Bottom-Up Urban Forest Assessment Tools
Bottom-up approaches use tree inventory and field data to calculate the ecosystem service value of urban forests. Accuracy of bottom-up assessments depends on the sample plot size in relation to the total project area. Consultants typically recommend collecting data from at least 200 one-tenth-acre plots for a standard error of less than 15 percent. The cost of these projects can also vary depending on the size and scope of the project. A typical i-Tree Eco assessment of 200 sample plots could cost up to $40,000 for professional consulting services. Cost drastically drops when students or volunteers collect data rather than highly trained technicians. Bottom-up tools can not only track ecosystem benefits, but they can also help better inform policy or management decisions for urban forests.
- i-Tree Eco (previously known as UFORE) can be used to assess an entire urban forest. It uses sample or complete tree inventory data to calculate the ecosystem service benefits of those trees. Summary reports are generated with detailed information such as air pollution removal, carbon storage capabilities, annual rainfall interception and pest risk analysis. i-Tree Eco is compatible with mobile devices, making data entry available in the field.
BenMAP, from the Environmental Protection Agency (EPA), is integrated in i-Tree ECO. It is a computer program that uses geographic information system (GIS) data to estimate economic and health implications of urban forests based on air quality. When changes in air quality occur, BenMAP is able to calculate the changes to economic and health factors. This program can be useful for policy analysts, decision makers and urban ecologists.
- i-Tree Streets (previously known as Stratum) is limited to assessing street tree population benefits. Users can use a sample or existing street tree inventory to analyze a specific area. Summary reports are generated with detailed information such as stormwater control, property value increase and air quality improvement.