It is important to study the ecological and economic functions
because municipalities and other governmental agencies are
interested in benefits, such as air pollution reduction and stormwater
runoff control, provided by urban forests. While this category
of functions should be emphasized, the visual effects of urban
forests cannot be neglected. As Nowak (1994a) pointed out, efforts
to enhance one function may impair other functions, and urban
forestry plans and programs need to address the overall functions
of urban forests