What is i-Tree?
Last month, as TTF’s Tree Campaign Organizer, I attended a seminar presented by Pennsylvania Community Forests and Penn State. The seminar focused on i-Tree, a software suite of tools, highlighting in particular the i-Tree Streets program which takes a sample inventory of street trees to assess the health of urban forests.
Why does a watershed organization care about trees anyway?
TTF supports tree planting because trees decrease stormwater runoff and pollutants, improving the health of our watershed. Learn more about why trees are good for us here.
Tree inventories? Who needs ’em?
There are a lot of important reasons for a community to have an inventory of its urban forest. Trees are living things that perform jobs just like we do, and inventories provide proof of tree performance just like job evaluations. Sample tree inventories that include the species and DBH (Diameter at Breast Height, about 4 feet from the ground) provide economic, environmental, and health benefits for the trees in the area surveyed.
Inventories tell us that the United States has lost 20% of our tree canopy! They also tell us our Stocking Level, which is the amount of available planting space. Luckily for our Philadelphia neighborhoods,TTF is finding lots of available planting space in West Oak Lane! Read more about our work with Philadelphia Parks & Recreation’s TreePhilly project here.
How can i-Tree help me and my neighborhood?
If you want to do a tree inventory in your neighborhood, you can! The i-Tree software is in the public domain — it’s free! Anyone can download the software, but to do a successful inventory, you need to keep in mind:
* Why am I doing this survey? Have your purpose in mind and know your available resources. Remember that it’s easier to get funding for planting than for care or maintenance. Expect setbacks and plan ahead for them.
* Who will I be working with? This software is user-friendly and volunteer-friendly, but you have to plan for a day’s worth of training. If your volunteers have knowledge of tree identification, that’s an added bonus! Click here to explore the Arbor Day’s interactive ‘What Tree Is That?’ website.
* What am I looking for? Know whether you want to undertake a random sampling of all trees, focus on street trees, or focus on the impact of trees on water quality.
What about my tree?
i-Tree has something for your tree too! i-Tree Design allows you to input your address and information on your street or yard trees. For example, the 10-inch Holly Tree in my front yard will sequester 118 pounds of CO2 and intercept 580 gallons of stormwater annually, saving 36 Kilowatt hours of energy.
What are trees doing for the city of Philadelphia?
Good question! The United States Department of Agriculture (USDA) Forest Service completed an inventory of Philadelphia’s trees in 2007 and concluded that Philadelphia has 15.7 % tree canopy cover (halfway to TreePhilly’s 30% goal!) with an urban forest valued at $1.8 billion!
The three most common species are black cherry, crabapple, and the dreaded tree of heaven! Tree of heaven is a very invasive species, and black cherry and crabapple are relatively small flowering trees. So — Philadelphia needs more large canopy trees and more native species!
I’m just one person… what can I do?
You can volunteer to help get more trees planted!