1. Leaves all netted-veined, of various shape (basal petioled with broad subcordate blades, upper and midcauline nearly sessile and lobed); bracts more than half as long as the head; petals blue; escapes from cultivation.

E. planum

1. Leaves all parallel-veined, simple and elongate (yucca-like); bracts subtending heads less than half their length; petals white; rare native species.

E. yuccifolium

All species found in Eryngium

Citation:
MICHIGAN FLORA ONLINE. A. A. Reznicek, E. G. Voss, & B. S. Walters. February 2011. University of Michigan. Web. March 19, 2025
https://mifloradev.lsa.umich.edu/flora-demo/#/genus/Eryngium