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Parks & Recreation

Healthy Parks, Healthy Portland

Phone: 503-823-PLAY (7529)

Fax: 503-823-6007

1120 SW Fifth Ave., Suite 1302, Portland, OR 97204

Portland Parks & Recreation Urban Forestry News and Activities 

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Dutch Elm Disease Update

by Kasey M. Yturralde, Botanic Specialist II

Proportion of elm inventory by property type (N=4767 elms)

Portland Elms

PP&R Urban Forestry has a new tool in their elm management arsenal, data. This summer, with the help of 1400 tree inventory volunteers (and about 17,000 volunteer hours), Urban Forestry (UF) completed an inventory of Portland’s street trees, which included elms. UF staff inventoried private elms as well, resulting in the first complete assessment of Portland’s elm population to date. This inventory data is critical in managing elms, which are in a constant battle with Dutch elm disease and meeting the challenges of living in an urban environment.

Dutch elm disease (DED) is caused by a fungus (Ophiostoma spp.), which spreads via adjacent elm roots and may also be transmitted by bark beetles. DED may spread by roots, in a process called root grafting. Root grafting may occur when DED positive elms are in close proximity to other elms and there is contact between roots below ground. DED spores are also spread via an insect vector, elm bark beetles. Understanding where elms are located across the city and where elm mortality occurs is a first step to understanding how DED spreads through Portland’s elm population.

Elms and Dutch elm disease management

Fortunately, there is a treatment used to prevent the growth of the DED fungus. The treatment consists of a special fungicide that is injected at the base of elms, into their water-conducting system, or xylem. Healthy elms that are good candidates for treatment are treated every three years. The tree itself also helps propel the protective fungicide up the tree, throughout the canopy. In 2016, UF treated 129 park elms with the Arbotect fungicide. Neighborhood groups, such as Save Our Elms, also joined the effort and treated 115 elms with either Arbotect or Alamo.

Figure 1. Neighborhood elm inoculation by microinjection.

Elm loss

In 2016, 55 elms (approximately 1% of our elm population) tested positive for DED and were removed- of these, Urban Forestry removed 45 out of the 55 (82%).  Most of the Urban Forestry removals (29 out of 45) were in the public right-of-way (ROW).

Analysis of elm loss reveals interesting spatial patterns. In some areas with high elm density, such as Ladd’s Addition, adjacent elms are lost in each subsequent year as DED progresses down a block, likely via root grafting (see Figure 2).

Figure 2. Map of elm trees in Ladd’s Addition. The light green buffer around elms shows the 25-foot distance within which DED can be transmitted via root grafting. DED can spread up to a distance of 50-feet.

However, in other areas of high density, the pattern of annual loss may not occur via root grafting, or may occur in combination with transmission via elm bark beetles. For example, in Eastmoreland there isn’t a clear spatial progression of elm loss along blocks (Figure 3). However, there are other potential factors that could explain the differences between elm loss in the two neighborhoods. For example, the neighborhoods differ in their use of fungicide used to prevent growth of DED.

Figure 3. Map of elm trees in Eastmoreland neighborhood.


Currently, Urban Forestry removes DED-infected elms in the public ROW, which requires a full crew of arborists and lasts an average of three days per tree, not including stump removal. This service, however, is not offered to residents for the removal of other tree species located in the ROW. In the interest of equity, Urban Forestry recommends that removal of DED-infected elms becomes the responsibility of the adjacent homeowner. This change in policy would then comply with the Title 11 Tree code, which requires adjacent homeowners to maintain and remove street trees. In addition, this change would lead to more equitably distributed city services as Urban Forestry would then dedicate more time to maintenance and care of park trees across the city, as well as continuing to monitor elms for DED.

Given potential changes in the removal policy of DED-infected elms, Urban Forestry could reallocate time and effort to DED prevention. For example, patterns of DED-related elm loss seem to indicate that the mode of DED transmission may vary across Portland. Formally investigating the spread of DED through Portland’s elms could help inform future management decisions.

Portland also manages for DED through the planting of DED-resistant cultivars. The size distribution of such elms is heavily skewed toward smaller elms (Figure 4). Proper tree pruning will be critical to ensuring a healthy future for these young elms. As neighborhood groups continue their care of elms, they may want to incorporate young-tree pruning in their elm management, of course with the proper tree pruning permits.  

Figure 4. Size class distribution of DED-resistant elms (DBH-diameter of tree at 4.5 feet high)

Currently a moratorium on elm pruning is implemented from April 15th through October 15th, to avoid pruning when elm bark beetles are most active, as elms with injuries, such as those made by pruning, are especially attractive to elm bark beetles. To further prevent DED, Urban Forestry is considering adjusting the moratorium window each year, dependent on springtime temperatures, which predict onset of beetle activity.

