Urban Forest Hurricane Urban Forest Hurricane Recovery ProgramRecovery Program

http://treesandhurricanes.ifas.ufl.edu

Restoring trees after a hurricane

Edward F. Gilman and Traci Jo Partin.

Know when to restore…

Assess damage first before deciding to restore.

To learn about which trees can be restored and which should be removed, refer to our website:

http://treesandhurricanes.ifas.ufl.edu

How long does restoration take?A tree requires 2-5 years or more to

restore depending on various factors:

• Size of tree- smaller trees take less time to recover

• Age - mature trees will require more time and maintenance

• Species - decay resistant trees will recover better

• Amount of damage - more damage done = more time and visits

Restoration pruning

1. After the hurricane: Develop a response plan

2. A few years later: Implement a multi-year

restoration pruning program

Response PlanImmediately following stormStep 1: Remove hazards

Step 2: Stake fallen trees where possible

Step 3: Clean canopies of damaged trees

Before the next visit• Allow trees to regenerate energy reserves

• Develop a tree management program in the community

Immediately following storm: Step 1Remove all hazards:

- Fallen tree or branch near power lines

- Broken, cracked, and hanging limbs located near property

- Large, fallen trees blocking traffic areas

DANGEROUS! Only experienced workers should handle these situations!

Immediately following storm: Step 2Stake fallen/leaning trees when possible:

• Small trees (approximately 4 inches trunk diameter or less) OR• Recently planted

Do not let the roots dry out! Water and cover with tarp until tree can be re-planted.

How to Stand a Tree Up1. Keep roots moist.

2. Excavate the hole to accommodate roots.

3. Cut jagged or torn roots with sharp tools, making clean cuts.

4. Pull tree up and backfill with site soil.

Take measures to protect the trunk.

Do not plant deep.

How to Stand a Tree Up5. Water as if the tree were

recently planted. Irrigate 3x a week with 3 gallons/inch trunk diameter. There is no need to fertilize at this time.

6. Stake the tree. Adjust stakes and remove when tree is stable.

Immediately following storm: Step 3

Clean canopies of damaged trees:

Remove broken, hanging stems first so that branches do not fall and cause injury.

lateral

lateral

Canopy Cleaning

Make clean cuts on stubs, breaks, and tears.

Reduce back to lateral branch if one is present.

Heading cuts are used when no laterals are nearby

Heading cut

Example of tree after canopy cleaning

Do not top your trees!Topping severely reduces the entire canopy of a tree, cutting large limbs back to stubs.

This practice is very harmful to the health of the tree.

Canopy cleaning on palms• Remove broken, hanging, or

dead fronds that could fall and hit a target

• Leave bent green fronds attached to palm until new fronds emerge fully

• Leave fronds that are yellowing or have brown tips. Establish fertilization program to correct nutrient deficiencies

Palm cleaning

Leave live fronds

Remove dead fronds

Leave green, bent fronds

Remove broken fronds that are smothering the bud

• Remove dead and hanging fronds

• Leave yellowing fronds attached

• Overpruning leads to

stress and decline

Response PlanImmediately following stormStep 1: Remove potential hazardsStep 2: Stake fallen trees where possibleStep 3: Clean canopies of damaged trees

Before the next visit• Allow trees to regenerate energy reserves• Develop a tree management program in the

community

Allow time for sprouting so that trees can regenerate energy reserves.

How long?

Deciduous and broadleaf evergreen trees:

• Trees should begin sprouting by spring of the year following the hurricane (April for hardiness zones 9-11).

• Wait until sprout growth slows before next pruning visit.

Pines• Pines do not sprout.

When all of the needles are brown, the tree will not recover.

• Remove

Palms• Allow at least 6 months after the storm for palms to

put out new growth.• Approximately 1 to 2 years before palms appear

normal with a full canopy.

Develop a tree management program

• Work with homeowners and community planners to create a tree management program that allows routine arborist visits.

• Regular pruning will build strong tree structure and minimize failure in future storms.

Restoration outline

1. After the hurricane: Develop a response plan

2. A few years later: Implement a multi-year

restoration pruning program

Factors that affect restoration• Size of tree

Large maturing shade tree vs. small, ornamental tree.

