How to compute the presence of foliage in public spaces

For the 3-30-300 guidelines, the rule indicated by the "30" is that 30% of the environment must have foliage coverage. This can be computed in the Tygron Platform by creating a determination of publicly accessible space, and then calculation how much of that space also has foliage coverage.

Editor → Current Situation (Ribbon tab) → Overlays (Ribbon bar)

How to compute the presence of foliage in public spaces:

1. Create a Grid Overlay which highlights which locations are to be considered "public space", such that:
   Locations which are not public have a value of 0.
   Locations which are publicly accessible have a value of 1.
2. Add a Heat Overlay.
3. Set the result type of the Heat Overlay to Foliage.
4. Add a Combo Overlay, configured so that:
   Input A: The public space Overlay.
   Input B: The Foliage Overlay.
   Formula: IF(EQ(A, 0), NO_DATA, GT(B, 0))
5. Configure the legend of the Combo Overlay to have a distinct entry for the value "0" and the value "1".

Notes

• The result is a map of foliage in public space, but does not yet make a judgement about whether it qualifies as "sufficient" (30%). That requires an additional calculation:
  • Using an Indicator, it is possible to query the average value of the resulting Combo Overlay, which equals the fraction of the Neighborhood's public space which is covered by foliage. If that fraction is equal to or greater than 0.3, the target of 30% is achieved.
  • Using an Average Overlay, it is possible to compute a localized fraction of green within a certain radius. The result is an Overlay which for each arbitrary location shows the fraction of public space which is covered by foliage. If that fraction is equal to or greater than 0.3, the target of 30% is achieved.
• The Heat Overlay's Foliage result type allows for an easy way to obtain proper foliage for any given Project area. It does not require anny specific configurations for the complete heat calculation.
• The consideration of what is or isn't public space can vary between organizations and use-cases. It is recommended to use a pre-obtained dataset of what is or isn't public space. If that is not available or a more dynamic calculation is desired, it is possible to use multiple Average Overlays and a Combo Overlay to include or exclude locations which have certain Attributes present, such as PRIVATE_YARD or SOLID.

See also

• Demo 3-30-300 Project