Lots of tall boneset

Tall boneset, Eupatorium altissimum, is not common in Wisconsin. It is one of the few prairie/savanna species that Cochrane and Iltis give a fidelity number of 1, based on the Curtis data from Vegetation of Wisconsin. "The smaller the number, the rarer the species and the more it is restricted to a particular habitat." (This does not mean that it is endangered or threatened.)

Despite this fidelity number, tall boneset is quite common at Pleasant Valley Conservancy. We have it in prairie remnants, restored savannas, and planted prairies. (All of our plantings of this species came from seeds collected on site.) In Wisconsin its habitat is dry limestone (dolomitic) bluffs, just like Pleasant Valley Conservancy.

All of the white plants in the photo above are E. altissimum.

This species should not be confused with upland boneset (Eupatorium sessilifolium), another savanna species that is even less common. (It is not even included in the Cochrane/Iltis Atlas.) E. altissimum has a Coefficient of Conservatism of 4 and E. sessilifolium has a C value of 9.