When do the first birds return to Wisconsin? What are the first wildflowers to bloom! When do the lakes ice up? Aldo Leopold author of A Sand County Almanac, studied phenology, recording the spring arrival of birds and the blossoming of plants at his famous "shack" in southern Wisconsin from 1936 to 1947. His daughter Nina Leopold Bradley follow in his footsteps. Listen to our podcast and see what they’ve learned about the arrival dates of birds and the bloom dates of plants and how it has changed over the years.