The Spontaneous Vascular Plant Flora of New York's Central Park¹¹ᵇ

This work details the spontaneous vascular plant flora of New York City's Central Park for the period 2013 to 2017. We divided the 341-ha (843-acre) park into 36 zones and used a modified timed-meander sampling method to collect herbarium specimens and silica-dried samples (for DNA analysis) of spontaneous, naturalized plants. We collected each new species until we ceased to find any species that had not been previously encountered in any zone. We collected 1,468 specimens, representing 438 species and two subspecific taxa from 262 genera and 89 families, and a number of cultivated species not analyzed is this work. We find that 45% of the flora are native (198 species) and 54% (240 species) are nonnative. Three species are of unknown native status (<1%). The largest families are Poaceae (56 species), Asteraceae (55), Rosaceae (27), Fabaceae (20), and Polygonaceae (17). The largest genera are Persicaria (8 species), Carex (7), Acer (7), Cyperus (6), Rubus (6), and Eragrostis (6). Seven species are ranked as rare, threatened, or endangered by New York Natural Heritage Program. Thirty-six species are listed as prohibited or regulated invasive species by New York State. Four species new for New York State were collected in Central Park during this study. We documented 76 additional species since the last inventory of 2007. The percentage of native species has increased by 5% since 2007. The data suggest that management efforts focused on controlling invasive species and planting and supporting native species have been effective. The spontaneous, naturalized flora is listed in Appendix I. Spontaneous plants that appear once or sporadically but do not persist without repeated introduction are listed as waifs in Appendix II. The species are listed with scientific and common name, native status in New York State, coefficient of conservatism, New York Natural Heritage Program rarity ranking (S1–S5), observed frequency in Central Park (rare, infrequent, and frequent), and observed species fecundity for Central Park (decreasing, stable, or increasing). All species reported are vouchered by herbarium specimens and silica-dried tissue samples at the New York Botanical Garden.