Amyris elemifera

Amyris elemifera, (PROSE: History of the House) also known as North American torchwood, (PROSE: The Time Travellers' Almanac) was a type of large tree found in tropical areas such as Florida. Its oils were belived to have excellent medicinal qualities. (PROSE: History of the House) It had pale green leaves. (PROSE: Another Life)

The eccentric Sir George MacLeish had a number of these trees shipped over to Scotland and use their wood to rebuild the Great Staircase at Torchwood House. (PROSE: History of the House)

Guy Wildman had Amyris elemifera in his apartment. When Torchwood Three investigated the apartment, Sandra Applegate, using the alias Betty Jenkins, lied that she was a neighbour feeding his plants. (PROSE: Another Life)

Behind the scenes
In the real world, common names for amyris elemifera fittingly include "sea torchwood" and "smooth torchwood".