Also known in many localities as Cranesbill, this species is a common late spring flower which continues blooming into late August. Found in sagebrush and open woods, the plant grows to a height of one or 2 feet. The rose-purple flowers (1 to 1.5 inches across) are constructed on a plan of five: i.e., all parts are in five or multiples of five. The fruit, which resembles a crane's bill, is unique in its method of seed dispersal; as the capsule ripens, its longitudinal sections split open with such recoiling force that the seeds are catapulted outward from the parent plant for several feet. {Plants of Yellowstone and Grand Teton National Parks by Richard J. Shaw pg 104}
Yellowstone Wildflowers link. This is an Adobe pdf file.
