Coefficient of Conservatism:
Coefficient of Wetness:
A single depauperate collection from Michigan has been seen, from forests at Rochester, Oakland Co. (O. A. Farwell 1537 in 1896, BLH).
The spikelets occur at the ends of the long panicle branches in this species, whereas they are crowded on the whole outer half of the branches in P. annua.
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. December 16, 2017. http://www.michiganflora.net/species.aspx?id=2193.