to

tree strength

Restoration

Scheduled pruning to

rebuild structure

(1 – 5 years)

Why to Prune: Terms

Crown cleaning

Crown raising

Crown thinning

Crown reduction

Crown restoration

Training pruning – young trees to ~20 feet

Structural pruning – most effective on young trees

What Most Pruning Boils Down To

Dead, Dying, Diseased, Decayed, Damaged

Rubbing and Crossing Branches

Tight V Branch Union with Included Bark

Some Water Sprouts

Root Suckers from Base of Tree

Types of pruning

Specialty types

Pollarding

Espalier

Topiary

Bonsai

Palm

Shrub

Fruit crop production

Topping is not an acceptable

pruning practice – no matter how

often you see it

Sprouts from a Stub

Tree Response To Topping Cuts

Training Pruning and Structural Pruning

Choose one central leader

Determine lowest permanent scaffold

branches

Ensure good spacing between branches

Select better branch angles

Remember the natural form of the tree

Why Prune Young Trees?

new tree: over several years

Good spacing between branches

6 – 12 inches apart

for small maturing

trees

18 – 36 inches apart

for large maturing

trees

Good branch angles

wider angles =

stronger branch

attachment

Good Branch Angles

Tight angles are weaker

What will be discussed

What pruning is

Why prune trees

When to prune

How to prune

When to prune

Dormant season is best

Dead, damaged, or

diseased - anytime

Avoid just before leaf

expansion

Avoid just before leaf drop

What will be discussed

What pruning is

Why prune trees

When to prune

How to prune

How to prune

1. Establish reasons to prune

2. Use proper tools

3. Don’t top any tree

4. Remember pruning guidelines

5. Make proper cuts

Tools for PruningProper Improper

Eye protection

Sharp!

By-pass style

Matched to size of

branch

Eye protection

Worn out, dull, rusty

Flat anvil style

Hedge trimmers

Chainsaw in

untrained hands

Mowing decks

Hand Tools for Pruning

Coarse toothed saw

Fine toothed saw

Hand pruner

Pole saw/pruner

Loppers

Pruning Guideline: #1

Place cuts correctly

Flush Cuts

Branch collar is removed

Trunk is exposed to

decay and possible

structural problems.

Stub Cuts

Cut beyond branch collar Trunk is exposed to

decay and possible

structural problems.

Pruning Guideline: #1

Place cuts correctly

Flush Cuts

Pruning Guideline: #2

Make cuts correctly

Pruning Guideline: #2

Make cuts correctly

Pruning Guideline: #2

Make cuts correctly

Pruning Guideline #3

Diameter of branch left should be at least ⅓

size of original branch

Pruning Guideline: #4

Remove no more than ¼

of the entire live crown in

a year

better to prune over

time to achieve desired

goal

Pruning & Wound Dressing

Petroleum Based

Seal in Organisms

Retard Callus/Wound Wood Formation

SHOULD NOT BE USED**

** Light coatings & disease vectors

Conclusion

Pruning is art and science of removing

tree parts for a specific and valid purpose

Purpose includes clearance and improving

structure

Dormant season best for pruning

Make proper cuts using proper tools

Place cuts correctly

Don’t top trees

Additional ResourcesTree City USA® Bulletin

No. 1ISA publication – Best

Management Practices: Tree

Pruning

US Forest Service

HOW to guide

Additional Resources

An Illustrated Guide to Pruning by

Ed Gilman

The Pruning of Trees, Shrubs and

Conifers by George E. Brown

Thank You

Questions?

Nancy Stairs

Urban & Community Forestry Program Coordinator

NC Forest Service

nancy.stairs@ncagr.gov