Abstract Detail

Floristics & Taxonomy

Groffman, Dominique [1], Block, Timothy [1], Skema, Cynthia [1].

A niche analysis of Ripariosida hermaphrodita (Malvaceae), Virginia mallow.

Ripariosida hermaphrodita is a rhizomatous perennial native to the eastern half of North America, with a range from Tennessee north to Ontario and from Indiana east to Pennsylvania. The species is globally vulnerable and is considered extirpated or imperiled in most of its range. With growth up to 4 meters in one season, this substantial plant is a biofuel crop in Europe. Of further interest, its closest relatives are strictly Australasian, members of the Plagianthus alliance (tribe Malveae), as shown by phylogenetic evidence that prompted its recent move from the genus Sida into the newly named Ripariosida. A phylogenetic and developmental interest motivates our research into Virginia mallow, and we began our studies with a niche analysis to better understand the species and its distribution. Herbarium specimens of R. hermaphrodita, representing 248 unique collections of wild material, were categorized into levels of geographic certainty (from none to most): 51 specimens could not be georeferenced (Level 0), 83 were georeferenced from general locality statements (Level 1), 106 were georeferenced from precise locality statements (Level 2), and 7 specimens had GPS coordinates taken at the time of collection (Level 3). Analyses were completed on subsets of specimens defined by these levels to understand the effects of georeferencing uncertainty on results. Using specimen coordinates, we extracted climatic, soil, topographic, land use, and proximity to nearest water/transportation data in ArcGIS to examine the niche of R. hermaphrodita. Occurring most frequently in flood plains, stream terraces, slopes, till plains, (rail)road cuts and urban land, Virginia mallow favors disturbance, both natural and mechanical, and is tolerant of both drought and periodic inundation. The most common soil type found for Virginia mallow was loam, of various kinds, followed by ‘urban land.’ Ripariosida hermaphrodita also clearly prefers high sun exposure, with south/southeastern exposures most common and no recorded northern exposures. Its tendency to occupy disturbed and at least intermittently wet areas was underscored by a mean distance to nearest road/railroad of 83 m and to nearest water of 165 m for Level 1-3 specimens. Future field work will focus on the recording of precise geographic coordinates for populations (known and new) and tissue collection for molecular work. Population genetic studies may help differentiate garden escapees from natural populations and may illuminate past demographic changes and ancestral regions.

1 - Morris Arboretum of the University of Pennsylvania, 100 E. Northwestern Avenue, Philadelphia, PA, 19118, USA

Keywords:
Floristics
niche analysis
Virgina mallow
Ripariosida hermaphrodita.

Presentation Type: Poster
Session: P, Floristics & Taxonomy Posters
Location: Virtual/Virtual
Date: Wednesday, July 29th, 2020
Time: 5:00 PM Time and date to be determined
Number: PFT004
Abstract ID:375
Candidate for Awards:None