August 2018

A restored prairie needs managed

Hanah Hefner, MCCB Naturalist Technician

Grasses sway over your head in the gentle rolling breeze of summer as grasshoppers retreat further from you at every step you take down the path. Butterflies flutter from flower to flower as do bees. A bird swoops in to perch on a thick stem and a rabbit snaps undergrowth as it scurries away. The whole field bustles with life. Everywhere you look is something different.

Long ago, prairies covered Iowa before the rich soil was discovered. After pioneers and homesteaders found the soil to be rich they tilled it up and built Iowa’s economy on farming. With the turning of the prairie, most of this original, diverse ecosystem is gone. Efforts are being made to bring prairie ecosystems back where possible. These new prairie areas must be managed.

Prairie management is important to help the prairie be its most natural state. If the prairie area isn’t managed, trees and invasive species will invade. Managing a prairie can be done the more traditional way of burning or the convenient technique of mowing.

How do burning and mowing help maintain the prairie? Doesn’t burning plants kill them? Unlike trees and the invasive plants brought over from Europe, prairies adapted alongside fire. Before Iowa was settled, periodic natural fire kept the trees from growing to age in succession.

Succession describes the pattern an ecosystem follows as it changes. There are typically five stages of succession from bare ground to forest. Over time, bare ground turns into prairie and then prairie becomes forest unless there is something to reset that progress. Trees take longer to grow then grasses and flowers. Periodic burning of the prairie gets rid of the plants temporarily, fire also stops trees from growing tall enough to change the ecosystem. Burning also gets rid of invasive species that haven’t adapted to fire. By getting rid of these plants, you allow space for more diversity of native species.

Mowing is a newer technique being used to manage prairies. Mowing is more convenient for prairie management because managers don’t need to know wind speed and direction to judge if too dry to burn. Mowing does a great job keeping shrubs and trees out. Despite the positives, mowing the prairie doesn’t get rid of invasive species, so you wouldn’t want to rely only on mowing to manage a prairie.

Another downside to mowing is that it can be too even. Burning leaves patches that are more and less burned. This unevenness allows different plants to thrive in different spots so you don’t end up with a large patch of only one type of flower, but lots of sections of different flowers.

Since fire no longer occurs naturally on the landscape, maintenance is key to prairie management to keep out the invasives and encourage diversity of prairie species. If you’re interested in visiting a prairie, some restoration areas in Marion County, Iowa are Cordova Park, Fifield Recreation Area, Wilcox Public area, and many public areas that surround Lake Red Rock. Jasper County is adjacent to Marion County and holds one of the largest tallgrass prairie ecosystems within Iowa, The Neal Smith National Wildlife Refuge. The refuge is breathtaking and takes you back into history with bison, elk, and the Prairie Learning Center. Taking a short drive to walk through the ancient grasses would be really refreshing.

Learn more here:

Books!

    • Tallgrass Prairie Wildflowers text by Doug Ladd and photos by Frank Oberle (1995)
    • Where the Sky Began: Land of the Tallgrass Prairie by John Madson (1982)

Click on the picture above for a few more photos from the Cordova Prairie.