An obstacle to making cities more sustainable with shade trees is inappropriate planting details resulting in short-lived trees in urban conditions. The average length of survival of a new street tree in New York City is seven years. The short life span means that trees do not grow large enough to provide climate control through shade, nor to reduce and slow rain run-off, nor to clean the air. Yet ineffectual installation techniques persist. Arnold Associates' method of planting urban trees is the singly reliable, truly sustainable way proven to date to establish long-lived healthy city trees. The examples below show some of the special installation procedures and the results ten or more years later. This methodology was developed over 30 years ago and has been successfully employed on many projects since that time.