The Snowdonia Hawkweed (Hieracium snowdoniense) is one of the world's rarest plants with just one surviving specimen remaining, endemic to Snowdonia, North Wales. It was first discovered in 1892, and has only been recorded from 7 mountain ledges around Snowdonia since then. It was rediscovered in 2002 after 35 years when it was thought to be extinct. The hawkweed forms a rosette of delicate leaves which narrow towards the base. A slender stem carries a bundle of deep golden-yellow flowers - it can grow up to 30cm in height. Very little is known about the ecology of this plant, however, like all hawkweeds, it is a perennial species which may fruit irregularly. It flowers in July, reproduces asexually and disperses its seeds in the wind. The species is thought to be threatened by overgrazing, particularly the massive increase of sheep grazing in Wales. Sheep find hawkweeds extremely appetising, therefore they have grazed Snowdonia hawkweed to extinction in certain areas. Another cause of decline for this species is the increase of acid rain, causing soil acidification.