Climate change is affecting North Portland parks

Climate change is endangering shrubs and trees at most major North Portland parks, including Arbor Lodge, Columbia, Kenton, Overlook, Peninsula and Pier parks.

“Many shrubs and trees in our parks aren’t used to three-month summers with excessive heat, without rain, and they’re dying,” said Johnny Fain, who manages several North Portland parks for the Portland Parks & Recreation (PP&R).

On a recent Overlook Park tour, Fain pointed toward an area behind the baseball diamond where a majestic, century-old, 120-foot-high Engelmann spruce that had looked “super healthy” had rapidly declined. Once-thriving native rhododendrons and azaleas nearby have been removed due to heat stress.

Johnny Fain points to native plants at Overlook Park
Johnny Fain points to native plants at Overlook Park

Five miles away in St. Johns, Steve Davis walks a guest past a 300-yard-long corridor of struggling Western red cedars in Pier Park. He noted that when the branches turn brown, the tree is struggling for life. Some of the larger tree branches have become so brittle they’ve snapped, and 40-foot-long branches have twice “taken out the cyclone fence around the swimming pool,” said Davis, who chairs the Friends of Pier Park.

Western red cedars are native to the moist Oregon coastal areas. They have grown well in the drier Willamette Valley for a century, but that is changing. PP&R horticulturists report that Western red cedars in Columbia and Peninsula parks are showing signs of distress. Several Western red cedars died in the far northwest corner of Pier Park, Davis said. Park staff replaced them with a cedar variety native to dryer Texas, but those plantings have failed for unclear reasons.

Steve Davis pointing to cedars with dying branches
Steve Davis pointing to cedars with dying branches

The summer 2020 forest fires helped drive the Portland City Council to create a five-year Climate Emergency Workplan. As the plan’s opening paragraph says, “Nearly every Portlander can tell you where they were in June 2021, when temperatures hit 116 degrees and killed 72 people in Multnomah County.” One of the plan’s central strategies is to sequester more carbon in trees and green spaces, but dying tree cover on park property undercuts that goal.

Low-tech supplemental irrigation can help. “Bump up irrigation, water [shrubs] more by hand, or suffer consequences,” said PP&R Senior Horticulturist Dave Blado, who covers several North Portland parks including Pier and Cathedral. Unfortunately, budgets are often too tight to cover the extra costs of irrigation and labor, which are especially high for mature trees.

The parks bureau has seen some success by planting different species. At Overlook Park, Fain identifies the desiccated skeleton of a Red Plum tree in front of bountiful shrubs and flowers. Unlike the plum, the latter are all native central Oregon varieties, introduced to survive drier Portland summers.

“They virtually never need watering,” Fain explained. While it may seem surreal to see a yucca plant in an urban Portland park, it is beautiful and sustainable. “This could be a model for the entire city,” Fain said.

When native rhododendrons and camellias began dying on the sunbaked west side of Columbia Park in 2021, neighbors helped Fain find a creative solution. The Friends of Columbia Park purchased heat-tolerant manzanitas from southern Oregon that Fain showed how to plant. The trees are now 15 feet tall and require little watering or maintenance. Their vibrant emerald foliage starkly contrasts with the adjoining red cedar’s dead branches.

These successes aside, climate change creates myriad problems for North Portland parks. According to Fain, the problems now include: 

• Shorter and more abrupt seasonal transitions, with severe heat in March and April and severe cold snaps in October
• Drier soils
• Shorter planting windows: “We used to plant from October to March. Now it’s November to January or February, at best,” Fain said.
• More difficulty replanting traditional Willamette Valley varieties: 30-40% of plantings may be lost without frequent watering
• More difficulty restoring damaged or infected plants that are more susceptible to pests and diseases due to climate change

To keep a step ahead, Parks staff are planting more drought-tolerant species such as oaks, madrone and manzanitas. Commissioner Dan Ryan’s recent redirection of $3.6 million in potential PP&B funding to the University Park and Portsmouth neighborhoods could help, Fain said. The money is part of the $108 million budget for the planned Northgate Park Aquatic Center project. Community and neighborhood groups can apply for grants from that fund to help parks adjust to the effects of climate change.

Fain said that PP&R is understaffed and more neighborhood involvement would be immensely helpful. The parks needs more eyes, ears and advocates, he said.