The following is an article written for the Decorah Newspapers, published in the 21 May 2002 Decorah Public Opinion by Anna Carlson and Marissa Knehans, students in the spring 2002 Environmental Studies Senior Seminar course taught by Associate Professor of Biology Kirk Larsen at Luther College.

Tallgrass Prairie: An Essential Part of Iowa's Natural Heritage

Before the late nineteenth century, almost one-fifth of North America was covered by prairie. Prairie dominated much of the landscape between the Rocky Mountains and the Mississippi River. This ecosystem was home to a wide variety of plants and animals, including more than 500 species of plants, 34 species of amphibians, 90 species of reptiles, and countless species of birds, insects, and mammals.

Pictured at right is Anderson Prairie on the Luther College campus during July 2001, 3 years after planting.

Tallgrass prairie comprises the eastern third of the prairie region and once covered over 148 million acres of the Midwest. Over 80% of what is now Iowa was tallgrass prairie. This region is referred to as "tallgrass" because it receives more precipitation than prairie regions further west. As a result, grasses and other plants that grow here are significantly taller than their mixed grass and shortgrass prairie counterparts.

Conversion to Row Crop Agriculture

During the late 1800's, rapid settlement of the Midwest began. The primary attraction to the area were the fertile, black soils that prairie had created over thousands of years. Plows were brought in to cultivate this optimal agricultural land, and in less than a generation, most of the tallgrass prairie in Iowa was plowed under. Row crops like corn, soybeans, and wheat replaced native plants, and the animals of the unlimited prairie were forced to live in small remnants of their former habitats. Many of them, like bison and prairie dogs, were extirpated due to a loss of habitat.
Today, less than 0.1% percent of the 30 million acres of original Iowa prairie remains. Along with the rich biodiversity of the prairie, many of the environmental services provided by this unique ecosystem have been lost. These services include the creation of new topsoil, preventing soil erosion, improved water quality, recycling of important nutrients, and storage of atmospheric carbon. Modern agricultural practices are unable to provide these important ecological benefits with economic consequences.

Prairie Preservation and Creation

In recent years, concern for the loss of prairie from Iowa's native heritage has increased. Efforts to preserve native prairie remnants and to construct new prairie sites have sprouted all over the state, including here in Decorah. One of these constructions is at Luther College, where 24.7 acres of land has been transformed into prairie.

Anderson Prairie, on the Luther College campus across College Drive from the city pool, was created in several phases. In May 1988, the hillside that had been planted with corn was planted with five species of native grasses and ten species of forbs (wildflowers) to help curb erosion. Erosion control by native prairie plants is attributed to the vast root system that prairie plants develop to anchor themselves in place that allow them to survive the harsh continental climate of the Midwest. Many prairie plants have extensive root systems that extend 25 feet deep into the ground. In comparison, most of the crops in our fields and grasses in our yards are introduced species such as corn and bluegrass that rarely reach more than one foot deep into the soil.

In November 1998, the lower area of Anderson Prairie near College Drive, which had been planted to oats for many years, was planted with five species of native grasses and 71 species of native forbs. This was in return for the construction of Baker Village by Luther College, which was built on a small area of the older prairie that had not grown well and consisted mostly of weeds.

To manage Anderson Prairie, the prairie is divided into 18 plots, each separated by mown walking paths. The plots are burned on various rotations to mimic the natural process of prairie fire that is crucial to maintain the prairie ecosystem. Fires keep out woody species that would take over the prairie, and also accelerates nutrient cycling by burning dead organic lying on the soil surface. Removal of this layer of plant litter allows the sun to warm the soil, stimulating prairie plant growth.

Pictured at left is a prescribed fire in early April on Anderson Prairie at Luther College. Fire is an important part of the ecology of prairie, and is used to remove leaf litter, allowing the sun to warm the soil and stimulate growth of native grasses and wildflowers, while preventing the growth of invasive woody trees and shrubs.

The walking paths through Anderson Prairie are an excellent resource for Luther College and the Decorah community. Students venture into the prairie to observe and study the unique plants, animals, and insects, and it serves as a valuable teaching and research tool for the college. Members of the Decorah community take afternoon jogs or walk their dogs through the relaxing atmosphere. Even the occasional deer or wild turkey meanders through the grass in search of a snack.

New City Prairie Project

Another exciting prairie project beginning this spring and summer is the construction of the new city prairie park along the Upper Iowa River. This prairie will cover 23-acres between the dike and the Upper Iowa River south of the Aase Haugen Home. Like the area that is now Anderson prairie, this land was once used as a cornfield. However, as flood plain, this area is subject to frequent flooding and severe soil erosion. By converting the land to tallgrass prairie, the land will be able to hold soil and capture sediment during flooding, slow runoff, reducing flooding downstream.

It will be exciting to watch this new city prairie grow and develop. Planted prairie may take three to four years to begin to establish itself. The first few years, grasses will devote most of their energy to root growth and development below ground, and may appear small above ground. Native prairie wildflowers, for this same reason, take several years to display their full beauty. A small portion of this new prairie construction will be reserved for a butterfly garden sponsored by the Fullerton family and will display a large number of the prairie wildflowers and grasses throughout the summer.

Anderson Prairie and this new city prairie stand as a reminder of Iowa's natural heritage. Feel free to take a stroll amongst the tall grasses and forbs and let your mind wander back to the days when bison and elk roamed the land. Take time to look within the grasses for a bird or rabbit that may be hiding there. Especially, glance around and appreciate the richness of life that the original prairie gave us while preparing the rich soils we use today for agriculture. These prairies are for the enjoyment of all those who wish to wander freely in open spaces that are filled with a wide diversity of life.

Revised August 2007