What is a tree inventory?

A tree inventory is the gathering of accurate information on the health and diversity of the community forest. How many street trees are there? What kind? In what condition are they? You cannot manage the community forest effec- tively unless you know its condition. Tree inventories are an essential tool of good management.

Why should my community do a tree inventory?

There are many good reasons for doing a tree inventory in your community. The inventory may be used:

What information should be collected during an inventory?

Only data that will be put to use should be collected. Your community must determine what objectives it wishes to achieve prior to conducting an inventory. Bear in mind that information translates into expense: the more data gathered on each tree, the greater the cost of the inventory. Generally however, information on the following is collected:

What type of inventory should my community do?

There are many different types of inventories and you should select an inventory type only when you know precisely what you want to accomplish. Data gathered on your communitiy's trees must have practical value. To guarantee that your tree management program will be effective today and useful tomorrow, you must match an appropriate inventory to your objectives. The most common types include:

How should the inventory be done?

The tree inventory may be done by professionals or volunteers, but, in either case, all crews, regardless of experience, require training before and during the inventory. (Please note that it is advisable that the municipal tree warden assist or lead the tree inventory process. It is also advisable that a person trained in hazard tree assessment review all trees surveyed and assess them for hazardous condition.)

Individuals working alone tend to be more productive, but crews attract attention, and this fact may be exploited to good advantage: professionals who carry brochures about the tree management program and the inventory can educate community residents. Crews should wear uniforms if possible and carry identification cards. Where crime is a problem, two or more people must work together for safety.

When should the inventory be done?

During the summer favorable weather makes inventory work more pleasant and students are often available to help, On the other hand, winter conditions allow crews to observe trees for hazardous limbs and dead wood. Professional foresters often choose to conduct inventories in the winter.

How should the inventory be updated?

Tree populations undergo constant change, and, as an inventory ages, it becomes less accurate and useful. No inventory will provide information that is useful beyond five or ten years. Consider the damage a single storm can do. Hurricane winds can render an inventory obsolete overnight. The ideal way to keep the inventory current is to make use of specially designed computer programs that provide easy and logical locations for data entry specific to tree inventories. Good programs also allow you to easily query data and produce reports, graphs, tables and perform some statistical analysis.

Hazardous trees

Stress conditions exist in the community firest severely affecting health of individual trees. Those trees that pose a hazard to public safety need to be detected and treated by removal or pruning as soon as possible. It is prudent that the municipal tree warden assess trees for hazardous conditions frequently.

Robert M. Ricard
Extension Educator, Urban and Community Forestry
West Hartford Extension Center
1800 Asylum Avenue
West Hartford, CT 06117