Roger Batt, with the Idaho Weed Awareness Campaign, describes the history of Rush Skeletonweed in Idaho. It started back in 1961, when it was thought the weed was first brought in from the Spokane, Washington area to Banks, Idaho. At that time there was less than an acre or so in the Banks area, but the State of Idaho decided to expend the weed budget on Canada Thistle instead of treating this Rush Skeletonweed and as a result Rush Skeletonweed has spread throughout a lot of the state. There is about 4 million acres of it estimated in Idaho now. So now what once was a problem that could have been treated is now a huge problem that virtually cannot be controlled.
Note that there are several video "hot spots" available which provide a lot more detailed information.
Panorama and video taken 7/24/06