Visual representation of Tree canopy data

Tree canopy maps shown above, one for Columbia, SC which is at 67% tree canopy, and other with a lower 17% coverage for San Francisco, CA. 

Two facts emerge:: 

• These two cities have different population density
• The parts of town with higher population density also show high degradation in tree canopy in a high scoring city.

These images support the need for a national policy mandating trees, not more than 30 feet apart, on every sidewalk. 30 feet distance between trees is a baseline for contiguous tree canopy, but exceptions can be made for structures already in place and other limiting factors.