An invasive, tree-killing pest has made its way to Portland, spelling trouble for the many ash trees that cool residential neighborhoods on hot summer days. On Wednesday, Oregon forestry officials announced the discovery of an emerald ash borer infestation in the Hazelwood neighborhood in Northeast Portland. The affected trees will need to be removed. The emerald ash borer made its way to the US from Asia in 2002, first decimating ash trees across the Midwest. Many tree experts say it’s not a matter of if, but when Oregon’s ash trees endure a similar fate. Forestry officials say Oregon will lose 99% of its ash trees to this pest in time. …Oregon has its own native ash tree, the Oregon ash, which is prevalent around low-lying lakes, streams and rivers. Biologists worry that losing Oregon ash trees will make waterways more vulnerable in the face of climate change.