Ghosts of Grasses Past

There’s not much left of the original prairie lands of Texas, but every October phantoms of the “big four” are often seen haunting local parks and roadsides.

Historically many Texas ecosystems were dominated by tall and mid-height grasses. Today there isn’t much left of the original prairie lands. But look around and you might be able to spot some ghosts of what was once one of the most productive ecosystems in North America.

The four most common prairie grasses, often referred to as the “big four,” also happen to be attractive ornamental grasses — and October is one of their most showy months.

Little bluestem (Schizachyrium scoparium) is the first, and in Texas, was probably the most prolific of the big four prairie grasses. Little bluestem grows best in what prairie ecologists term mesic locations, not moist but not as dry as xeric. In spring, little bluestem wakes up in April and creates a tight clump of leaves. As summer wears on, some individuals will take on the namesake blue-green tint, a color known to botanists as “glaucous.” In October, little bluestem blooms and as the seeds mature they give the plant a fluffy halo. When fall gives way to winter, the plants take on a beautiful red color that lasts till the next spring.

Big bluestem (Andropogon gerardii) likes a bit more water than little bluestem but is comparable to other landscape plants. While the life and color cycle are similar to little bluestem, big bluestem grows larger as the name suggests. The inflorescence is different as well, not as fluffy and they often have three branches like the foot of a turkey. The stems of big bluestem are taller, but often don’t remain standing all winter like little bluestem.

Yellow Indiangrass (Sorghastrum nutans) is the showiest of the big four, in my opinion. Like little bluestem, the leaves of yellow Indiangrass tend to be glaucous but wider and the clumps more full. Starting at the end of September, beautiful yellow inflorescences begin to appear, which look quite striking against the blue-green backdrop of the leaves.

Switchgrass (Panicum virgatum) is the most variable in appearance of the four grasses. There are large clump-forming specimens can be used as a filler anywhere a pampas grass would fit. However, there are cultivars that only grow about three feet tall for smaller spaces. Large or small, switchgrass will always produce an open inflorescence know as a panicle.

Picture of Cleveland Powell
Cleveland Powell
Cleveland Powell is a conservation planner for SAWS. He is enthusiastic about grass taxonomy and milkweed propagation. In his free time, Powell enjoys hiking around area parks in search of intriguing bugs, birds and plants.
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