The Labrador tea population in the Cedarburg Bog is a southern outlyer from its more northerly range and is disjunct by at least 40 miles from the nearest population. The discovery of Labrador tea in the Bog raises to 11 the number of vascular plants that reach their absolute southernmost Wisconsin boundaries in the Cedarburg Bog (5 dicots, 5 monocots, 1 gymnosperm). It raises the number of vascular plants at, or near, the southern edge of their range in the Cedarburg Bog to at least 35.
Reinartz, J.A. 1985. Labrador tea (Ledum groelandicum) in the Cedarburg Bog. Field Station Bulletin 18(1): 22-23.