Transportation corridors are major infrastructure elements of today’s cities, and actions by transportation designers and planners have great influence on social ecology and community. City streets are not simply thoroughfares for motor vehicles, but must also serve as public spaces where people walk, shop, meet, and generally participate in the social and recreational activities that make urban living enjoyable. Urban foresters, designers, and planners encourage streetscape tree planting to enhance the livability of urban streets.

In addition to their aesthetic value and ability to contribute to the character of the city, trees and landscape features along the roadside have a positive effect on “driver” behavior and perception. This results in better safety performance, stress reduction and way finding, where nodes and streets can be marked by distinctive landscape elements using different trees or new colors. So the “driver” can realize and feel his whereabouts, where to slow down or to turn around, as well as the through landscape unity or variety.

Furthermore, to be effective, roadside landscape design must:

• Recognize that the roadside is dynamic, and assess what is most needed, while anticipating what will be needed many years from now
• Integrate highway safety concerns with a greater appreciation for soil, vegetation, maintainability, and financial responsibility
• Ensure highway drainage and sustainable landscape plantings, while controlling invasive species and developing strategic approaches to replanting
• Promote efficient low-maintenance landscapes, and encourage the development of meadows and reforested areas that can be managed with limited resources