Freda Haffner Kettlehole State Preserve

About the Freda Haffner Kettlehole Preserve

The Freda Haffner Kettlehole is the largest glacial kettle in Iowa, of which 12.4 acres were acquired by The Nature Conservancy in 1972. In 1976, a total of 110-acres, including the kettlehole and surrounding prairie, was dedicated as an Iowa State Preserve, which is open to the public.

The knob and kettle landscape of this area formed 12,000 to 13,000 YBP as ice from the Wisconsin Glacier melted and deposited sand and gravel stored in a network of stream channels flowing within and on top of the glacial ice. These sand and gravel deposits form steep hills and ridges of varying solar aspect on today’s landscape. In areas with slow to melt chunks of ice, low areas formed between the sand and gravel hills, forming kettles where wetlands and small lakes can form. As such, knob and kettle landscapes provide an assorted array of environmental conditions, promoting biological diversity through diverse habitat assemblages ranging from very dry to very wet conditions in a relatively small expanse.

Pollen recovered from soil cores of the preserve indicate that coniferous forests occurred on this site shortly after the Wisconsin Glacier receded. As time progressed, the coniferous forest gave way to deciduous forest and then to prairie due to a warming climate.

Despite past grazing of this site, the preserve houses over 250 species of native prairie plants, including a Federally Threatened plant species.

Amenities

There are no maintained trails restroom facilities at this site. Off-road parking is available.

How to Get There:

Nearby Sites of Interest:

Interesting literature

• Click here to view a Google Scholar search for additional literature using the pre-filled search terms of "Freda Haffner Kettlehole Iowa"

• Freese, Edwin L., and William J. Platt. "Vascular Flora of Arend's Kettle, Freda Haffner Kettlehole State Preserve, Dickinson County, Iowa." Journal of the Iowa Academy of Science: JIAS 98.2 (1991): 102-107.

• Herzberg, Ruth and John Pearson. 2001. The Guide to Iowa’s State Preserves. Bur Oak Guides Iowa City, Iowa.214 pp. This guide provides information and maps for State Preserves throughout the state of Iowa.

• Thompson, C., Prior, J., Quade, D. 1991. Quaternary Landforms and Hydrogeology of Fens in Clay and Dickinson Counties or Mucing about in Northwest Iowa. Geological Society of Iowa Guidebook 54. 35 pp.