It is a nice shrub though. Definitely informal, there is a place for it in woodland clearings. And I forgot to mention that it's thornless. There is no scale in the picture,but the flowers are large, 2" or so across. And disease free.
This plant is in Fern Valley; many of its siblings were sacrificed to the trail renovation project. The greater part of the colony was repeatedly, several hundred times?, driven over by a Bobcat moving soil, gravel, or whatnot. We put down a thick layer of wood chips and particle-board, but only a couple plants in the area that was the temporary roadway survived. I'm not worried. Adjacent plants are already moving into the devastated area. I expect that by the end of next summer we ought to have the planting back in its entirety.