Weir White Oaks

Weir White Oaks features an excellent example of an old-growth southern dry-mesic forest dominated by abundant large white oaks with red oak, basswood, sugar maple, and white ash. Also present is butternut (Juglans cinerea) a species of concern in Wisconsin, black walnut, eastern hop-hornbeam, and hackberry. Located on the east side of the Pecatonica River within what was historically a larger prairie matrix, the river protected the grove from the prairie fires that swept across the landscape from west to east. The grove has not been grazed and contains a diverse, well-structured understory dominated by native species. Shrubs include alternate-leaved dogwood, common winterberry, nannyberry, and arrowwood. The extremely rich herbaceous flora includes showy orchis, sweet cicely, blue cohosh, Jacob's-ladder, hairy wood mint, and clustered black snakeroot. Sugar maple reproduction is present in the eastern section of the woods but absent in the west. Wier White Oaks is privately owned and was designated a State Natural Area in 2002.