Grass family (Poaceae)
Description: This native perennial grass is 2-3' tall and tufted at the base. The culms are tan or reddish brown, hairless, and terete; the base of each culm is erect, rather than decumbent across the ground. Alternate leaves are produced primarily along the lower half of each culm. The leaf blades are up to 10" long and ¼" across, light green or light blue, hairless or slightly pubescent, and curling outward. The leaf sheaths are light green or light blue, hairless or slightly pubescent, and finely ribbed. Each culm terminates in several ascending racemes of spikelets. Each raceme is about 1½3" long and it has a peduncle (or flowering stalk) of variable length underneath. Several pairs of spikelets occur on opposite sides of the raceme's rachis (central stem); this rachis is covered with long white hairs and it tends to zigzag between the spikelets as they become mature. For each pair, there is a fertile spikelet that is sessile and a sterile spikelet on a slender pedicel. The fertile spikelet is about ¼" (6 mm.) in length (excluding any awns); it consists of a pair of outer glumes and a pair of inner lemmas. The narrow glumes are light green to tan and hairless or slightly hairy. The fertile lemma is tan to reddish brown and it has a slender white awn about 1/3" (10 mm.) at its apex; this awn can be straight to strongly curved. The sterile spikelet is about one-half the length of the fertile spikelet and it also has a slender white awn. The florets have anthers that are brown or reddish brown and plumose stigmas that are pale purple. The blooming period occurs from late summer into the fall. Each fertile spikelet produces a single elongated grain. The root system is fibrous and rhizomatous. Tight bunches of culms and leaves are produced from the short rhizomes. The culms and leaves become various shades of tan, brown, or wine-red during the fall and winter.
Cultivation: The preference is full sun and mesic to dry conditions. Different kinds of soil are tolerated, including those that contain clay-loam, gravel, or sand. Less fertile soil is preferred because of the reduced competition from taller vegetation. Because of its C4 metabolism, Little Bluestem develops primarily during the warm weather of summer and early fall, and it has excellent drought resistance.
Range & Habitat: Little Bluestem is occasional to locally common in most areas of Illinois, although voucher specimens haven't been collected in some counties (see Distribution Map). Habitats include hill prairies, gravel prairies, sand prairies, black soil prairies, clay prairies, scrubby barrens, rocky slopes of thinly wooded bluffs, sandy savannas, hilltop glades (limestone, sandstone, or shale), sand dunes, gravelly areas along railroads, and abandoned fields. Little Bluestem is often used in prairie restorations and it is occasionally found in gardens as an ornamental grass. In Illinois, this is one of the dominant grasses of hill prairies.
Faunal Associations: The caterpillars of several skippers feed on the leaves, including Atrytonopsis hianna (Dusted Skipper), Hesperia leonardus (Leonard's Skipper), Hesperia metea (Cobweb Skipper), Hesperia ottoe (Ottoe Skipper), Hesperia sassacus (Indian Skipper), Nastra lherminier (Swarthy Skipper), and Polites origenes (Crossline Skipper). A skipper looks like a cross between a small moth and a small butterfly. This insect is common in prairies where Little Bluestem and other grasses occur. Many grasshoppers feed on the foliage (see Grasshopper Table); they are common in prairies and an important food source for many birds. Other insects that feed on Little Bluestem and closely related Andropogon spp. (Beard Grasses) include several oligolectic spittlebugs, leafhoppers, thrips, and beetles, including Prosapia ignipectus (Black Spittlebug), Flexamia delongi (Leafhopper sp.), Laevicephalus unicoloratus (Leafhopper sp.), Illinothrips rossi (Thrips sp.), and Aniostena nigrita (Leaf-Miner Beetle sp.). The Field Sparrow, Tree Sparrow, Slate-Colored Junco, and other small songbirds eat the seeds, particularly during the winter. The foliage of Little Bluestem is quite palatable to bison, cattle, and other hoofed mammalian herbivores.
Photographic Location: The wildflower garden of the webmaster in Urbana, Illinois.
Comments: Little Bluestem is an attractive prairie grass, particularly during the fall. While the stems of other grasses become matted during the winter, the stems of Little Bluestem remain conspicuously upright. This species is somewhat variable in the appearance of its foliage and the hairiness of its floral racemes. Glaucous forms with blue summer foliage can be found in dry gravelly areas along railroads, while forms with reddish fall foliage are often cultivated. An older scientific name for this species is Andropogon scoparius. However, the floral racemes of Little Bluestem occur individually on slender stalks, while the floral racemes of Andropogon spp. (Beard Grasses) occur in groups (often in finger-like clusters from the same stalk). This is the only Schizachyrium sp. in Illinois, although other species in this genus can be found in southeastern or southwestern areas of the United States. They differ from Little Bluestem in having racemes with longer hairs (at least ½" in length) and culms that are partially decumbent on the ground.