These Northern mule's ears were very common along the south and east facing slopes along Blacktail Creek.
They are easily confused with Arrowleaf balsamroot, and I may be wrong on this identification.
Here is a good link with a picture of the two species next to each other.
Check out the bottom of the leaves here to see why I would rule out Arrowleaf.
Here are some Arrowleaf balsamroot from 50 miles or so to the south.
June 2008.