I first saw these plants along a dirt road in a remote area of Garfield County (below). They were only the remains from the previous year, scattered among the pinyons and junipers, but were very striking in appearance since they stood 8 or 10 feet tall.
I didn't find out the identity of the plant until late summer of the following year, when I went on a field trip to Deer Creek (near Boulder, Utah). This time the plants were growing among scrub oak and were still in bloom, but it was obvious that they were the same thing that I had seen previously. Thanks to Walt Fertig for the identification.