Most urban forests were not planned, they just happened. This does not mean that they cannot or should not be planned, but rather that we should learn from the clues and lessons found within these naturally occurring urban forests. The majority of all communities have “open-space” plans, park and recreation plans, and – to some degree – street tree programs. Seldom are these plans coordinated or comprehensive with respect to urban forest resources.

Three basic questions should be addressed with any planning effort: What are the objectives; what is being planned; and who is responsible? The complexity of urban forestation becomes readily apparent as answers are sought to these questions.

• What are the objectives?

It is of utmost importance to determine what a community is willing to do to achieve the desires of its objectives. Objectives may be singular in nature or multifaceted. Either objective may result in multiple benefits. For example, simply planting an urban forest can greatly enhance its immediate surroundings with improved air and water quality, among other things. A more complex objective will have a more diverse and widespread impact, but both are beneficial within the community at different levels.

• What is being planned?

The nature and composition of the urban forest has been described in a number of ways. The following is an adaptation of an encompassing definition developed by the Washington State Department of Natural Resources: “The urban forest is the land in and around areas of intensive human influence, ranging from small communities to dense urban centers, that is occupied or potentially occupied by trees and associated natural resources. Urban forest land may be planted or unplanted, used or unused, and includes public and private property and street, transportation and utility corridors.” This is a compelling definition, because it not only describes what the urban forest is but also what it might become.

When dissecting this definition, the urban forest is not simply street trees and parks, but rather an ecosystem that includes soil, water, animals, utilities, buildings, transportation systems, people and of course, vegetation. Vegetation includes all plants – woody and herbaceous – regardless of where they are growing; private yards, parks, school grounds, etc.

• Who is responsible?

In general, planning should be a participatory process. However, someone needs to assume responsibility. The lack of responsibility can and will hinder a comprehensive approach to urban natural resource planning. However, the issue of responsibility needs to be addressed on many levels; ownership, regulatory authority, investment, management and the establishment of policy.

Because of its implication with respect to control, ownership is a very critical point. The extent to which ownership is privately or publicly held will directly determine investment and management strategies as well as public policy. The assumption is generally that the higher the population density, the greater the percentage of publicly owned urban forest.

In dense urban areas, public trees represent a significant portion of the urban forest. Therefore, in these communities, the health of the urban forest is highly dependent on the level of public commitment and investment. Wide-reaching and strongly supported urban forestry programs are a key component in “green“ infrastructures.

On the other hand, privately-owned urban forest resources depend on regulatory mechanisms for protection and enhancement. Regulatory mechanisms include things such as zoning codes and landscape and tree ordinances. Since ownership tends to increase with decreased density, this would support the need for regulatory techniques. Regardless of density or ownership issues, communities need to develop a publicly supported urban forestry program and establish appropriate regulatory measures.