​i-Tree is a software suite from the U.S. Forest Service that provides urban forest analysis and benefits tools. i-Tree helps quantify the structure of trees and forests to determine the benefits that trees provide. i-Tree Canopy is  a tool within i-Tree that is used to provide a basic, but useful assessment of the tree canopy in a given area. 

The i-Tree Canoy process involves the following:

• Drawing of a project boundary onto Google Maps or loading of an ESRI polygon shapefile
• i-Tree Canopy randomly generates sample points and zooms to each one so you can choose from your pre-defined list of cover types for that spot.
• 500-1000 survey points are suggested; the more points you complete, the better your cover estimate for your study area.

Tree canopy and benefits are then estimated by i-Tree based on the results of the analysis. 

I utilized i-Tree Canopy to assess the tree canopy within the Buena Park neighborhood of Chicago, in which I live. The map below shows the boundary of Buena Park, along with a few of the sample points used in the analysis. I included only the parts of the neighborhood west of Lake Shore Drive, as these are the inhabited portions. 

Tree Canopy Percentage
i-Tree Canopy analysis showed that about 16.6% of Buena Park is covered in tree canopy, This is below the average of 21% for the entire Chicago region determined through a 2013 study, This is not too surprising, since the whole-Chicago study included dense urban areas like Buena Park but also more natural areas such as forest preserves. 16.6% canopy is therefore respectable given the urban nature of the neighborhood, and likely higher that most other areas in the city of Chicago. 

Tree Canopy Benefits
Other benefits of urban trees measured by i-Tree Canopy include carbon sequestration, ozone removal and particulate matter removal. The total benefit for each of these, measured in amount removed and dollar value, is below:

Carbon Dioxide sequestered annually in trees - 148.66 tons ($5,378.80)
Carbon Dioxide stored in trees - 3,748.16 tons ($135,632.54)
Ozone removed annually -  1,460.18 lb ($102.19)
Particulate Matter less than 2.5 microns removed annually - 70.95 lb ($211.25)

I plan to further study the tree canopy of Buena Park to determine available public and private tree planting spaces, as well as ideal location for future tree planting. My goal is to determine the best places to plant trees in the neighborhood to maximize the return on investment of tree planting funds.

This past summer, the Green Building Certification Institute (GBCI) officially launched the Sustainable SItes Initiative (SITES) rating system. GBCI is the organization that certifies LEED projects and accredits LEED professionals. SITES addresses many of the landscape and site issues that are vital to sustainability outside of the physical building.

From the SITES website - "The Sustainable Sites Initiative is a program based on the understanding that land is a crucial component of the built environment and can be planned, designed, developed and maintained to protect and enhance the benefits we derive from healthy functioning landscapes."













We've been hearing about SITES for a few years now. It's development began in 2006, through a collaboration between the Lady Bird Johnson Wildflower Center, United States Botanic Garden and the American Society of Landscape Architects. A 2 year pilot recently certified 46 projects across the country.

Being an arborist and urban forester, I am largely interested in how SITES concerns trees. Broadly, the topics of climate change, biodiversity and resource depletion concern urban trees. Specific credits concern the topics of landscape water use, managing precipitation on site, native plants, urban heat islands and energy use around buildings. These are all marked improvements from any LEED rating system, which only gives minimal attention to the landscape. How effective these credits are at achieving their intended goals will be seen as more SITES projects are registered, but I am hopeful that they will make projects both more environmentally sustainable and marketable.

I look forward to having the opportunity to learn more about SITES and hopefully work on some projects under the new rating system.