Sporobolus compositus (Poir.) Merr.
Common Name: ROUGH DROPSEED
Synonym: Sporobolus asper
Coefficient of Conservatism: *
Coefficient of Wetness: 5
Wetness Index: UPL
Physiognomy: Ad P-Grass

Sporobolus compositus A. A. Reznicek

S. asper of Michigan Flora.

Dry to moist fields, dry road and rail verges. Native east and south of Michigan, but probably adventive here despite some collections from dry prairies. The earliest collections were not until 1931, in Berrien and Wayne Cos.; the Wayne Co. collections from along a railway. Now becoming abundant in the medians and along the shoulders especially of major highways.

Even more than the common S. cryptandrus, the mature inflorescences usually remain within the sheaths, except for the very tip, but the enveloping sheaths do not bend into a sickle-like form. Also the long filiform-involute leaves are very different from the flat, short blades of S. cryptandrus, and give a distinctive reddish-bronze fall coloration to highway sides where abundant.

Locations

Berrien County
Branch County
Clare County
Genesee County
Gladwin County
Ingham County
Jackson County
Kalamazoo County
Lenawee County
Menominee County
Monroe County
Montmorency County
Washtenaw County
Wayne County

Citation:

MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. November 18, 2019. https://michiganflora.net/species.aspx?id=2232.