• AgeEstimate by comparing the trunk diameter to the size the species reaches at full maturity.

• SpeciesIs the species prone to decay? Have poor growth habit?

• Amount of damageWhat percentage of the canopy is damaged?

Pruning program: large maturing trees

Time needed

to restore:

Young (under 10” dbh*)

Medium-aged (10-20” dbh)

Mature (over 20” dbh)

• 2 – 4 yrs. • about three visits

• 3 – 5 yrs.• three to five visits

• 5 + yrs.• five or more visits

* dbh – diameter at breast height** These measurements are approximations to help determine age, but vary with species and growth rate.

Pruning program: small, ornamental trees

Time needed

to restore:

Young (under 5” dbh)

Medium-aged (5-10” dbh)

Mature (over 10” dbh)

• 2 – 3 yrs. • about two visits

• 3 – 4 yrs.• about three visits

• 4 + yrs.• four or more visits

* dbh – diameter at breast height** These measurements are approximations to help determine age, but vary with species and growth rate.

Species: trees that resist decay make better candidates for restoration 

Trees that resist decay Trees prone to decay 

Live oakMahogany

Gumbo-limbo Tamarind

Laurel oakRoyal poinciana

FicusOrchid tree

 

Good compartmentalizer

Poor compartmentalizer

Species: trees with good structure will

require less pruning attention Trees with good structure Trees with poor structure

 BaldcypressSweetgum

Southern magnoliaLive oak

MahoganyRed maple

PecanLaurel oak 

Weak vs. Strong

Amount of damage

50% canopy damage

► Come back after two years

30% canopy damage

► Come back after one year

Amount of damageMore than 50% canopy loss: Monitor carefully over two year period and decide whether tree is recovering or declining.

Restoration pruning programFirst visit (1 - 2 years after storm or later)

Sprout management“reduce some, remove some, leave some”

Second, third visits (space visits 1 year apart)Establish a new leader at the ends of broken stems through continued sprout management

Later visits (~ 4 years after storm)Preventive pruning to reduce and remove codominant stems

Sproutsemerging

Over time, sprouts develop woody stems and can grow into strong lateral branches

…but they need your help!

Reduce some- Shorten 1/3 of the sprouts. They will continue to store energy, but will eventually be removed.

Remove some- Remove 1/3 of the sprouts to allow space for the most vigorous ones to grow.

Leave some- These will develop into the new branches.

Sprout management

Reduce someRemove someLeave some

Once growth slows a bit…

Before

After

After first restoration

pruning

Restoration pruning programFirst visit (1 - 2 years after storm or later)

Sprout management“reduce some, remove some, leave some”

Second, third visits (space visits 1 year apart)Establish a new leader at the ends of broken stems through continued sprout management

Later visits (~ 4 years after storm)Preventive pruning to reduce and remove codominant stems

Establishing new leaders1. During canopy cleaning, make

pruning cut on limb

2. Let branches sprout

3. After sprout growth slows, reduce some, remove some, leave some

4. Select sprout to be the new leader.

- Look for lateral branches and collar

The swelling at the base of the branch is called a collar.

Presence of a collar indicates a strong attachment.

Establishing new leaders

• New leaders can seal over damaged tips on broken stems 4 inches or less in diameter

• Larger stems (2 - 4 inches) = more time and sprout management

Storm breaks off top

Storm breaks off top

Reduce back to lateral Tie to stake

Before After

8 months later

8 months later

Close-up

Begin restoration

Beforepruning

Afterpruning

Begin restoration

Beforepruning

Afterpruning

Notice that there are two sprouts at the same point.

One will be removed later so the other can dominate.

Top two branches removed with one cut

One year after initial damage

Restoration pruning programFirst visit (1 - 2 years after storm or later)

Sprout management“reduce some, remove some, leave some”

Second, third visits (space visits 1 year apart)Establish a new leader at the ends of broken stems through continued sprout management

Later visits (~ 4 years after storm)Preventive pruning to reduce and remove codominant stems

To learn about preventive pruning…

Visit Ed Gilman’s website:

http://hort.ifas.ufl.edu/woody

Urban Forest Hurricane Recovery Programhttp://treesandhurricanes.ifas.ufl.edu