Sedges Are a Buffet for Bison in the Indiana Dunes
By Alyssa Nyberg
This July we will be busy with harvesting hundreds of pounds of sedge seeds to include in this year’s prairie planting at Kankakee Sands. We will be harvesting twelve different sedges, each one so unique, and really quite lovely, if you just take the time to lean in and look more closely.
When I think about leaning in and taking a closer look, I often reflect on my work with plants and seeds, and how it requires me to put some of those trickier plant species--like sedges--under a microscope to get a much closer look. And when I am looking through the eyepiece of the scope, really seeing the fine details of the seeds or leaves, it gives me a greater understanding and a much deeper appreciation for the plant before me.
So it is with sedges. Not always easy to identify, but very much worth a closer look. One of my favorite sedges is the dark-scaled sedge (Carex buxbaumii). I find the black and green patterning on the seedhead to be a work of art, simply stunning! Though the colors and shapes may vary from species to species, all sedge seedheads are arranged in a similar fashion - a hard seed, enclosed in a papery sack, clustered along a main flowering stalk.
Sedges are in a plant family called Cyperacaea (pronounced SY-per-ay-see-ay), with more than 5,000 species found around the globe. Golden sedge, bottlebrush sedge, porcupine sedge and brown fox sedge are just a few of the 53 native sedge species that would have been here in Northwest Indiana when the area was a vast marshland surrounding the what was once the largest lake in Indiana, Beaver Lake.
How the fish, ducks, herons, sandhill cranes, muskrats, deer and even bison must have feasted on the seeds, leaves, and tubers of all the sedges! Our own Kankakee Sands bison spend much of their grazing time consuming the above ground portion of the sedge plant; allowing a young bison calf born at just 40 pounds to mature to a 1600-pound bull. Sedges stay green, long into the winter, providing nutrition in the harder-to-find-food-months.
Let’s not forget the little grazers that dine on sedges too: aphids, leaf hoppers, leaf beetles, grasshoppers, katydids, moths, and butterflies, such as the endangered Mitchell’s Satyr butterfly whose caterpillars feed exclusively on the common tussock sedge (Carex stricta).
Sedges are related to grasses, but have differences that can be seen by our naked eye and felt by our naked hand, the easiest one being the shape of the stem. Grasses have round stems, and sedges have triangular stems. Sedges have edges! Simply roll the two between your fingers and you’ll find it’s an easy distinction to make.
Native prairie grasses vary in height, from the six-inch tall grass called six weeks fescue, to the more than the eight-foot tall grass named big bluestem. Most sedges on the other hand, typically grow one to two feet in height, and have seed heads that, in true 4th of July fashion, radiate out from the main base in a sort of fireworks display.
Sedges grow in both wet areas and dry areas, depending on the species. To find the dark-scaled sedge, you’ll need to get your feet wet and wander into a wetland. But it will be worth the wade!
In our world today, we are being asked to lean in and take a deeper look at so many things, a worldwide pandemic, racial injustice, food insecurity, a warming climate... It’s a lot to digest. But just as with sedges, closer scrutiny can make a big difference.
Visit Kankakee Sands this summer to stoop, squat, crouch down and lean in to get a better look at the sedges growing in our prairies, to see the beauty of our nature more clearly, and to be inspired with new solutions for a better world.
The Nature Conservancy’s Kankakee Sands is an 8,300-acre prairie and savanna habitat in Northwest Indiana, open every day of the year for public enjoyment. For more information about Kankakee Sands, visit www.nature.org/KankakeeSands or call the office at 219-285-2184.