Coefficient of Conservatism:
Coefficient of Wetness:
A. A. Reznicek
Dry forests, apparently very rare or perhaps partly overlooked; presumably not native quite this far east and first collected in Van Buren County in 1906.
This species generally has stouter and longer nodal prickles than the common R. cynosbati, but vigorous sprouts of R. cynosbati can rarely have nodal prickles as large as R. missouriense. A vegetative specimen from Grapevine Point, Douglas Lake (Cheboygan County), that has such stout, long spines has been tentatively named R. missouriense, but is here assumed to be an extreme of R. cynosbati.