Vascular plant extinction in the continental United States and Canada

Abstract

Extinction rates are expected to increase during the Anthropocene. Current extinction rates of plants and many animals remain unknown. We quantified extinctions among the vascular flora of the continental United States and Canada since European settlement. We compiled data on apparently extinct species by querying plant conservation databases, searching the literature, and vetting the resulting list with botanical experts. Because taxonomic opinion varies widely, we developed an index of taxonomic uncertainty (ITU). The ITU ranges from A to F, with A indicating unanimous taxonomic recognition and F indicating taxonomic recognition by only a single author. The ITU allowed us to rigorously evaluate extinction rates. Our data suggest that 51 species and 14 infraspecific taxa, representing 33 families and 49 genera of vascular plants, have become extinct in our study area since European settlement. Seven of these taxa exist in cultivation but are extinct in the wild. Most extinctions occurred in the west, but this outcome may reflect the timing of botanical exploration relative to settlement. Sixty‐four percent of extinct plants were single‐site endemics, and many occurred outside recognized biodiversity hotspots. Given the paucity of plant surveys in many areas, particularly prior to European settlement, the actual extinction rate of vascular plants is undoubtedly much higher than indicated here.

Factors determining the distribution of orchids – a review with examples from the Czech Republic

“…Most species of orchids are threatened in the wild (Cribb et al 2003) and are disappearing from their natural habitats worldwide (Cribb et al 2003;Knapp et al 2020;Wagensommer et al 2020). In Europe, all orchids are terrestrial and can be found in almost all habitats (Hágsater and Dumont 1996;Delforge 2006;Štípková et al 2017).…”

“…There are many publications on the distribution of orchids worldwide, which indicate that both professionals and the lay public are interested in orchids (e.g. Millar 1978;Seidenfaden and Wood 1992;Bose et al 1999;Dykyjová 2003;Vlčko et al 2003;Jersáková and Kindlmann 2004;Průša 2005;Averyanov et al 2015;Antonopoulos and Tsiftsis 2017;Grulich 2017;Tsiftsis and Antonopoulos 2017;Kühn et al 2019;Knapp et al 2020;Wagensommer et al 2020 and many others). Unfortunately, the family Orchidaceae is one of the most threatened plant families with a high risk of species extinction (Swarts and Dixon 2009).…”

The growing and vital role of botanical gardens in climate change research

“…As the climate changes, botanical gardens play a key role in preserving living collections and seed banks to store and maintain rare plants, for later use in restorations and recovery in the wild (Schulman & Lehvävirta, 2011; Smith et al ., 2019; Knapp et al ., 2021). At an international level, these activities are coordinated by Botanic Gardens Conservation International (http://www.bgci.org).…”

Orchid Extinction over the Last 150 Years in the Czech Republic

“…One of the most important issues of modern conservation biology is to understand temporal changes in the distribution and abundance of various species [1]. During recent decades, the human impact on natural resources and habitats has caused a dramatically large extinction rate and a decline in the number of sites suitable for many plants and animals [2][3][4][5][6][7], with habitat loss and fragmentation being the most important factors [2,3]. Mankind has had a very marked effect on Europe, especially its rapid industrial development in recent centuries, which has resulted in a highly fragmented and degraded landscape [8].…”

“…With approximately 28,500 species [21], Orchidaceae is one of the most diverse and widespread families of flowering plant [18]. Unfortunately, most species of orchids are threatened in the wild [22] and are disappearing from their natural habitats worldwide [7,[22][23][24]. In Europe, the main reasons for this dramatic decline are habitat loss, eutrophication and fragmentation [12,23,[25][26][27][28].…”