Around here, I bet they're Cascade hops since they're one of the most popular. "Northwest" hops are generally any that start with C, like Columbus, Cascade, Chinook, Centennial, etc. If you leave the root ball as it is, you'll get a lot of cones this year. If you cut it up it will be just like planting a bunch of first year rhizomes, which can take up to three seasons before they produce with any quantity.
That giant root ball is ruined, give me your address and I'll come remove it under the cover of darkness.