Prairie dropseed is a native perennial bunch grass that forms dense clumps of fine, light green, arching leaves. The leaf blades are about 16 inches long and only about ⅛ inch wide; they commonly have the margins rolled inward but may also be flat or folded. The leaves often arch gracefully outward from the clump. The seed heads are airy, open, branching clusters bearing small, ovate spikelets (which each contain only a single floret), each on their own individual branchlets. Each spikelet is about ⅛–¼ inch long. Flower heads develop August–October.
Similar species: Ten species in genus Sporobolus have been recorded for Missouri. This is the only common species that has open seed heads.
Height: flowering stems 12–40 inches.
Scattered nearly statewide, but apparently absent from the Bootheel lowlands. Its broad North American distribution extends from Canada, Minnesota, and South Dakota south to Texas and Colorado and as far east as Connecticut and North Carolina.
Habitat and Conservation
Occurs in upland prairies, dry upland forests, savannas, glades, and ledges and tops of bluffs, usually on dolomite or chert substrates, and rarely fens. It also grows occasionally along railroads and in open, disturbed areas. This attractive native grass is also planted as a drought-resistant ornamental in gardens.
Status
Native perennial warm-season bunch grass.
Human Connections
Prairie dropseed grows slowly and takes a while to get established, but as a garden ornamental ground cover or accent plant, it is worth the effort. It forms tufts or clumps that are a little more than 1 foot high and about 2 feet wide of arching, thin, pale-green leaves. The clouds of well-separated, tiny rounded flowers float well above the leaves (up to about a yard high) and smell something like coriander. It is excellent for hot, dry areas. It is drought tolerant and survives deer, a wide range of soil types, and being near black walnut trees. It is easy to grow and prefers dry, rocky, well-drained soil and full sun.
Ecosystem Connections
A variety of sparrows and other seed-eating birds eat the small seeds of this native grass. Grasshoppers, deer, and other herbivores eat the leaves. Two species of leafhoppers apparently are limited to feeding on prairie dropseed; like other leafhoppers, they suck the juices from the plant.
Prairie dropseed’s tufts of arching leaves create perfect hiding places for rodents and other animals that need to avoid predators from above, such as hawks. For snakes and lizards, the arching foliage makes shady little cabanas that can help them regulate their body temperature on hot sunny days.
