MANAGING STORM-DAMAGED TREES

Steps for managing a community forest after a major storm:

STEP 1 Cleanup of downed trees and limbs For large volumes, use methods established for tasks like trash pickup or snow removal.  Excellent resources on the FEMA website.

                                STEP 2 Communication

It is crucial to work with the media early and often. Spread these messages: 1) be safe, 2) don’t panic, 3) get certified, insured, and professional help. Also, people tend to become radical about trees after a disaster, wanting to "kill" or "save" them all, and need to hear voices of reason.  Useful material available from the National Arbor Day Foundation.

STEP 3 Elimination of immediate threats to public safety Priority 1 removal. Identify trees that are 1) uprooted, 2) split in half, or 3) undermined, and select them for removal if they have a building, sidewalk, electric wires, or road as a likely target. Distribute work orders for the immediate removal of these hazardous trees.

Priority 1 pruning. Systematically do required pruning street by street, taking out limbs that are 1) hanging, 2) broken, or 3) cracked, if they have a building, sidewalk, electric wire, or road as a likely target. Bidding out the work for these steps is often easy and cost-effective.

ice blocking road   

                                                                        Road blocked with ice-downed limbs
                                                                                          (Source: http://www.fs.fed.us/na/durham/ice/)
                       
STEP 4 Planning Inventory. Now you will need a survey or inventory of your forest to see all the damage and estimate its cost. Download free inventories, or buy a professional program. An inventory will make managing trees, budgets, and labor much easier in the future.

Inspection. Systematically inspect each tree, and determine hazard potential, maintenance needs, and site information. Here is one well-tested simple formula for hazard potential (Matheny/Clark, 1994, Photographic Guide):

HAZARD POTENTIAL = failure possibility + part size + target rating

Assign each category on the right side a number between 1 and 4, with the higher numbers being more serious. Good hazard evaluation requires training and experience, and is best done by professionals. If you do it yourself, be consistent.  When the inventory is done, prioritize your work by the tree's hazard potential, ensuring that the most serious problems will be eliminated first.

Policy. This is a good time to get in place a full plan that includes 1) up-to-date specifications for selecting, buying, and planting; 2) a Tree Ordinance; 3) a Tree Board of people from public and private spheres. Seek out help for replanting from private and public funds.

Education. Work again with the media, now that you have a plan. It is important that people know what the next actions will be, and on what basis they will be decided. Be sure to notify homeowners from now on before doing work on their tree.

STEP 5 Reduction of delayed threats to public safety Priority 2 removal. This is probably the hardest and most controversial step in managing a storm-damaged forest. Get help if possible. You want to decide which trees should come down now to remove a source of future hazards, and to be more cost-effective. You need to balance safety, looks, neighborhood effect, cost, and species. Priority 2 removal candidates:

1) trees with 50% or more of the crown destroyed or heavily damaged, especially when the loss is mostly on one side

2) trees with leaders (major limbs) broken back into the trunk

3) split or tipped trees that were not removed as Priority 1.

The best candidates for Priority 2 removal are large weak-wooded species that have a history of failure.  In the Northeast, such species include basswood, black locust, boxelder, cottonwood, poplars, tre-of-heaven, silver maple, and willows.

Priority 2 pruning. Storm-damaged trees are weakened trees, and will sometimes continue to cause trouble over a long period. Use your inventory to locate trees with a high hazard rating and great maintenance needs.  Prune off stubs of broken branches, and begin a system of maintenance pruning to reduce potential hazards. Except for high-hazard species, it is often more cost-effective to have a professional clean and repair Priority 2 trees, than to remove them and replant.

Delayed damage. New signs of serious damage will often show up months later. After a winter storm, for instance, be ready for failures of split limbs when leaves come out in the spring.

Where can I get more info?

Hauer, Richard J., et al.  1994.  Trees and ice storms: the development of ice storm-resistant populations.  Special Publication 94-1.  Urbana IL: Illinois Dept. of Forestry.  Bond, Jerry.  2000.  Tree emergency manual for public officials.  Produced by the Northeast Center for Urban and Community Forestry.  For other information, advice and help on this topic, call offices of your State Urban Forestry Coordinator or University Extension service, visit urban forestry web sites.