Chapter 6. Tree Inventory and the Tree Inspection Cycle

Tree Inventory and the Tree Inspection Cycle

The foundation of an effective urban forest management program is a detailed tree inventory. A tree inventory provides information such as tree health, species, size and location; this information is used to generate reports that can help urban foresters in their strategic planning, such as the development of maintenance plans and management plans, as well as to help educate residents about their urban forest. Inventory data can be used to identify species diversity and distribution, percentage of canopy cover, size/class distribution, and other data.

There are different types of tree inventories: some catalogue only a sample of trees, which can be extrapolated to represent the entire urban forest; others inventory only diseased or hazardous trees; while others inventory every individual tree in the urban forest. Some inventories use aerial photography or GIS to conduct an inventory of tree cover type. Citizens and non-profit organizations can participate in the development of tree inventories.

Coupled with an inventory, a tree inspection cycle is integral for proper tree maintenance and hazard abatement. Effective tree monitoring enables park managers, urban foresters, and planners to evaluate the urban forest resource and develop short and long-term initiatives, which can in turn provide substantial cost savings and mitigate safety issues.

Canadian online resources:

• Bardekjian, A. (2004). A tree inventory management plan for the Toronto District School Board. Major Paper for the Master of Forest Conservation Program. Commissioned by the Toronto District School Board.
• BCIT Forestry: Big Tree Inventory: Lower Seymour Conservation Reserve (LSCR), North Vancouver, BC
• City of Charlottetown: Street and Park Tree Inventory

Non-Canadian online resources:

• International Society of Arboriculture: Managing Hazards and Risks
• University of Connecticut: The Tree Inventory
• USDA Forest Service: Urban Tree Risk Management: A Community Guide to Program Design and Implementation 

Further reading:

Nielsen, A. B., Östberg, J., & Delshammar, T. (2014). Review of Urban Tree Inventory Methods Used to Collect Data at Single-Tree Level. Arboriculture & Urban Forestry, 40(2), 96-111. Retrieved from https://www.researchgate.net/profile/Anders_Nielsen5/publication/286000702_Review_of_urban_tree_inventory_methods_used_to_collect_data_at_single-tree_level/links/569775ec08ae34f3cf1ec1e3/Review-of-urban-tree-inventory-methods-used-to-collect-data-at-single-tree-level.pdf

Roman, L. A., Scharenbroch, B. C., Östberg, J. P. A., Mueller, L. S., Henning, J. G., Koeser, A. K., Sanders, J. R., Betz, D. R., & Jordanj, R. C. (2017). Data quality in citizen science urban tree inventories. Urban Forestry & Urban Greening, 22, 124-135.  https://doi.org/10.1016/j.ufug.2017.02.001

Roman, L. A., Battles, J. J., & McBride, J. R. (2016). Urban tree mortality: a primer on demographic approaches. Urban tree mortality: a primer on demographic approaches. USDA Forest Service, General Technical Report NRS-158. Retrieved from https://www.fs.usda.gov/nrs/pubs/gtr/gtr_nrs158.pdf

Tuhkanen, E.-M., Männistö, A., Terho, M., Raisio, J., Arrakoski, K., Mänttäri, M., Riikonen, A., Tanhuanpää, T., Linden, L., & Verkasalo, E. (2018). Using city tree inventory data as a tool of planning, management and economic valuation of ecosystem services provided by urban trees.  Abstracts : European forum on urban forestry 2018. Retrieved from https://docs.wixstatic.com/ugd/fb678c_092c45856a1a48839ecf1820a68ed1ed.pdf