By Jonathan O.C. Kubesch1,2
- Virginia Tech School of Plant and Environmental Sciences, Blacksburg, VA
- Country Home Farms, Pembroke, VA
In the acidic, drier soils of the Bluegrass State and the Upper South, splitbeard bluestem (Andropogon ternarius) graces our landscapes with its elegant presence. This botanical marvel stands at comparable heights to little bluestem (Schizachyrium scoparium), reaching heights of 3 to 6 feet, its feathery seed heads resembling delicate beards that lend an air of elegance to the verdant tapestry of Kentucky’s native flora. This member of the primary bluestem genus is most distinctive at the end of the growing season, generally September to November in Kentucky. Splitbeard bluestem captivates with its slender stems swaying gracefully in the breeze. Its ethereal silvery seed heads add a visual symphony to the landscape, creating a picturesque image in the minds of those who encounter it (Figures 1).
Figure 1. Splitbeard bluestem growing in a working cow-calf grazing system in Carroll County, Virginia. Photo credit: talented, yet unnamed research assistant. September 29, 2023.
Splitbeard and little bluestems can be differentiated from one another quite easily at the end of the season. Little bluestem florets curl up and down the stalk without branching. Splitbeard bluestem seed heads are especially feathery, branching, and generally convey a pinker hue than little bluestem (Figure 2).
Figure 2. Little bluestem (left hand) and splitbeard bluestem (right hand). Both bluestems growing in a working cow-calf grazing system in Carroll County, Virginia. Photo credit: talented, yet unnamed research assistant. September 29, 2023.
Splitbeard bluestem is well documented in the Upper South: particularly in Kentucky and Tennessee. Herbarium specimens catch the species in the Cumberland and Allegheny Plateaus, the Highland Rim, the Ridge and Valley, and the Blue Ridge Mountains. Venturing into Kentucky’s diverse ecosystems, splitbeard bluestem thrives in various habitats, from sunny prairies to open woodlands. Ecotones — transitions between habitats or sun regimess — seem to be a key area to find this native grass (Figure 3). This resilient native weaves its story across acidic, well-drained soils.Splitbeard bluestem consists of a group of native grasses adapted to fire and herbivory in the landscape. Embarking on a journey through ecological history, splitbeard bluestem emerges as stalwart, surviving regular fires, elk (Cervus canadensis), and bison (Bison bison). Codeveloping with the region’s fauna, it has weathered the ages, adapting to the rhythms of fire and contributing to the rich tapestry of native ecosystems.
Figure 3. Splitbeard bluestem growing along an ecotone between open pasture and pine woodland in a working cow-calf grazing system in Carroll County, Virginia. Photo credit: talented, yet unnamed research assistant. September 29, 2023.
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