Loess Hills

"This is something worthy—it screams for protection."

                 —  Bill Leonard, The Des Moines Register editorial board member, retired.

Two hundred years ago when Lewis & Clark first stood on the Loess Hills and viewed the Missouri Valley, Iowa was three-quarters prairie. Now, only 0.1 percent remains and 50 percent of that is in the Loess Hills.  Sergeant Floyd, the only person to die from the Lewis & Clark expedition, is buried on one of the Loess bluffs overlooking the Missouri River.  The river bearing his name enters into the Missouri nearby.

What’s at Stake

The Loess Hills are a unique landform of wind-blown silt (loess) up to 200 feet high.  The only places in the world loess accumulates to such heights are in Western Iowa, Northwestern Missouri and along the Yellow River in China.  The Loess Hills are a biological crossroads between the Eastern deciduous forest and the Western mixed-grass prairie.  The Eastern slopes are woodland with Dutchmen’s Breeches and Scarlet Tanagers while the Western slopes are prairies with species normally found hundreds of miles west such as Yucca, Cowboy’s Delight and Prairie Rattlesnakes.  It is the home of the diminutive endangered Loess Hills Fern.  Most of the Loess Hills is in private ownership with small tracts owned by the State of Iowa and the Nature Conservancy.


The Threats

Much of the Prairie on the Western slopes is rapidly being overgrown by brush and cedar trees since fire was suppressed in the last century.  Large areas of loess are carted away for fill in metropolitan areas such as Omaha.

catsteps in the Loess Hills


The Solutions

The National Park service has recommended National Reserve Status for the Loess Hills in Iowa.  After evaluating the challenges and opportunities for management of the Loess Hills, the NPS:

  • Recognizes the national significance of the Loess Hills landform region.
  • Encourages and enables local units of government to develop measures to protect the resources of the Loess Hills.
  • Provides for Federal participation in protection of the Loess Hills at a level of involvement supported by local units of government and citizens of the region.
  • Provides for recognition and technical assistance beyond what is currently available through existing National Park Service programs.
Sylvan Runkel State Preserve

Reference material

Read article about the Loess Hills by Sam Hooper Samuels, "Prairie Islands", from March/April, 2005,  Sierra

Article in America's Wild Legacy

Article in America's Great Outdoors

Loess Hills Alliance, The Loess Hills of Western Iowa, "Common Vision and Comprehensive Plan 2011"