4.5.1 Applications and Limitations

Applications and limitations for individual retained or planted trees on developed sites include:
  • Properly planted, new and existing trees can intercept precipitation and reduce associated surface flow on streets, parking lots, sidewalks, and plaza areas.
  • Tree crown growth can be restricted by adjacent structure or overhead utilities.
  • Inadequate underground rooting space can impair growth and cause premature mortality (Lindsey and Bussuk, 1992; Grabosky and Gillman, 2004).
  • Adequate soil volume and quality are needed for trees to reach a healthy mature size.
  • Trees surrounded by or located near impervious surfaces can experience limited soil moisture, nutrients and gas exchange.
  • Larger mature trees provide more stormwater (and other) benefits than small trees (see Figure 4.5.2).
  • Appropriate drainage is needed to ensure the growth of healthy trees (Urban, 2008).
  • Trees should be protected when located near plowed snow storage areas.

Fig 4.5.2
A bioretention facility utilizing existing mature street trees. Source: AHBL, Inc.