Calculating Form, Function and Value of the Urban Forest i-Tree Calculating Form, Function and Value of the Urban Forest Eric Kuehler Technology Transfer Specialist USDA Forest Service ekuehler@fs.fed.us 706-559-4268 Many people and municipalities look at trees simply as beautiful things that are accessories to the landscape. We plant our crapemyrtles and Bradford pears around town and call it good. When budgets are tight, maintenance dollars for these accessories are the first to be cut. While aesthetic beauty has value, relating that value to city managers can be difficult. A new strategy of relating the benefits and value of urban trees to citizens and/or city managers needs to be developed and conveyed. New tools have been developed that uses current research to calculate those environmental services and place a dollar value on those benefits, so that citizens and elected officials can relate.

Presentation Objectives Describe environmental services from trees Outline available i-Tree tools to calculate those services Display some of the reporting outputs from the i-Tree products and describe how they can be used Demonstrate how some of the tools are being used around the Southeast

What are Environmental Services? Energy Conservation Shade in summer Wind break in winter 5-20% reduction in home energy use Reduced ambient temperature Heat island effect Environmental services are those services that trees provide to us naturally that improve our quality of life.

What are Environmental Services? Stormwater interception Captures rain water Reduced flow rate Help mitigate stormwater problems

What are Environmental Services? Pollution removal Particulate matter Soot Dust Gaseous matter NO2, SO2, O3, CO Carbon Storage

What are Environmental Services? Aesthetic beauty Psychological health Bradford pears and crapemyrtles do provide for emotional, psychological health through their aesthetic beauty, however, that is about all they provide.

i-Tree Suite of public domain urban forest analysis and benefits assessment software PSW – street tree cost/benefit analysis NRS – urban ecosystem benefits model Released to the public in 2006 Quantifies structure, environmental benefits, and monetary value of community trees Helps communities strengthen Urban forest management efforts Advocacy for maintaining its natural resources

i-Tree Suite of Software Tools i-Tree Streets Street tree cost/benefit analysis model i-Tree Storms Pre- / Post-storm debris estimation model i-Tree Vue Urban tree canopy / environmental benefits tool i-Tree Eco Entire urban forest structure, function, value model i-Tree Hydro (not yet released) Stream flow / water quality simulation model For more information and to download software www.itreetools.org

More specifically, what is i-Tree Eco? i-Tree Eco = Urban Forest Effects model (UFORE) Specialized analysis for urban and urbanizing ecosystems Collection of: 1. standardized field methods & 2. model analysis tools Method for establishing permanent plots & collecting data in complex urban areas Combination of research-based mathematical models that quantify urban forest structure, function, and values i-Tree Eco is the interface for the UFORE model; model is operated by the Forest Service with user data i-Tree Eco is the interface for the UFORE model. The model with your data is actually run in Syracuse, NY by the Northern Research Station. The UFORE model is a specialized analysis for urban ecosystems that uses standardized field data collection methodologies for establishing plots and collecting data as well as using mathematical models based on current research to analyze and quantify urban forest structure, function, and values.

What is i-Tree Eco? Complete or sample inventory methodology Complete = inventory all trees in a park, campus, etc. Sample = many 1/10th acre circular plots Entire ecosystem analysis Includes all trees Public & private All land uses Native/exotic Not individual tree management, but we can manage the population (urban forest ecosystem) “Snapshot” of your urban forest i-Tree Eco analyzes and quantifies the entire urban ecosystem, not just the publicly-owned trees that can make up less than 5% of the urban forest. It analyzes trees on public and private property, in all land use classifications (i.e. residential, commercial, industrial, forest, etc.). It even analyses native vs non-native species. UFORE is not designed to be an individual tree management program. It can help you manage the entire urban ecosystem. It gives a snapshot of your urban forest.

What is i-Tree Eco? UFORE calculates for city & land uses Structure, e.g. Tree numbers & cover Species & size distribution Function, e.g. Air pollution removal Total carbon stored & sequestered Effect on building energy use Biogenic emissions Value based on structure, function The UFORE model calculates for each land use strata the structure of the urban forest (i.e. the number of trees by species, their size, canopy cover, etc). From that information, it uses mathematical equations to calculate the urban forest’s function such as carbon and pollution removal, energy use, etc. Based on all of that, it estimates a monetary value that the trees collectively provide to the community.

Overview & Process How does it work? Uses field data to calculate structure from a statistical sample Uses structure data to calculate function Uses function data to calculate value Uses value results to draw conclusions and make management recommendations Everything hinges on the collected field data How and where do we get these data?

To get an accurate picture of your urban forest, you will need to establish 200-250 random plots around the city. The plots can be randomized within land use categories before or after data collection. Obtain the latitude and longitude for each plot center and group the plots together for field crews. Using fine resolution aerial photography (< 1 ft. resolution), create a plot map for each plot to help field crews find plot center.

i-Tree Eco Data Collection General plot information Parcel contact info Reference objects For relocation (QA/QC) Land use % tree/shrub cover % plantable space % ground cover Specific shrub information Species, HT, surface area

i-Tree Eco Data Collection Tree data Species DBH HT Total height Base of live crown Crown width (NS & EW) % dieback and missing Crown light exposure Distance/direction to buildings

i-Tree Eco needs 4 inputs i-Tree users only need to worry about # 1 and 2 Field data Community-specific data Study area Land use strata size Hourly weather data Air quality improvement data (mixing height data) Hourly pollution concentration data # 3 and 4 provided by the UFORE engine

What Results Does i-Tree Eco Provide? 10 charts, 19 tables, and one written report summarizing it all Species composition (by land use type and total city) Size class Condition Species origin (native or non-native) Tree density by land use Importance value of species Air pollution removal and value Carbon storage/sequestration Annual energy savings and avoided carbon Potential pest impacts (ALB, GM, EAB, & DED) Ground cover percentages (impervious vs pervious)

Why i-Tree Eco? What good is it? Aid planning and management Improve forest designs Project future impacts Assess impact of catastrophic events Justify programs Use in conjunction with UTC So, what can the results be used for? They can help you and the planning department plan for and management the entire urban ecosystem and help with forest design. If you have an over-abundance of ash in your community, the Eco analysis can alert you so that you can develop education materials to targeted land use areas and perhaps provide trees for the residents to plant in their yards for the future.

Technology Transfer Specialist i-Tree Eco Overview and Process Questions Comments Discussion Eric Kuehler Technology Transfer Specialist USDA Forest Service ekuehler@fs.fed.us 706-559-4268