Solidago rupestris Raf.

Solidago rupestris Raf. View in CoL [ Asteraceae ]

Solidago rupestris is reported as extant in Indiana in Harrison County based on a collection made in 2021 by Scott Namestnik. This specimen represents the first confirmed collection of the species in Indiana in nearly 40 years. The plants were observed growing on a limestone ledge riverscour along the Blue River ( Fig. 25 View FIG ). Less than 30 individuals were noted at this location, which is habitat for at least three other species of Solidago , including one that is federally endangered and globally critically imperiled (G1).

This smooth-stemmed (below the inflorescence), narrow-leaved, small flowerhead subsection Canadensae goldenrod of riverscour habitats has a restricted distribution in the eastern United States, with extant occurrences in Maryland (recently rediscovered after having been considered extirpated for over 100 years), Virginia, West Virginia, Kentucky, Tennessee and now Indiana; it is considered extirpated from Pennsylvania, and the Ohio and Illinois reports in Weakley & Southeastern Flora Team (2022a) seem to be in error ( Kartesz 2015; Weakley & Southeastern Flora Team 2022a). Solidago rupestris is considered globally apparently secure (G4?) and apparently secure in the United States (N4?); it is apparently secure (S4) in Kentucky but is a species of conservation concern and critically imperiled (S1) in every other state in which it is extant ( NatureServe 2023). Given the limited distribution and county distribution in Kentucky (per Kartesz 2015), the national and global conservation ranks may warrant reevaluation. In Indiana, there are historical collections of S. rupestris from Clark and Floyd counties ( Consortium of Midwest Herbaria 2023, Deam 1940). There are collections currently stored as S. rupestris from Lake and Montgomery counties in Indiana ( Consortium of Midwest Herbaria 2023), but these specimen identifications are clearly in error. The species is currently tracked as state extirpated on the list of Endangered, Threatened, and Extirpated Plants of Indiana ( Indiana Department of Natural Resources 2022), but will be moved to state endangered on the next iteration of this list. The occurrence of the species in Harrison County represents the only currently known extant population of S. rupestris in Indiana.

Voucher Specimens: INDIANA.Harrison Co.: Greenbrier Knob Nature Preserve, on limestone ledge along the Blue River,associated species: Allium cernuum , Andropogon gerardii , Baptisia australis , Campsis radicans , Cornus drummondii , Cornus obliqua , Hypericum sphaerocarpum , Lespedeza cuneata , Panicum flexile , Platanus occidentalis , Sorghastrum nutans , Symphoricarpos orbiculatus , Symphyotrichum urophyllum , Toxicodendron radicans , 38.22591, –85.26249, 16 Sep 2021, S.Namestnik 5253 (NCU).