What does that mean?

• Hazard evaluation means a careful inspection of problems and ranking of solutions for community trees with 1) a potential to fail, and 2) a target they can hit.
• Such evaluation requires experience and knowledge to be done well, though it is difficult to predict which trees will actually fail

Why should you bother?

• To avoid hurting people and damaging property by 1) identifying hazard trees and taking appropriate action, and 2) managing trees in a reasonable and responsible manner.

Who does that kind of work?

• Professionals. Urban foresters, certified arborists, or other knowledgeable and reputable tree professionals, can supply reliable decisions on most common problems.

• Amateurs. Observant and responsible individuals can be trained to work with municipal tree managers. They can 1) make annual inspections, 2) note evident hazards, and 3) suggest a need for more expert inspection.

What do you look for?

• You have to look for external defects, and guess about internal problems, examining

-- the crown for undersized, discolored, or missing leaves that can point to problems above or below the ground you might not otherwise see;

-- the branches and trunk for dead wood, breaks, holes, weak attachments, bad wounds, growing plants, fungal conks, and bleeding, split, or included bark;

-- the base for lack of flare, cavities, loose bark, sawdust, damaged buttress roots, soil mounding, or mushrooms.

When should it be done?

• The main point is that you should be doing it, and any time is better than none.
• Certain seasons are more productive than others:

-- Winter is the easiest time to examine the branches and trunk for defects, since all sides are visible (though you need binoculars) when the leaves are absent;

-- Late Summer is a good time to check the tree crown for signs of a problem, since heat and drought will usually stress weak trees before strong trees;

-- Early Fall is the best time to look for disease in the branches, trunk or base. Tree fungal infections are easiest to spot and identify from the fruiting bodies they produce toward the end of the growing season.

Where can I get more information?

"How to Recognize Hazardous Defects in Trees" (1996, USDA Forest Service), available from your local Cooperative Extension or DEC office, and also from the Community Forestry Education Project at Cornell Cooperative Extension--Monroe County (716-461-1000).