B21B-0263: i-Tree: tools to assess and manage structure, function, and value of community forests

Trees in urban communities can mitigate many adverse effects associated with anthropogenic activities and climate change (e.g. urban heat island, greenhouse gas, air pollution, and floods). To protect environmental and human health, managers need to make informed decisions based on model results about urban forest management practices. However, it is difficult for them to get the appropriate model results due to obstacles such as difficulties in preparing inputs, limited access to needed models, and unsuitable outputs or user interfaces. Here we introduce the i-Tree models developed through a consortium of partners including USDA Forest Service, Davey Tree Expert Company, National Arbor Day Foundation, Society of Municipal Arborists, International Society of Arboriculture, and Casey Trees, which helps communities of all sizes strengthen urban forest management and advocacy efforts by quantifying the structure of community trees and the environmental services that trees provide. i-Tree is in the public domain and freely available for download or use through the i-Tree web site (www.itreetols.org).

i-Tree software suite is composed of 11 components, i-Tree Eco, Streets, Hydro, Vue, Species, Storm, Pests, Design, Canopy, Landscape, and Forecast. Each of the components was developed based on state-of-the-art, peer-reviewed models and techniques developed by the USDA Forest Service. For instance, i-Tree Eco is an adaptation of the Urban Forest Effects (UFORE) model and i-Tree Streets implements the STRATUM model. These models will be combined into one tool in a future version. i-Tree Design and Vue utilize the results produced by these models.

All tools work with a server-client architecture (web server - web client or Windows server - Windows client) and most of the national standard data are stored in the server, which provides users an easy access to the input data of the models. Analyses can be performed at various scales, i-Tree Design works for individual trees (points), i-Tree Streets for street trees (lines), and i-Tree Eco, Vue, and Canopy for any sized area. To enhance the user-friendliness of the tools, Windows-based or web-based Graphical User Interface (GUI) is provided. While most i-Tree applications employ a spatially lumped approach, i-Tree landscape employs a spatially distributed approach that allows users to map changes in canopy cover and ecosystem services through time and space. These new i-Tree tools will provide an advanced platform for urban managers to assess the impact of current and future urban forests.

Input:

Function:

Output:

Nationwide data for the US are stored in a server and retrieved by a user’s computer at run-time. These data include US Forest Service’s location-related parameters, NOAA’s Integrated Surface Hourly (ISH) (www7.ncdc.noaa.gov/CDO/cdo) and radiosonde (www.esrl.noaa.gov/raobs/) data, USGS’s streamflow data (waterdata.usgs.gov/usa/nwis/sw), and US EPA’s Air Quality System (AQS) data (www.epa.gov/ttn/airs/airsaqs/detaildata/downloadaqsdata.htm). Nationwide remote-sensed images (e.g. NLCD and Google Maps) are also employed to estimate tree canopy characteristics. i-Tree Design allows users to input tree data on Google Maps, and i-Tree Vue allows users to import tree cover maps from NLCD. i-Tree Eco and Streets use field survey data of community tree and street tree populations, respectively.

Output data in several forms (texts, tables, charts and automatically created report) can be accessed via client side application.

Two major functions of i-Tree are 1) to analyze current forest structure (e.g., species composition, number of trees), and 2) to estimate the environmental benefits provided by the trees (e.g., carbon storage and sequestration, energy conservation, air pollution removal, and storm water reduction). The forest structure needs to be first identified with i-Tree Design, i-Tree Streets, i-Tree Vue or Eco depending on forest types, then ecosystem services and values can be estimated with common models and protocols i-Tree Canopy allows users to estimate tree cover using Google Maps. i-Tree Hydro estimates tree and impervious cover effects on stream flow and water quality within a watershed. Two more i-Tree applications, i-Tree Forecast and i-Tree Landscape are now under development i-Tree Forecast simulates forest structure and services through time based on planting, growth and mortality rates. i-Tree Landscape employs a spatially distributed approach that allows users to map changes in canopy cover and ecosystem services through time and space.

Lumped DistributedSpatial Scheme

Web GISSystem Architecture

Point

Line

Area

Forest

Watershed

Analysis Domain Canopy

Design

Windows Client/Server

Species

Species

Vue Eco

Streets Pest

Pest

Storm

Storm

Hydro

Hydro

Landscape

Landscape

Introduction Tools Background & Composition

System Overview

Forest TopologyField Survey Google Map

LandcoverTopography

WeatherAir Quality

Streamflow

Point Line Area

Air Pollution Carbon Temperature

Stormwater Energy

OutputFunctionInput

Air

EnergyWater

Present Future

Timeline

Pest Storm SpeciesTree Damage

Table

Chart

Report

Web

Other

Tree Species

Estimate Ecosystem

ServicesDefine Canopy Structure

Forecast

• Uses Google maps• Individual tree benefits:

