Flora Fact: A Patch of Blue
Big bluestem provides small animal homes, prevents erosion.
By Sheryl Smith-Rodgers
Come fall, the dense stands of big bluestem that blanket much of Penn Prairie at Cedar Hill State Park fade into reddish browns and beiges, turning the 13 acres into a seemingly dull, lifeless place. But take a closer look at the leggy bunchgrasses, and you’ll find that’s not the case at all.
“Even as big bluestem nears the end of its life cycle, the grass provides shelter and nesting material for birds, small animals and insects,” says Michelle Varnell, park interpreter.
In a habitat, big bluestem grows from 3 to 10 feet high and turns blue-green during the summer. Purplish, three-branched seedheads resemble a “turkeyfoot,” another common name for the grass. Root systems can burrow as deep as 10 to 12 feet, allowing the perennial to survive drought and fire. Its strong rhizomes and fibrous roots help anchor soils and prevent erosion.
Historically, Andropogon gerardii once heavily vegetated the vast tallgrass prairies that stretched across the Midwest. In fact, big bluestem tops the “big four” native species (along with little bluestem, Indiangrass and switchgrass) that typified a tallgrass prairie. Gradually, though, those enormous grasslands that once nourished bison in the 1800s gave way to crops and farms. Today, only small remnants, such as Penn Prairie, remain.