One-fifth of Plants Face Extinction

A report called State of the World's Plants by the Royal Botanic Gardens at Kew finds 391,000 known species of plants. Up to 21 percent of all plant species are threatened.

The biggest factors threatening plant species with extinction are the destruction of habitats for farming (31%) - such as palm oil production and cattle ranching, deforestation for timber (21%) and construction of buildings and infrastructure (13%). Climate change is currently a smaller factor - 4% - but is likely to grow.