Snow on the Mountain is a native weedy plant found around in pastures in the area. Belonging to the family of Euphorbias, which are a family of succulents. This means they are drought tolerant and need full sun. Like its relative the poinsettia, the plant has colorful bracts (mostly white) with tiny yellow-green flowers. Like all Euphorbias, the juice in the stems is a bitter, milky-white sap. This makes them resistant to deer, rabbits, grasshoppers, and other pests.
The new cultivars are more colorful (white bracts) and come in height up to 4 feet. This makes them useful for a focal point, borders, or as a cut flower (being careful of the sap which causes some people skin irritation). This was one of the plants that Lewis and Clark found interesting and took back with them.
The photo of this plant, stands 4 foot tall and 3 foot wide.