Street Tree Inventory Report Foster-Powell Neighborhood November 2014 Street Tree Inventory Report: Foster-Powell Neighborhood November 2014 Written by: Kat Davidson, Angie DiSalvo, Jen Gorski, Jeremy Grotbo, Lele Kimball and Jeff Ramsey Portland Parks & Recreation Urban Forestry 503-823-4484 [email protected] http://portlandoregon.gov/parks/treeinventory Foster-Powell Tree Inventory Organizers: Kate Carone, Karl MacNair, Meg McHutchison, Joseph Schlechter and Rick Till Staff Neighborhood Coordinator: Jen Gorski and Lele Kimball Data Collection Volunteers: Li Alligood, Naomi Bishop, Ben Brady, Jonathan Brandt, Jenn Brenner, Dylan Carlson, Kate Carone, Alayna Cato, Amie Chapman, Deidre Charlton, Katie Charlton, Angela Cortal, Kat Davidson, Jenai Fitzpatrick, Lise Gervais, Meara Gordanier, Sandra Johnson, Jennifer Karps, James Keiter, Sean Kelly, Steve Larson, Natasha Lipai, Virgil Llewellyn, Amy Lodholz, Sochetra Ly, Zosia Lynch, Jeffrey Lynott, Jan Maas, Jonathan Maas, Karl MacNair, Susie MacPherson, Meg McHutchison, Megan Meek, Taylor Meek, Louis Miles, Matthew Nenninger, Victoria Oglesbee, Erika Palmer-Wilson, Nick Panaras, Nathalie Paravicini, Jed Roberts, Joseph Schlechter, Paige Schlupp, Tina Serrano, Lori Snow, Betsy Tighe, Rick Till and Greg Weston Data Entry Volunteers: Sachi Arakawa, Jason Berney, Alayna Cato, Peter Del Zotto, Nikhilesh Desai, Cecily Douglas, Mike Ellis, Erin Etchison, John Frewing, Zeph Friedman-Sowder, Lise Gervais, Dan Grilli, Lauren Kael, Patrick Key, Jerek Laursen, Christopher Lewis, Edelina Naydenova, Kathryn Strang, Jayme Taylor, Megan Van de Mark, Madison Weakley and Giovanna Zivny Arborist-on-Call Volunteers: Fred Nilsen, Jim Sjulin and Ruth Williams GIS Technical Support: Josh Darling, Portland Parks & Recreation Financial Support: Portland Parks & Recreation ver. 11/1/2014 Portland Parks & Recreation 1120 SW Fifth Avenue, Suite 1302 Portland, Oregon 97204 (503) 823-PLAY Commissioner Amanda Fritz www.PortlandParks.org Director Mike Abbaté Table of Contents Key Findings .......................................... 1 About Portland’s Street Tree Inventory . 3 The importance of street trees ......................... 3 The inventory process................................ 3 Foster-Powell Street Tree Inventory ....................... 5 Neighborhood Characteristics ......................... 5 Urban Forest Composition............................ 6 Species diversity and tree type composition . 6 Functional tree type .............................. 8 Size class distribution ............................. 9 Mature tree form distribution ..................... 10 Importance value................................ 10 Tree Condition .................................... 11 Planting Site Composition and Stocking Level ........... 12 Planting sites................................... 13 Stocking level .................................. 13 Right tree in the right place ....................... 14 Replacement Value ................................. 15 Environmental and Aesthetic Benefits .................. 16 Recommendations ..................................... 19 Next Steps ........................................... 21 References ........................................... 23 Appendices........................................... 25 A: Methods ....................................... 25 B: Street trees of Foster-Powell by tree type ............. 27 C: Street trees of Foster-Powell by size (map) ............ 30 D: Young street trees (trees ≤ 3” DBH) (map) ............ 31 E: Large street trees (trees > 24” DBH) (map) ............ 32 F: Poor and dead street trees (map) .................... 33 G: Planting site types (map) .......................... 34 H: Planting site sizes (map)........................... 35 I: Available street tree planting spaces (map) ............. 36 J: Priority street tree planting spaces (map) .............. 37 Portland Parks & Recreation i Volunteers, guided by Portland Parks & Recreation Urban Forestry staff, collected data on all 2,325 street trees within Foster-Powell neighborhood to compile the neighborhood’s first complete street tree inventory. The data are being used to inform the creation of a Neighborhood Tree Plan to guide volunteers in caring for their community’s trees. ii Street Tree Inventory Report – Foster-Powell Neighborhood 2014 Key Findings This report provides the results of a street tree inventory conducted in Foster-Powell neighborhood in 2014, along with Portland Parks & Recreation (PP&R) Urban Forestry staff recommendations for the Foster- Powell tree team. Over the course of four work days, 50 volunteers contributed 276 hours collecting data on each of the neighborhood’s 2,325 street trees. URBAN FOREST STRUCTURE • Foster-Powell’s street trees are