Hey Weylin,
I'm kind of in the same boat. I live in SW Washington and attend college in eastern Washington. So, it almost feels like Yew is at my fingertips yet still unattainable. I have been reading the forest service policies lately for the Wenatchee and Gifford Pinchot Nat'l Forest to get an idea of what the rules are for harvesting. It maybe different in Oregon but here to harvest what would be a bow stave, the forest service calls it a "post or pole" and describes it as any material 8 feet long and up to 5 in in diameter. The permit is $20 and each piece is $0.25
Maybe that will help you. I just waiting for a free weekend to head to the forest station to ask some questions and hopefully harvest some yew and vine maple.