Greenness vs. Income 

Results

The choropleth map shows definite spatial clustering around high levels of greeness in Santa Clara County tracts.  Moran's I confirms spatial clustering (I = 0.22, p = 0.001). Greener neighborhoods cluster together and have higher Greenness values. People put a high value on houses in green spaces with tree canopy. 

Policy Implications
Tree canopy in urban and suburban environments has many health and well-being benefits that people buy into when they pay high prices for houses. It’s also possible that high house prices drive greenness, or are driven by greenness. In many places in Santa Clara County, trees were left in place as neighborhoods were developed–these areas still benefit to this day from the original forest canopy, such as in downtown Palo Alto, and Professorville. Other cities were built on orchards and agricultural lands that lacked the original live oak and valley oak canopy. It's hard to tell from this analysis if trees raise home prices, or home prices protect trees. Some cities also have policies that either sponsor or penalize tree canopy. Since greeness is highly correlated with house values, cities should encourage tree canopies if they want to collect higher parcel taxes. This financial benefits is in addition to the actual values that tree canopies bring to neighborhoods in terms of carbon fixation, water cycling, air filtration, oxygen production, and temperature regulation.