What is Meant by Urban Forestry? - What is an Urban Forest?

In its most uninteresting definition an urban forest is the sum of all woody and associated vegetation in and around dense human settlements, ranging from small communities in rural settings to metropolitan regions.

You don't find burly lumberjacks in hard hats with chain saws regularly cutting down trees in an urban forest. Urban forests can be those single trees amid tall skyscrapers that contribute to the beautification of our cities, but also contribute to the welfare of our environment.

National Urban Tree Deficit

In 1986, the National Urban Forest and Community Advisory Council (NUCFAC) conducted a survey to understand the condition of the nation’s street trees, based on a 20-city survey. The first, “State of Our City Forests” (American Forests Magazine June, 1986) reported that urban forests in those cities were in decline, with the average city losing 4 trees for every one planted.
In 1991, American Forests (formerly known as the American Forestry Association) conducted a follow up survey of 20 cities. The findings revealed the continued decline of city street trees, including the alarming statistic that the average life of a downtown street tree is just 13 years.

An estimated 634,407,719 trees are currently missing from metropolitan areas across the United States as the result of urban and suburban development. These calculations are based on American Forests' Urban Ecosystem Analysis report conducted over six years in ten select cities. Using satellite imagery, American Forests has been able to document the decline of city trees in areas across the United States.

What’s an Urban Tree Worth?

In 2003, the Cedar Fire affected 28,466 acres of land within the San Diego city limits, about 13% of the entire city. Comparing pre- and post-fire conditions in the Cedar Fire area, American Forests reported a loss of 49% tree canopy and 73% each of chaparral and shrub. This loss in vegetation resulted in decreased ecosystem services: Within the Cedar Fire area, storm water runoff increased by 12,674,490 cubic feet. The value of retaining this additional storm water, replacing what the trees did for free, is estimated at $25,349,000. The ability of the lost canopy to remove air pollutants decreased by 314,870 pounds per year, a loss in value estimated at $798,000 annually.

The California Urban Forestry Act of 1978 recognized the value of trees in the urban environment and directs the Department of Forestry and Fire Protection to manage them.

The San Diego County Cedar Fire in 2003 had a significant deleterious effect on air quality, water quality and storm water runoff. These changes are described quantitatively in a report published by AmericanForests.org.