Grand Arboretum

The  was an organisation dedicated to interstellar botany across the universe. It was responsible for the oversight of World Trees among other duties.

History
The Grand Arboretum was ruled by a Chief Gardener, who by the 21st century was an Aplan.

Despite World Trees requiring protection due to being large and fast-growing enough to overwhelm some planets, they once lost one seed, which floated through space for over one thousand years before landing in Nora Wicker's garden on 19 August 1987. When the Eleventh Doctor protected it by encasing it in a Time Bubble, he contacted the Grand Arboretum who promised to collect it when a suitable host planet was found, but admitted that could take anywhere between several weeks or several thousand years. They promised that "heads will roll" due to their oversight, but the Doctor considered that an empty promise because of Aplans having two heads. (AUDIO: The World Tree)