Dracaena draco - This beautiful tree is native to Socotra (an island in the Arabian sea, part of Yemen). It is 6-9m tall and has trunks that are long and slender, with prickly leaves. The flowers are green and white and have a sweet smell. The orange brown berries are a little smaller than a cherry and covered in a red, resinous substance. The dragon tree has mythical origins: for his 11th labour, Hercules had to bring back golden apples from the garden of Hespérides, which was guarded by a hundred-headed dragon. Hercules killed it and blood flowed out over the land, which began to sprout dragon trees. The tree oozes "dragon's blood" - a red sap - when cut. The trees only flower every 15 years and the oldest dragon tree is thought to be more than 650 years old. The red sap of this species is used as colouring for varnishes, toothpastes and plasters. There are around 300 trees remaining - the extinction of a bird that assisted in the germination of the seeds has resulted in a sharp decline in number of the species. Therefore, the seeds can no longer germinate without human manipulation. Serious threats include the introduced rats that feed on the seeds and grazing animals that feed on seedlings, preventing growth.