Davey Tree Expert Company must be feeling really happy at the moment. i-tree, a software program, they designed with the US Forest Service & released to the market in 2006 has become an item of huge interest over the last couple of months. Deservedly so too, as the program is a fantastically useful tool that can be downloaded by anyone free of charge. Instruction manuals can be downloaded free of charge as well.
Tree Hugger has recently written about the i-tree software as well as a number of other high profile green websites. There is much excitement in the media about i-tree. This surprised me because the i-tree software has been around for nearly 5-years. The recent interest clearly demonstrates an attitude that is pro street tree.
i-tree can be used to calculate the value of a single tree or the value of the trees across a whole city. It can be used a teaching tool by schools or as a professional assessment tool by councils, industry, arborists, landscape architects, anyone really.
“The i-Tree software suite v. 3.0 includes two flagship urban forest analysis tools & three utility programs.
- i-Tree Eco provides a broad picture of the entire urban forest. It is designed to use field data from randomly located plots throughout a community along with local hourly air pollution & meteorological data to quantify urban forest structure, environmental effects, & value to communities.
- i-Tree Streets focuses on the ecosystem services & structure of a municipality’s street tree population. It makes use of a sample or complete inventory to quantify & put a dollar value on the trees’ annual environmental & aesthetic benefits, including energy conservation, air quality improvement, carbon dioxide reduction, stormwater control, & property value increases.
- i-Tree Species Selector is a free-standing utility designed to help urban foresters select the most appropriate tree species based on environmental function & geographic area.
- i-Tree Storm helps you to assess widespread community damage in a simple, credible, & efficient manner immediately after a severe storm. It is adaptable to various community types & sizes & provides information on the time & funds needed to mitigate storm damage.
- i-Tree Vue (Beta) allows you to make use of freely available national land cover data maps to assess your community’s land cover, including tree canopy, & some of the ecosystem services provided by your current urban forest. The effects of planting scenarios on future benefits can also be modelled.”
To access the i-tree software program, go to – www.itreetools.org
The instruction manuals can be downloaded here – http://www.itreetools.org/resources/manuals.php
There is another free computer modeling program developed by the United States Department of Agriculture Forest Service in the late 1990s called Urban Forest Effects or UFORE. UFORE calculates the structure & environmental effects of the urban forest as well as the dollar value of the urban forest. http://www.ufore.org/
Then there is STRATUM designed by the US Forest Service & released in 2005 -
“STRATUM is a new street tree management & analysis tool for urban forest managers that uses tree inventory data to quantify the dollar value of annual environmental & aesthetic benefits: energy conservation, air quality improvement, CO2 reduction, stormwater control, & property value increase. It’s an easy to use, computer-based program. It allows any community to conduct a street tree inventory. The baseline data provided can be used to effectively manage the resource, develop policy & set priorities. Using a sample or an existing inventory of street trees, this software allows managers to evaluate current benefits, costs, & management needs.”
The New York City Parks Department used STRATUM to value their 600,000 street trees at US$122 million. This was 5 times the value of yearly maintenance. The City of Pittsburgh calculated in 2005 that it received US$2.94 in benefits for every US$1 sent on its urban forest. The monetary benefit would likely have increased because, as trees grow, their benefits across all areas increase. For example, a tree with a 76 cm-diameter removes 70 times more pollution per year than does a tree with a 7.5 cm diameter trunk. Around 1.5 tons of CO2 are sequestered from the air & stored for every ton of new wood that grows.
CITYGreen, is another program. CITYGreen analyzes the ecological & economic value of trees in relationship to storm water management, energy conservation, carbon storage & air pollution. This desktop GIS software package requires a tree inventory as well as baseline data for each tree & the area, including impervious surfaces.
GIS-based Trans-Agency Resources for Environmental & Economic Sustainability (T.R.E.E.S.) developed by Treepeople in Los Angles focuses not only on trees, but ecological stormwater management.
There are other urban forest software programs but these 5 give an idea of what is out there. Urban forest computer assessment tools are a relatively recent development. Trees are being recognised as much more valuable than was realized in the past.
City planners & local governments are recognizing the many benefits of the urban forest. This in turn will mean more trees will planted in the right place, looked after & not just planted in poor conditions & left to fend for themselves. It will also mean that biophysical hazards as a result of urbanization, such as air, ground & water pollution, the Urban Heat Island Effect, carbon sequestration & storage & flash flooding will be managed in a sustainable manner.
Instead of trees being seen as just trees or even worse, pests that can be hacked into or removed at a whim, they will finally be recognized as the very valuable resources that they really are. That an increased canopy saves money for Councils will also be recognized & trees will be protected. Hopefully, this will also mean the deliberate increasing of not only the urban forest, but the planting or larger, shade producing trees as a preference, not just small trees that have limited value.