On July 1, 1805, at Traveller's Rest near present-day Missoula, Montana, Lewis gathered the flowers that would give their name to so many landscape features in western Montana, from the Bitterroot Mountains to the Bitterroot River. Also called the "rockrose" because of its lush pink petals and ability to grow in stoney, seemingly inhospitable spots, the bitterroot was a dietary staple for area tribes who ate the thick taproots. The flowers bloom during the summer, closing at night and unfolding at dawn.

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