Tree roots stabilize the soil and prevent erosion.
City Trees & Municipal Code
The City of Pittsburgh has municipal code that protects trees, allows for the creation of the Pittsburgh Shade Tree Commission and requires developers to plant trees as part of new construction.
A complete list City codes can be found here (http://www.municode.com/library/PA/Pittsburgh).
Chapter 483 deals with the care and maintenance of public trees. Did you know that it is against the law to post signs /posters to trees? Or did you know that as a street tree grows, property owners are required to increase the permeable area around the base of the tree? This chapter covers these basics as well as the maintenance and removal responsibilities of DPW.
Chapter 485 is tilted Protection. This chapter outlines protection measures of public owned trees. The City may seek compensation from anyone who damages a public tree. Protections outlined in this chapter include from construction damage, excavation, gas leaks, even damage to trees by pets. Pets can cause lot of damage to trees: pet owners may tie their pet to a tree and cause bark and trunk damage; pets may climb trees, snapping branches; and pet waste does a great deal of damage to the soil structure/function as well as causes direct damage to the trees truck and roots.
Chapter 918 deals with developments and landscaping requirements. For off street parking 1 tree for every 5 parking spaces must be planted. And for new buildings, a street tree must be planted every 30 feet. This chapter outlines many other City codes that require dumpsters to be screened to how many square feet of landscaping must be included around parking lots.
The City of Pittsburgh does have a progressive code when it comes to trees. Trees are a vitally important resource in our City and must be protected, preserved and re-planted as our City grows.