Pink Lady’s Slippers (Cypripedium acaule), also known as Moccasin Flowers, differ from Yellow and Showy Lady’s Slippers in two fairly obvious ways. One is that the stalk the single flower is borne on bears no leaves. In addition, the pouch, or labellum, has a vertical slit running the length of it, rather than an oval opening on the top. Bumblebees are the only insect strong enough to push their way through this slit and are their main pollinators. In New England, almost 25% of the Pink Lady’s Slipper population have white flowers (see insert).