By Jim Gersbach | Concordia Tree Team
I am often asked by property owners and passersby between Martin Luther King Jr. Boulevard and Fernhill Park when a tree that has died or blown down in a storm will be replaced.
Although a different Portland city bureau actually owns the land in the Ainsworth median, Portland’s Urban Forestry section with the Parks and Recreation Bureau has been kind enough to handle removals and pay for replacement trees.
In the past couple of years, two old Norway maples that were in slow decline finally blew over—one in the middle of the block between Northeast 16th and 17th avenues, and another further east around Northeast 26th. A third tree on the east end of the intersection at Northeast 33rd was struck by a car, revealing serious inner rot. That tree was cut down as a precaution against falling into traffic.
In order to replant, the city must first grind out the stump. With many trees downed in the late April snowstorm of 2022, Portland cleanup crews had their hands full grinding stumps all over town.
At the start of this year, they were finally able to grind the stump between Northeast 16th and 17th. That allowed for the planting of a replacement tree this winter. Urban Forestry plans to stump grind the remaining two downed trees by this end of this year, permitting planting of their replacements in 2024.
Because maples—especially the invasive Norway maple that has dominated the median since the post-World War II years—are seriously overplanted in Portland, Portland Urban Forestry picked a species that was added to the approved street tree list only in the past decade and has not been readily available in a size large enough to plant. That tree is a California interior live oak, Quercus wislizeni. This evergreen oak has small, leathery leaves that are dark green above and toothed somewhat like a holly. New leaves emerge a bronze to reddish color.
Hardy enough to survive a typical Portland winter, California interior live oak grows between the borders of Oregon and Mexico, in both the Coast Range and Sierra Nevada, where it can be found at elevations up to 6,500 feet.
Interior live oak is quite tolerant of drought and heat, as one would expect of a tree from inland California. It should fare well in future extreme hot-weather events. Interior live oak can grow as tall as 60 to 75 feet in good soils with adequate moisture. Its acorns take two years to mature, providing food for squirrels and birds when they do.
The odd-sounding botanical name honors German-born army surgeon, explorer, botanist, and plant collector Frederick Adolf Wislizeni [1810–1889]. Wislizeni opposed monarchical government and eventually had to flee to Switzerland before emigrating in his early 20s in 1834 to the United States. He traveled widely in the American Southwest and Northern Mexico, where he was imprisoned for a time during the Mexican-American War.
Jim Gersbach has been a volunteer tree planter and tree pruner for more than 30 years with Friends of Trees. He has worked for Portland Urban Forestry and as a member of the Concordia Tree Team, has helped inventory the neighborhood’s street trees and advises homeowners on site-appropriate tree options.