You should probably find out who owns the property before going dig things up. Maybe contacting the county would help.

I just dug up some Northern Brewer roots. You're certainly welcome to all and any before they get buried in the compost pile.

I contacted the county, city, and visitor's center to no avail.
I understand the local brewery organizes a hops harvest, so I'll try to participate in that and get some more info.

Thank you for the generous offer, gjcore!
I'll see if I can send you a pm.