According to the International Union for the Conservation of Nature and Natural Resources (IUCN), 8,321 species of plants are threatened or critically endangered worldwide. In some cases, only one or two examples of the species are known in the wild. In many cases, pressure from introduced species and human population pressure is the primary driving force behind the plants endangered status.
The Darwinia chapmaniana is native to Australia. This native plant is on the critically endangered list because of Australian land clearing and grazing practices.
The Acalypha wigginsii, known as the Wiggins's Acalypha, is native to the Galapagos Islands. The Wiggin's Acalypha is endangered because of a critically small habitat, the peak of Cerro Crocker, combined with human construction and activity, including trampling.
The Symphyotrichum georgianum, also known as the Georgia Aster, is critically endangered because of a relatively small native plant area combined with loss of land and habitat. The Georgia Aster is native to the southeastern United States. Initially, only 100 populations were known, but in recent years those populations have dropped by over 1/3.
The Orbea paradoxa is a South African plant in the Stapeliad family. Orbea paradoxa are virtually unknown in the wild after their small habitat was destroyed as part of a South African dam construction project.
The Calandrinia gapagosa is endangered due to a small native area in the Galapagos islands and the effects of grazing from human introduced species like donkeys and goats. Also known as the Galapagos rock-purslane, the current known populations are protected from animals by a fence.
The Astrophytum asterias, also known as the Star Cactus, is native to southern Texas. Te Star Cactus is on the endangered list because of over collection, over use of herbicides, and urban sprawl.
Hibiscus insularis, or Phillip Island Hibiscus, is one of the most rare plants in the world. In the wild, it currently only exists in in two very small clumps in the wild. Phillip Island Hibiscus is native to Phillip Island, Australia. This plant is primarily threatened by grazing by feral pigs, goats, and rabbits.
The Linum cratericola, also known as Floreana Flax, is native to the Galapagos. Although threatened by goat grazing and grazing from other introduced species, dry periods have recently increased grazing pressure and pressure on this species.