Places We Protect

Hanging Bog


Hanging Bog in the Lower Cedar Valley in Iowa
Hanging Bog in Lower Cedar Valley in Iowa Hanging Bog in the Lower Cedar Valley in Iowa © Nick Longbucco/The Nature Conservancy

The rare skunk cabbage thrives at this preserve in eastern Iowa.



Hanging Bog is important for the survival of skunk cabbage, a rare plant that thrives here. A cold-water source feeds the site to create the perfect environment for skunk cabbage. Skunk cabbage blooms very early, pushing through the last of the winter snow. This plant, aptly named, has an unpleasant odor and very unusual blooms.

Why You Should Visit

Hanging Bog gets its name from a series of saturated terraces on the lower slopes of the wooded hillsides. These terraces formed from large deposits of porous lime, called "tufa", which were deposited by mineral-rich groundwater that flows across an impermeable layer of buried bedrock and seeps out of the side of the hill. These unique conditions are ideal for the growth of skunk cabbage.


Dominated by porous lime deposits and the notably odorous skunk cabbage. Relatively easy walk, but be considerate as to where walking, some steep ravines. 

Why the Conservancy Selected This Site

Hanging Bog was deeded to the Conservancy by Leslie F. Clarke in 1968. It was dedicated as a biological State Preserve in 1981.

What the Conservancy Has Done/Is Doing

The preserve is an important educational and research resource for local schools, colleges and universities.



Explore our work in this region

What to See: Plants

Skunk cabbage, marsh marigold and jewelweed are the dominant vegetation on the seep. The surrounding forest is dominated by black maple, red oak and basswood, and supports over 170 species of vascular plants, 23 species of bryophytes (mosses and liverworts) and an abundance of ferns.

What to See: Animals

Birds at the preserve include the bobwhite quail, house wren, brown thrasher, wood thrush, American robin, red-winged blackbird and indigo bunting. Mammals here include the short-tailed shrew, white-footed mouse and pocket gopher.

Visitation Guidelines

Please download our preserve visitation guidelines here.