Plant ID

I am trying to ID this plant. It has feathery type leaves and delicate white flowers. It’s root is distinctive as well. It smells like licorice and looks like a peeled white potato. I thought it might be a hemlock but it’s not purplish at the base and the root was described as dark in color.
Other than those two things it really looks like hemlock. I ruled out yarrow because leaves are more delicate than the yarrow. It could be Ligusticum porteri or chevril. It’s growing all over a shady back yard. The rest of the yard is planted in nw natives but hasn’t been tended in a while.

Posted by Susan36 on April 23, 2020