For more information on Dutch elm disease:

How to Identify and Manage Dutch Elm Disease

Dutch elm disease

Fungicide Injection to Control Dutch Elm Disease: Understanding the Options



Pruning Workshop with the Hillsdale Tree Team

Portland Parks & Recreation Urban Forestry and the Hillsdale Tree Team are partnering to offer this street tree pruning workshop to care for young street trees in the neighborhood.

By Mason Wordell, Urban Forestry Tree Plan Coordinator and AmeriCorps Member

Join Urban Forestry and the Hillsdale Tree Team
for a pruning workshop and work party!

When: 8:45 am - 12:00 pm, April 29, 2017
Where:  Rieke Elementary School | 1405 SW Vermont St.

Click here to register!

8:45 – 9:00 am – Sign-in, coffee & snacks
9:00 – 9:30 am – Pruning Demonstration
9:30 – 11:45 am – Pruning neighborhood trees in small groups
11:45 – 12:00pm – Return and wrap up

Portland Parks & Recreation Urban Forestry and the Hillsdale Tree Team are partnering to offer this street tree pruning workshop to care for young street trees in the neighborhood. The Hillsdale Tree Team is in their first year of tree stewardship, and this is their first pruning workshop in the neighborhood.  In Hillsdale, small trees between 0" and 6” dbh (diameter at breast height) account for 37.9% of the street trees. Clearly, there is a high need to care for these young, small trees as they mature and grow. One important aspect of tree maintenance is structural pruning.

Pruning is an important part of tree care and maintenance, and everyone is welcome to participate in this workshop to learn more about how they can actively care for their trees.  Knowing when to prune and what to look for can help you make successful cuts that will help cultivate beautiful, structurally sound, and long living trees.  Read our previous blog post to learn more about pruning! View the City’s official pruning standards here.  

Meet us on April 29th at Rieke Elementary School, near the main parking lot! We will be out rain or shine -  we recommend long pants and long sleeves, sturdy shoes and a rain/sunhat and bring a backpack, rain gear and water bottle. Instruction, tools, gloves, coffee, water and snacks will be provided.

For more information, or if you have something you want to talk about, contact:
Mason Wordell
Tree Plan Coordinator and AmeriCorps member
(503) 201-3133

Certified Arborists can receive 3 hours of ISA CEUs for participating and leading small groups. Contact Mason for details!


Trees, People, and History in the Kerns Neighborhood

Join Portland historian Dave Hedberg, Urban Forestry, and the Kerns Tree Team for a History Think & Drink! Learn about Trees, People, and History in the Kerns Neighborhood!

By Dave Hedberg, Urban Forestry Community Service Aide II

Join Portland historian Dave Hedberg, Urban Forestry, and the
Kerns Tree Team for a History Think & Drink!

When: 6:30 pm - 8:30 pm on Tuesday, April 11th, 2017
Location: The Zipper | 2705 NE Sandy Blvd.

Register Here! 

William Kerns, East Mount Tabor’s emigrant homesteader had serious skills with the broad axe. In the 1850s, Kerns cleared his 320-acre Donation Land Claim making mainly wood shingles and shakes for sale. According to a descendant, Kerns could “hew a sill or a beam with the greatest precision and with amazing speed.” In 1855, the East Portland-Mount Tabor School District elected Kerns as their school director. He led the movement to buy land for Washington High School, and later, the board named the school at NE 25th and Everett after Kerns

Image from: Genealogical Narrative: a history of three pioneer families, the Kerns, Popes, and Gibsons by Edith Kerns Chambers

The Kerns Neighborhood gets its name from the school, and by association, with William Kerns. It’s easy to imagine Kerns, axe in hand, hungry for timber, as he made east Portland’s own Stumptown. We should be careful, though, to judge. After all, his was a practice common for the time, and he was not alone in thinking this was improving the land. What is more fascinating is the story of the neighborhood after. 

Map of Trees by size in Kerns. You can clearly see where the canopy is lacking on Sandy Boulevard.

Following William Kerns’ days with his axe, people replanted as they made the Kerns Neighborhood their home. According to the 2014 Kerns Neighborhood Street Tree Inventory, the neighborhood has 3,140 trees representing 91 different types. There’s actually a good number of large trees throughout the neighborhood (25%). However, it’s easy to see on the map where canopy is lacking. Look no further than Sandy Boulevard. This bustling commercial district bisects the neighborhood diagonally in a northeast-southwest direction. The history of this road is the key to understanding why it lacks mature trees.

Sandy Road on an 1851 GLO Map.

The Sandy Road, as it once was called, is one of the city’s oldest roads. This 1851 Government Land Office map shows the road running nearly the same path as it does today. For emigrants who floated the Columbia River George, Sandy was the final road into Portland and the Willamette Valley. By the turn of the century, Sandy Road was a commercial district and arterial into downtown for farmers and the increasing numbers of suburban home and apartment dwellers in the city. 

