The Pink Lady's Slipper (Cypripedium acaule) was adopted as the official state wildflower of New Hampshire in 1991.
Pink Lady's Slippers are also called "moccasin flower", or "Lady's Slipper Orchid". (Shades go from red-ish to light pink)
There's 4 varieties of Lady Slipper. Pink, Yellow, White, & Showy. (Showy variety mostly white with rosy lip, white petals and sepals.)
Some more information on this flower at: http://www.usgennet.org/usa/nh/state/main/lslipper.html
Great shots of the lady slippers. We have this variety growing in the woods behind our home. We live west of Atlanta GA along the GA/AL border. The lady slippers are beautiful in the spring and is always a joy to see them. I just wish that I could take photographs of them as great as you do. Thanks very much for Sharing!