There currently are no publicly-advertised mailman mailing lists on lists.extension.umn.edu. To visit the info page for an unadvertised list, open a URL similar to this one, but with a '/' and the right list name appended.

List administrators, you can visit the list admin overview page to find the management interface for your list.

(Send questions or comments to mailman-owner@lists.gis.umn.edu.)