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The 2014 Loess Hills Prairie Seminar
May 30 (evening) to June 1 (noon)
These Special Loess Hills

The Loess Hills Prairie Seminar is sponsored annually by Northwest Area Education Agency for educators, students, park and conservation persons, community leaders, and citizens. It is held at the Loess Hills Wildlife Management Area northeast of Onawa, Iowa and in Onawa at the West Monona High School. See  maps and more information.

The Loess Hills Prairie Seminar is in its 38th year. It brings together dozens of facilitators and hundreds of participants of all ages, with diverse interests that relate to natural and cultural history, the Loess Hills, and prairie. Many field sessions teach about plants, insects, and birds, some explore nature writing or photography, several offer information about using native plants in the landscape, others feature Native American stories and rituals, and there are many more topics explored.

The public is invited to attend any session or program of interest. There is no registration fee and pre-registration is necessary only for those ordering meals or registering for one of three special offerings this year: the Missouri River Boat Tour, the Introduction to BugGuide, or if you want to make the PVC herbicide applicator at the end of the session on Invasives. That make-and-take workshop is the only one with a small fee. See the registration document to register for any of these. There is limited space on the boat tours.


Hyperion Threatens Loess Hills

If the Hyperion Energy Center, a 400,000 barrel-per-day oil refinery and a 200 MW integrated gasification combined cycle power plant at the southeastern tip of South Dakota, is built as proposed, the industrial air pollution would set back more than 25 years of prairie preservation in the northern Loess Hills. The proposed refinery would jeopardize The Nature Conservancy’s Broken Kettle Grassland and its bison herd, Iowa’s premier native prairie. Situated within 10 miles of the refinery perimeter, the bison and the grassland would be subject to “short-term significant impact” acknowledged by Hyperion. Joy Hollow Girl Scout Camp and Five Ridge Prairie would also see effects. Soil and vegetation studies of these biologically diverse prairies have not been completed.

The prevailing winds move from the northwest to the southeast, thus directing the emissions toward Sioux City and the northern Loess Hills.   The refinery will be emitting a number of hazardous air pollutants -- toxic chemicals that are known or suspected to cause cancer, to cause birth defects, to cause serious health effects, or to cause adverse environmental effects.  Examples of hazardous air pollutants (HAPs) that are emitted by an oil refinery include benzene, hydrogen sulfide, toluene, xylene, napthalene.  In fact the refinery will be processing heavy, sour crude.  Sour crude has a high sulfur content.  Currently the federal Environmental Protection Agency has identified 187 hazardous air pollutants.  See a complete list.

There are several HAP monitors in Iowa that test for the presence of hazardous air pollutants in the air where they are installed.  Yet there are no HAP monitors in the Sioux City area, near where the refinery is proposed to be built.

Sierra Club Iowa Chapter staff and volunteers offered information about the refinery at the 2011 Loess Hills Prairie Seminar.  The Sierra Club crew also collected postcards asking the Department of Natural Resources to install a HAP monitor in or near Sioux City.  

Materials related to the proposed refinery can be found here. 




Picture Gallery of  the Loess Hills during the 2011 Loess Hills Prairie Seminar

Volunteers Ginger Soelberg (left), Jim Redmond and Chapter Director Neila Seaman provided information to participants at the seminar, enjoyed the prairie flora, hiked the Sylvan Runkel State Preserve and found workers performing a prescribed burn.



































Photo by Holly Johnson



"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.


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.




Frequently Asked Questions


Loess Hills Featured in Sierra Magazine

If you haven't seen it, check out the Sierra Magazine's March/April 2005 issue and read about the Loess Hills, their unique geology found only in Iowa and in China and much more.  Click here for the article...









You can make a tax deductible donation to the Iowa Chapter.