Please try our next iteration of the Michigan Flora Online here. Beginning on February 1, 2023, will point to this new site.

The new site offers several benefits over the existing website, including real coordinate mapping, giving a clearer view of the density of documentation as well as more precision about plant distributions and their link to landforms. We will also have the ability to update species pages more regularly, both in terms of new collections and as more existing Michigan specimens are georeferenced. In addition, we have a better photo display, and offer indented keys.


Our two species are both annuals, of weedy habit. Clinopodium acinos and C. vulgare resemble Hedeoma, but these (even if corollas and stamen number are not obvious) can be easily distinguished by the nature of the pubescence on the calyx lobes.

1. Leaf blades linear, sessile, entire; cilia present on all calyx lobes.

H. hispida

1. Leaf blades ± elliptic, short-petioled, often weakly and irregularly toothed; cilia present on only the lower 2 calyx lobes.

H. pulegioides

All species found in Hedeoma

Hedeoma hispidaROUGH PENNYROYAL 
Hedeoma pulegioidesAMERICAN PENNYROYAL 


MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. January 29, 2023.