[1] Washington Univ, St Louis, MO 63130 USA
[2] Chicago Bot Garden, Glencoe, IL USA
[3] Martin Luther Univ Halle Wittenberg, Inst Biol, Geobot & Bot Garden, Halle, Germany
[4] Helmholtz Ctr Environm Res, UFZ, Dept Community Ecol, Halle, Germany
[5] German Ctr Integrat Biodivers Res iDiv, Leipzig, Germany