The diversity of forbs in a restored oak savanna is very high, generally higher than in either a prairie or woodland. The reason for this is that the savanna offers both prairie-like and woodland-like areas as well as “true” savanna areas. Thus, in addition to prairie and woodland plants, plants which thrive in intermediate light regimes, savanna specialists, are present. See the work of Stephen Packard.

Savanna Indicator Species

Some of these unique savanna specialists have been called “savanna indicator species.” The list in the table below was developed by a group of experts for the 1995 Midwest Oak Savanna Conference and was collated by Brian Pruka, an ecologist at the University of Wisconsin-Madison.

According to Pruka: “The presence of these light-dependent understory species indicates a recent closure of the canopy. Wooded sites containing sufficient populations of these species, therefore, have the highest potential for recovery if properly managed through the use of prescribed burns, mechanical canopy thinning, and other techniques….[These] are the best indicators of former savannas and open woodlands because they tend to be limited to partial canopy conditions. In more densely-wooded sites, these species are usually in a state of declining vigor due to the ever-increasing canopy closure. They typically persist in densely-wooded sites only near canopy openings such as woodlot edges, roadsides, or brushed utility corridors.”