For each theme a web page describes past research, summarizing up to 300 articles. The narrative starts with evidence-based bullet points that city foresters can use in their advocacy work. For instance, under “Community Economics,” you can find these “fast facts”:
• The presence of larger trees in yards and as street trees can add from 3% to 15% to home values throughout neighborhoods.
• Averaging the market effect of street trees on all house values across Portland, Oregon yields a total value of $1.35 billion, poten- tially increasing annual property tax rev- enues $15.3 million.
• Shoppers claim that they will spend 9% to 12% more for goods and services in central busi- ness districts having high quality tree canopy.
• Shoppers indicate that they will travel great- er distance and a longer time to visit a district having high quality trees, and spend more time there once they arrive.
Green offices and classrooms appear to boost work productivity and education performance in the places where we spend many hours each day. Photo by Guy Kramer
In total we have collected more than 1,700 research publications that span nearly 40 years of research. Most of these articles are difficult to access by city foresters, as they are distributed across the academic journals of many disciplines. Nonetheless, each research summary is extensively referenced so that the reader can identify the source studies.
Law enforcement officials may regard vegetation as a contributor to social disorder and crime. Research tells a different story when people green their community then take pride in a public special place. Photo by Kathleen Wolf
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