Sandy Blvd looking northeast from NE 24th Ave, 1932. City of Portland Archives, A2012-006.

In the 1920s, residents along Sandy Road debated changing the name to Roseway Boulevard. Interested in beautifying the road after the Rose Festival, advocates modeled the idea after the great European boulevards. Envisioning “roses, trees, and shrubs… it will be a real boulevard and surely be entitled to that dignified name,” declared the Portland Men’s Community Club.  Instead, the name changed to Sandy Boulevard to honor the local significance of the road to pioneers like Mr. Kerns. Still, advocates hoped for the large trees to line Sandy Boulevard, which had ample setbacks.

Sandy Blvd looking east toward NE 20th Ave, 1940. City of Portland Archives, A2005-001.

By the 1930s Sandy road was widened for increasing auto traffic, occupying the space for large trees envisioned a decade earlier. This shot of Sandy Boulevard from 1940, if it weren’t for the cars, looks similar to today. With a history as a county road, a city boulevard, and a state highway, the growth of Sandy Boulevard has hardly left any room for street trees. Still today, there are possibilities to bring more trees to Sandy today and care for the many trees planted after pioneers like William Kerns cleared the land.

NE Sandy Blvd and NE 28th (where the Zipper is today), 1937. City of Portland Archives A2005-001.

If you want to learn more about how human history and the urban forest are inextricably connected, please come for a free presentation at the Zipper, Tuesday night April 11, 2017 from 6:30 – 8:30. We’ll not only learn about the past, but we will discuss simple ways to be stewards of our urban forest. Register Here! 

For more information, or if you have something you want to talk about, contact:
Mason Wordell
Tree Plan Coordinator & AmeriCorps Member

The Arboreal Legacy of the Albina Neighborhood Improvement Project

By Dave Hedberg, Urban Forestry Community Service Aide II

"You are the key to improving your neighborhood."
---Albina Neighborhood Improvement Project, 1962

Albina Neighborhood Improvement Project Block Leaders, March 1964. City of Portland Archives, A2010-003.2405.

Join Dave Hedberg, Urban Forestry, and the Humboldt Tree Team for a Walk & Talk
on the Arboreal Legacy of the Albina Neighborhood Improvement Project

When: 9:00 - 11:00 am on Saturday April 1, 2017
Where: UNITE Oregon |  700 N Killingsworth St, Portland, OR 97217

Register Here! 

Often, history fails to recognize the significant contributions of seemingly average citizens. However, every day you see plenty of artifacts that represent the work of dedicated citizens—Portland’s 218,000 street trees are excellent examples. In 1961, a self-organized group of Albina area residents made a lasting mark in their neighborhood when they created an organized and well-planned tree planting program.  This small group of citizens gave birth to the Neighborhood Tree Team and inspired generations of citizen leaders in Portland's urban forest. Their work, which many of us continue, should not be forgotten.

Albina Neighborhood Improvement Program, March 1964. Note the Tree Program on the board. City of Portland Archives, A2010-003.2388.

Concern for trees was only a small part of the overall Albina Neighborhood Improvement Project (ANIP). In the 1960s, the Albina neighborhood was suffering from a serious lack of city investments, poverty, and lack of green spaces. Urban renewal projects, like Memorial Coliseum and Legacy Emanuel Hospital, had displaced citizens in the African American community. Prejudicial lending not only limited African Americans to buying homes in the Albina area, but also restricted their access to credit for home loans, repairs, and even business loans. Albina residents worried that their neighborhood was next for demolition.

The grass-roots Albina Neighborhood Improvement Program started addressing the decades of disinvestment. Led by the Reverend Cortlandt Cambric of Hughes Memorial Methodist Church and co-chaired by Reverend T.X. Graham of the Portland First AME Zion Church and Father Mell Stead of Immaculate Heart Catholic Church, ANIP secured federal funding for much-needed improvements like neighborhood streetlights, street trees, sidewalks, general home maintenance, alleyway cleaning, and the creation of DeNorval Unthank Park. Dozens of Block Group Leaders managed the various projects while even more volunteers took to action by helping their neighbors cleanup and beautify Albina.

Albina Neighborhood Improvement Project planted over 500 flowering cherries in March 1964, especially along N Kerby and N Height streets. City of Portland Archives, A2010-003.2402.

In 1962, the ANIP Tree Program Sub-Committee, consisting of the Rev. F. J. Crear, Mrs. Robert Kutch, Mr. Herbert Lewis, and Mr. E. H. Thiel, designed and led an innovative tree removal and replacement program. Applying for their own funding, the program removed large-form trees from the small, narrow 3.5 ft. planting strips. They replaced these trees with a mix of Incense Cedar, Japanese maple, Dogwoods, Birch, and mostly Kwanzan flowering cherry. They secured support from Portland General Electric and Logger Jacks Tree Service for the stump grinding and auguring for the new cherries, which nursery owner Glen Handy supplied from Boring, Oregon. You can still see many of the spectacular flowing cherries when they bloom every spring. 

