Tree of Cheem

The Forest of Cheem are a group of intelligent, humanoid, trees, descended from the rain forests of Earth. The trees of Cheem look like humanoids with large, intricate heads and wood-like skin. They have retractable vines on their arms, but they aren't supposed to show them in public. The trees of Cheem are made of wood and are therefore highly flammable.

According to the Doctor, they are of huge financial importance due to their land holdings and forests on various planets; and they have "roots" everywhere. Because of this, several trees of Cheem were found on Platform One in 5,000,000,000 to watch the destruction of Earth. The group of Trees seen on Platform One was led by Jabe Ceth Ceth Jafe and also included Coffa and Lute.

The Forest of Cheem do not understand technology, referring to computers as "metal minds" or "metal machines", however they are known to use it. They were also aware of the Time Lords and their fate in the Time War. (DW: The End of the World)

As one of the higher species who were aware of the course of the war and its history-changing effects and also states that they were mortified by the bloodshed. (DWA: Doctor Who Annual 2006)

It was the genetic engineers, the Brothers of Hame who brought a 500 x 300 mile plot of trees from the rain forests on Earth. They took it to their home world in the Panjassic Asteroid Field where the trees' evolution was accelerated from a billion years to just three years. Collectively the Forest of Cheem turned against their creators and fled into space in spaceships made from bark. 5000 years later the Forest of Cheem were considered to be part of the Higher Species and witness to the last great Time War.(REF: Doctor Who DVD Files & Doctor Who: Monsters and Villains)