Air pollutants removed

CO2 removedEnergy savedStormwater reduced

Storm

• Estimates street tree damages caused by a storm

Hydro

• Estimates water quantity/quality within a watershed

Pest

• Additional function of i-Tree Streets

• Estimates potential risk to various pests and health symptoms related to various pests

• Uses field survey data• Street trees benefits:

Air pollutants removed

CO2 removedEnergy savedStormwater reducedAesthetic

Landscape

• NLCD and Google maps• Urban forest benefits:

Air pollutants removed

CO2 removedEnergy savedStormwater reduced

• Photo-interpret Google aerial images

• Estimates tree and other cover types in the image

• Uses field survey data• Urban forest benefits:

Air pollutants removed

CO2 removedEnergy savedStormwater reduced

• Under development• Spatially estimates

canopy structure and ecosystem services across a region.

• Under development• Integrated within other i-

Tree applications• Simulates canopy

structure through time

Species

• Selects appropriate tree species to plant based on environmental functions and geographic areaAesthetic

System Diagram

Design

Satoshi Hirabayashi1, David Nowak2, Scott Maco1, Theodore Endreny3 and Chuck Kroll3

1 The Davey Institute, The Davey Tree Expert Company, Syracuse, NY, United States2 Northern Research Station, U.S. Department of Agriculture, Forest Service, Syracuse, NY, United States

3 Department of Environmental Resources Engineering, SUNY ESF, Syracuse, NY, United States

i-Tree tools are in the public domain and are freely available by registering at www.itreetols.org. Visit this web site for more information such as:

• News

• Manuals & workbooks

• Trainings & seminars

• Model descriptions & publications

• Presentations & reports

• Support

• User forums

i-Tree Design links to Google maps and allows users to sketch their home and see how the trees around their home affect storm water reduction, energy use and savings, air quality improvements, and CO2 reduction. Users can use this tool to assess which locations and tree species will provide the highest level of benefits. This is a simple tool geared toward homeowners, school children or anyone interested in tree benefits..

Canopy Streets

i-Tree Canopy is a tool that allows users to easily photo-interpret Google aerial images to produce statistical estimates of tree and other cover types along with calculations of the uncertainty of their estimates. This tool provides a simple, quick and inexpensive means for cities and forest managers to accurately estimate their tree and other cover types. i-Tree Canopy can be used anywhere in the world where high-resolution, cloud-free Google images exist.Storm SpeciesPest

Vue Eco Hydro

i-Tree Streets is similar to Eco, but focuses on street tree populations using reference city street tree data. It includes additional estimates of storm water impacts, property value effects and cost-benefit analyses.

The Pest Detection Protocol provides a systematic protocol for long-term pest detection and monitoring. It allows users to input health signs and symptoms of their trees to produce indications of potential pests, diseases and threats to their forest. The protocol is incorporated within i-Tree Streets and will be in Eco soon.

i-Tree Storm helps assess street tree damage in a simple and efficient manner immediately after a severe storm. It is adaptable to various community types and sizes and provides information on the time and funds needed to mitigate storm damage.

i-Tree Species Selector is a free-standing utility designed to help users select the most appropriate tree species based on desired environmental functions and geographic area.

i-Tree Vue allows users to utilize freely available National Land Cover Data (NLCD) maps to assess their community’s land cover, tree canopy and impervious cover. To overcome an underestimation of tree cover in NLCD maps, users can produce adjusted cover maps and superimpose transparent national cover maps (30 m resolution) on top of Google aerial images. The program also quantifies and maps spaces available for planting and broadly estimates some ecosystem services provided by the current trees and forests. The effects of changes in tree cover on future benefits can also be illustrated.

i-Tree Eco uses sample or inventory data to assess forest structure, ecosystem services and values for any tree population (including number of trees, diameter distribution, species diversity, potential pest risk, air pollution removal, carbon storage and sequestration, VOC emissions, and building energy effects). It runs on local field data and hourly meteorological and pollution data. The program includes plot selection programs, data entry programs or PDA data entry, table and graphic reporting and exporting, and automatic report generation.

i-Tree Hydro is a program designed to simulate the effects of changes in tree and impervious cover within a watershed on hourly stream flow and water quality. It contains auto-calibration routines to help match model estimates with measured hourly stream flow and produces tables and graphs of changes in flow and water quality due to changes in tree and impervious cover within the watershed.

Requests for i-Tree Tools has grown at an average rate of approximately 25% per year since launching in 2006. i-Tree has been downloaded by over 8,700 users in over 100 countries across the globe.

Share & Support User Base

Tool Usage

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Requests for i-Tree Tools (Cumulative)

Other Countries

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