Platanthera chapmanii

Platanthera chapmanii is a perennial herb in open, wet pine flatwoods, barrens, and savannas, sometimes also in open wet meadows, bogs, and hillside seeps, that is endemic to the southeastern United States where it occurs in northern Florida and adjacent southeastern Georgia as well as in southeastern Texas. While there are an estimated 74 occurrences with a total population size of approximately 5000 individuals, many sites have fewer than twenty plants. Most populations occur in northern Florida, where many can be found on protected lands in the Apalachicola and Osceola National Forests as well as in Saint Marks National Wildlife Refuge. The species' range extent in Texas has declined long-term, and populations in Georgia are mostly small and located on rights-of-way. Threats include development, rights-of-way maintenance activities, fire suppression, alterations to hydrology, forestry practices, recreational activities, and invasive species.

Platanthera chapmanii is endemic to the southeastern United States where it occurs in northern Florida (eleven counties) and adjacent southeastern Georgia as well as in southeastern Texas (four counties) (FNA 2002, Brown 2004, Weakley and the Southeastern Flora Team 2025). Range extent was estimated to be approximately 114,000 square kilometers using herbarium specimens and NatureServe Network occurrence data documented between 1994 and 2025 (GBIF 2025, NatureServe 2025, RARECAT 2025, SEINet 2025).

By applying a 1 km separation distance to herbarium specimens and NatureServe Network occurrence data documented between 1994 and 2025, it is estimated that there are 74 occurrences rangewide (GBIF 2025, NatureServe 2025, RARECAT 2025, SEINet 2025).

This species faces threats from habitat loss and degradation. Loss of habitat may be due to development, especially in Texas, or conversion of pine flatwoods to slash pine plantations. Intense site preparation for forestry management, including dozing, root raking, or chopping, have negative impacts on this species, exacerbated by canopy closure from planted pines (Chafin 2020).

The primary habitat degradation threats are fire suppression and rights-of-way maintenance. Fire suppression is likely to degrade existing habitat, increasing woody plant encroachment and possibly invasive species cover, resulting in the possible loss of populations (NatureServe 2025). Even where habitat is managed, burning may take place at less frequent intervals than what is ideal; these protected occurrences may also face threats from recreational activities (especially off-road vehicles) (Richards and Sharma 2014). At least forty occurrences, over half all known occurrences, are located within roadside or powerline rights-of-way, and threats to roadside sites include injury or destruction by mowing, herbicides, or crushing by heavy machinery (Richards and Sharma 2014). However, mowing outside the flowering period may be beneficial to reduce woody plant encroachment (NatureServe 2025). Additional habitat degradation threats include invasive species, such as feral hogs, Japanese climbing fern (Lygodium japonicum), and black titi (Cliftonia monophylla) (NatureServe 2025).

While evidence of poaching is lacking, it is a showy orchid species that could face threats from poaching.