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.


This is strictly an Old World family. All of our species are European natives, escaped from cultivation or otherwise naturalized. The flowers are in a dense involucrate head, but can be distinguished readily from those of the Asteraceae by the 4 corolla lobes and 4 conspicuous, separate stamens. The achenes in our species are hairy (glabrate in Succisella inflexa).

1. Involucral bracts with a prolonged spine at the tip, more than 4 times as long as wide; stem with broad-based prickles; flowers uniform; receptacle with a spine-tipped bract subtending and exceeding each flower.


1. Involucral bracts without spine at the tip, the outer ones less than 3 times as long as wide (excluding marginal bristles); stem glabrous or hairy but not prickly; flowers various; receptacle merely hairy or with short spineless bracts.

2. Leaves (at least middle ones) pinnately lobed; stems pubescent; flowers toward outside of head distinctly larger (and showier) than central flowers; calyx bearing 8 (or more) prominent but deciduous awns; receptacle hairy but without bracts; achenes hairy, obscurely 4-ribbed.


2. Leaves unlobed (± lanceolate and nearly or quite entire); stems (not peduncles) glabrous (or finely pubescent at the nodes); flowers nearly uniform in head; calyx very short, awnless; receptacle with bracts shorter than achenes; achenes glabrate, strongly 8-ribbed.



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