The grasses are dormant, their brown leaves poking the sky as they float in one of the now-frigid lily ponds in Lincoln, Nebraska's Sunken Gardens — the 1.5-acre public garden at 27th Street and Capital Parkway. During the summer season, the garden contains 30,000 living plants, bright bursts of color layered on the pocket of land where koi fish swim merrily in their ponds.
It is here Alexa Davis, graduate student with the University of Nebraska-Lincoln's School of Natural Resources, first anchored her living, floating treatment wetland — a collection of 12 Nebraska native wetland sedges and milkweed planted in holes in
