Can These Trees Be Saved?
In cooperation with the USDA Forest Service and the International Society of Arboriculture.
A storm can leave trees looking like there's no tomorrow. Major limbs may be broken or damaged, foliage can be shredded or stripped, or the bark may be torn or gouged. But what at first glance may look like mortal wounds are not necessarily fatal to a tree. Trees have an amazing ability to recover from storm damage.
First, Assess the Damage
Before writing off a damaged tree as a “goner,” homeowners should evaluate their trees by asking the following questions:
- Other than the storm damage, is the tree basically healthy and vigorous? If the tree is basically healthy, is not creating a hazard, and did not suffer major structural damage, it will generally recover if first aid measures are applied immediately after the storm.
- Are major limbs broken? The larger a broken limb is, the harder it will be for the tree to recover from the damage. If a majority of the main branches are gone, the tree may have little chance of surviving.
- Has the leader (the main upward-trending branch on most trees) been lost? In species where a leader is important to upward growth or desirable appearance, it may have to be a judgment call. The tree may live without its leader, but at best would be a stunted or deformed version of the original.
- Is at least 50 percent of the tree's crown (branches and leaves) still intact? This is a good rule of thumb on tree survivability. A tree with less than half of its branches remaining may not be able to produce enough foliage to nourish the tree through another season.
- How big are the wounds where branches have been broken or bark has been damaged? The larger the wound is in relation to the size of the limb, the less likely it is to heal, leaving the tree vulnerable to disease and pests. A two- to three-inch wound on a 12-inch diameter limb will seal over with new bark within a couple of years.
- Are there remaining branches that can form a new branch structure? The remaining limbs will grow more vigorously as the tree tries to replace its missing foliage. Look to see if branches are in place that can eventually fill out the tree's appearance.
- Is the tree of a desirable species for its location? If the tree is in the wrong location (such as a potentially tall tree beneath a power line), or an undesirable species for the property (messy fruit, etc.), it may be best to remove it if it has serious damage.
The thumbnail versions of artwork shown in this column depict illustrations that can be downloaded in TIF (.tif) format by clicking on the link below each. They illustrate some of the issues that need to be addressed in determining whether a tree with storm damage can be saved or not.
Then, Make the Decision
The questions listed above will help you make informed decisions about your trees. In general, the answer as to what to do about a particular tree will fall into one of three categories:
1: It's a Keeper
If damage is relatively slight, prune any broken branches, repair torn bark or rough edges around wounds, and let the tree begin the process of wound repair.
An Easy Call: (Illustration b1)
A mature shade tree can usually survive the loss of one major limb. The broken branch should be pruned back to the trunk. In the months to follow, large wounds should be closely monitored for signs of decay.
Minor Damage: (Illustration b2)
Although the tree has been damaged, enough strong limbs may remain on a basically healthy tree to make saving it possible.
Too Young to Die: (Illustration b3)
Young trees can sustain quite a bit of damage and still recover quickly. If the leader is intact and the structure for future branching remains, remove the broken branches and let the tree close over the wounds and recover itself.
2: Wait and See
If a valuable tree appears to be a borderline case, resist the temptation to simply cut the tree down and be done with it. In such cases, it may be best to stand back for a while and think it over. Remember that time is on your side. After careful pruning of broken branches, give the tree some time to recover. A final decision can be made later.
Easy Does It: (Illustration b4)
Resist the temptation to prune too heavily. Remember that the tree will need all the foliage it can produce in order to make it through the next growing season. Remove only the damaged limbs, wait and see what happens.
Hold Off: (Illustration b5)
A healthy mature tree can recover even when several major limbs are damaged. With large trees, a professional arborist should be brought in to assess damage on a borderline situation, and to safely accomplish needed pruning and branch removal.
3: Say Goodbye
Some trees simply can't be saved or are not worth saving. If the tree has already been weakened by disease, if the trunk is split, or more than 50 percent of the crown is gone, the tree has lost its survival edge.
Tree Tragedy: (Illustration b6)
This otherwise healthy young tree has lost too much of its crown the leafy head that is vital for survival. It will probably not be able to grow enough new branches and leaves to provide needed nourishment, and will never be able to regain its former beautiful shape.
Hopeless Case: (Illustration b7)
About all that's left of this tree is its trunk. The few remaining branches can't provide enough foliage to enable the tree to make it through another growing season.
Fond Farewell to a Friend: (Illustration b8)
A rotten inner core in the trunk or structural weakness in branching patterns can cause a split trunk the tree equivalent of a heart attack. The wounds are too large to ever mend, and the tree has lost its sap lifeline between roots and leaves. This tree is all but dead.
Don't Try to Do It All Alone
Some of your trees may have damage that's too close to call, or may have hidden damage. To help with such questions, a tree professional may be needed to help you decide what to do about your trees. Don't hire just anyone who shows up at your door following a storm. Look for qualified arborists in the phone book or by contacting your state or city forester.
For free information about saving trees that have been damaged in a storm, send your name and address to:
The Arbor Day Foundation, 100 Arbor Avenue, Nebraska City, NE 68410.
Please credit artwork as follows: Arbor Day Foundation Illustrations
Click here to download this kit.