dominated by linden, crabapple, plum, and maple and does not meet recommended species diversity guidelines. While 87 tree types were found in this inventory, only two families, Rosaceae and Sapindaceae, account for more than 50% of the resource leaving Foster-Powell’s street tree population vulnerable to pests, pathogens, and a changing climate. The dominance of broadleaf deciduous trees found in this inventory points to a need to diversify functional, as well as genetic diversity in order to maximize value and create a more resilient, sustainable urban forest. • Young trees are overrepresented in Foster-Powell. This is likely the result of successful tree planting efforts in recent years and provides an opportunity for inexpensive young tree maintenance activities that will reduce future costs and ensure the longevity of these trees. If young trees are properly cared for today, Foster-Powell will have a healthier age distribution of street trees in the future. • Large form trees are necessary to increase canopy cover and the benefits they provide for Foster-Powell’s residents. Only 20% of Foster-Powell’s street trees are large form species. Planting the estimated 117 large available spaces will help maximize tree canopy in Foster-Powell's rights-of- way. PLANTING SITES AND STOCKING LEVEL • The predominance of small planting sites in Foster-Powell poses a challenge to the growth and longevity of street trees. Small sites represent 51% of planting spaces in the neighborhood. While it is important to plant all available spaces, in some areas this may not be enough to equitably distribute canopy in Foster-Powell. Creative expansion of planting sites or increased planting on private property may be the only ways to meet canopy goals. • Street tree stocking level in Foster-Powell is 39%. Planting efforts should focus on the largest sites with no overhead high voltage wires first, as large form trees will provide the most long-term benefits to the neighborhood. URBAN FOREST VALUE AND BENEFITS • Foster-Powell’s street trees produce approximately $133,000 annually in environmental and aesthetic benefits. The calculated replacement value of this resource is $4.8 million. Planting efforts focused on appropriately sized trees distributed across the neighborhood will ensure that future benefits are equitably distributed among all residents. Portland Parks & Recreation 1 Clockwise from top left: 1) Paperbark maple (Acer griseum) planted in a large site, highlighting a missed opportunity for a larger form specimen. 2) A typical small planting strip with young trees. 3) The largest diameter right-of-way tree in Foster-Powell neighborhood is a Douglas- fir (Pseudotsuga menziesii) in the Firland Parkway on SE 72nd Avenue. 4) Foster-Powell’s low stocking level means that there are still a lot of places to plant trees. 2 Street Tree Inventory Report – Foster-Powell Neighborhood 2014 About Portland’s Street Tree Inventory THE IMPORTANCE OF STREET TREES Street trees are an important public asset in urban environments, serving as a buffer between our transportation corridors and our homes while enhancing the livability of our city. As integral components of a community’s green infrastructure, street trees provide multiple economic, environmental, and social benefits such as cleaner air and water, cooler summer temperatures, safer streets, and increased property values. Unlike traditional, “grey” infrastructure, which begins to deteriorate the moment it is installed, the benefits that street trees provide increase over the lifetime of the tree, making their planting and maintenance one of the best investments a city and its residents can make. While street trees are only one component of Portland’s urban forest, they are particularly important because they are the trees that residents Urban forests are complex, living interact with most. Having adequate information resources that interact both about the street tree population allows a community to make informed decisions about species selection, positively and negatively with the planting, and maintenance priorities. Information on surrounding environment. They the location, condition, and diversity of the street tree produce multiple benefits and have population enables our communities to steward this resource and ensure its continued benefits into the associated management costs. In order future. Undertaking a street tree inventory is not only to fully realize the benefits, a sound an investment in the current and future well-being of the trees, but in the community itself. understanding of the urban forest THE INVENTORY PROCESS resource is needed. This understanding Portland’s Tree Inventory Project began with a pilot starts at the most basic level with a street tree inventory