Urban Forest Hurricane Recovery Program

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:

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 Plan Immediately following storm Step 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 1 Remove 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 2 Stake 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 Up 1. 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 Up 5. 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

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 Plan Immediately following storm Step 1: Remove potential 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

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. Age Estimate by comparing the trunk diameter to the size the species reaches at full maturity. Species Is the species prone to decay? Have poor growth habit? Amount of damage What 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 decayTrees prone to decay Live oak Mahogany Gumbo-limbo Tamarind Laurel oak Royal poinciana Ficus Orchid tree

Good compartmentalizer

Poor compartmentalizer

Species: trees with good structure will require less pruning attention Trees with good structureTrees with poor structure Baldcypress Sweetgum Southern magnolia Live oak Mahogany Red maple Pecan Laurel 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 damage More than 50% canopy loss: Monitor carefully over two year period and decide whether tree is recovering or declining.

Restoration pruning program First 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

Sprouts emerging

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 some Remove some Leave some Once growth slows a bit…

Before After

After first restoration pruning

Restoration pruning program First 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 leaders 1.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

Reduce back to lateral Tie to stake

BeforeAfter

8 months later

Close-up

Begin restoration Before pruning After pruning

Begin restoration Before pruning After pruning 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 program First 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: Urban Forest Hurricane Recovery Program