In 1964, the Albina Neighborhood Improvement Project’s flowering cherries came from Glen Handy’s nursery in Boring, Oregon. City of Portland Archives, A2010-003.2397.

The program, which also included pruning work parties, was so successful that it grew over the years, expanding the number of trees pruned, removed, and replanted to over 500 in 1964 alone! Other neighborhoods like Woodlawn, Humboldt, King, and Irvington were inspired by ANIP’s Tree Committee and began forming their own tree planting programs with funding from the federal Model Cities Program. These 1960s and 1970s citizen-led plantings, in part, inspired the creation of the Urban Forestry Commission and Urban Forestry. 

An Albina Neighborhood Improvement Project street tree pruning, December 1961. City of Portland Archives, A2010-003.2304.

With dozens of Neighborhood Tree Teams working as stewards of the Urban Forest today, many have forgotten the historical legacy of the extra ordinary Albina Neighborhood Improvement Project. In essence, you can see ANIP’s legacy across the city. As you walk down the street enjoying our urban forest, remember that these trees are artifacts of citizens like yourself! 

Albina Neighborhood Improvement Project tree planting January 1963. City of Portland Archives A2010-003.2364.

Want to know more? Or, do you have a story about tree plantings in the greater Albina area? Please consider sharing it with us! Register for the free upcoming Tree History in the Humboldt Neighborhood on April 1. We will share stories, explore the past and present efforts for beautification in the neighborhood, and take a short walk to see some historic trees. 

Register Here!

For more information, or if you have something you want to talk about, contact:
Mason Wordell
Tree Plan Coordinator & AmeriCorps Member


Planting Advisory Committee Members Needed - Apply by April 23, 2017

 Help us Plant the Future of Portland

Tree canopy in Portland is not equitably distributed throughout the city: lower income neighborhoods have significantly lower tree canopy coverage and fewer street trees than other neighborhoods. As the responsible bureau for the management and regulation of trees, Portland Parks & Recreation (PP&R) Urban Forestry is mandated to maximize the benefits of the urban forest for all Portland residents (Urban Forest Management Plan 2004). PP&R Urban Forestry has been tasked to create a Citywide Tree Planting Strategy to guide efforts of expanding the urban tree canopy, with a strong focus on equity. PP&R Urban Forestry will be partnering with community members, stakeholders of targeted neighborhoods, and Portland State University to identify barriers for tree planting in low canopy areas and provide recommendations on how to gain community support for tree planting. 

The Citywide Tree Planting Strategy Advisory Committee will provide input to Portland Parks & Recreation on tree planting strategy recommendations made by Portland State University. The committee will meet five times from June through October 2017 and will assist with the following:

  • Reviewing City bureau and public agency priorities around tree planting
  • Reviewing a prioritization data tool for selecting tree planting sites
  • Identifying barriers to tree planting for low income communities
  • Providing recommendations on how to best work with communities to plant trees and gain community support for tree planting, with special attention to communities of color and low income communities

Applications are due April 23, 2017

Download the information packet
Download the application

About the Citywide Tree Planting Strategy

Portland State University and Portland Parks & Recreation have partnered to evaluate ways to equitably increase Portland's urban tree canopy.

Portland has a goal of increasing tree canopy and its distribution to improve not only the environment, but also public health and livability. The project seeks to identify the best ways to increase canopy, with a special focus on equity. Currently tree canopy in Portland is below the city’s goal. Additionally, existing canopy is not equitably distributed throughout the city: lower income neighborhoods have significantly lower tree canopy coverage and fewer street trees than other neighborhoods. The reasons behind this inequitable distribution of trees are complex, and influencing factors include property owner income (trees cost money to maintain), past planting practices, quality and availability of planting spaces, pressure from development, and community attitudes towards trees.

Portland Parks & Recreation Urban Forestry (PP&R UF) is committed to improving the equitable distribution of trees in the city. As the responsible bureau for the management and regulation of trees, PP&R UF is mandated to maximize the benefits of the urban forest for all residents (Urban Forest Management Plan 2004). PP&R UF has engaged Portland State University (PSU) to research this important issue and create a Citywide Tree Planting Strategy.

The goals of this project are to:

  • Publish a strategy that includes a city plan analysis, spatial analysis, and recommendations.
  • Ensure historically underserved neighborhoods benefit and are involved in this important work for their communities.
  • Strengthen collaboration around tree canopy goals and planting efforts - internally between Portland city bureaus, as well as externally between the City of Portland and community groups.
  • Create a publicly available, interactive planting map to help identify plantable areas based on city and community priorities.

For more details, contact