Daisy tree (Scalesia divisa)

Also known as: Scalesia
KingdomPlantae
PhylumTracheophyta
ClassMagnoliopsida
OrderAsterales
FamilyAsteraceae
GenusScalesia (1)
SizeMax height: 4 m (2)

The daisy tree is classified as Critically Endangered (CR) on the IUCN Red List (3).

Owing to their extensive evolutionary radiation in the Galapagos archipelago, the 15 species of daisy tree that comprise the genus Scalesia are often considered the plant equivalent of Darwin’s Finches (4) (5). Indeed, in reference to the Scalesia in ‘The Voyage of the Beagle’, Darwin himself refers to “a remarkable arborescent genus of the Compositae [now known as Asteraceae]” (6). The daisy trees evolved from a single ancestor of the daisy family, that reached the Galapagos Islands many millennia ago (4) (5) (7). Scalesia divisa typically grows as a bush, never exceeding four metres in height (1) (2). Its ovate, divided leaves are arranged oppositely, and its daisy like flower-heads are made up of 30 to 100 white flowers (2).

Scalesia divisa is endemic to the Galapagos Islands, where it is restricted to part of San Cristóbal Island (1) (2) (7).

Scalesia divisa is mainly found on open lava flows including low cliffs (7).

Very little is known about the biology of Scalesia divisa, but, in common with other species in the genus, it has dandelion-like seeds dispersed by the wind (8).

Since humans arrived on the Galapagos, dramatic ecological changes have been caused by agricultural activities, exploitation of native species, and the introduction of non-native animals and plants (7). Consequently, many species of Scalesia are now under significant threat of extinction. For Scalesia divisa, the greatest concern is introduced goats, which have caused extensive damage to the few remaining populations (1) (4).

Scientists at the Charles Darwin Research Station are involved in several projects to restore and preserve populations of Scalesia species, including those on San Cristóbal (4). The management priority on San Cristóbal is to eradicate the feral ungulates that are causing so much damage (7).

Further information on the conservation of the endemic flora and fauna of the Galapagos:

Authenticated (17/04/09) by Dr. Alan Tye, Chair, IUCN-SSC Galapagos Plant Specialist Group.

  1. Tye, A. (1/1/0001 12:00:00 AM) Galapagos species accounts. in: León-Yánez, S. (Ed.) Libro Rojo de las Plantas Endémicas del Ecuador. Second edition. Herbarium of the Pontificia Universidad Católica del Ecuador, Quito,.
  2. McMullen, C.K. (1999) Flowering Plants of the Galapagos. Cornell University Press, New York.
  3. IUCN Red List (March, 2011)
    http://www.iucnredlist.org/
  4. Charles Darwin Foundation. (2006) Charles Darwin Research Station Fact Sheet: Scalesia trees & shrubs. Charles Darwin Foundation for the Galapagos Islands (AISBL), Galapagos, Ecuador. Available at:
    http://www.darwinfoundation.org/files/species/pdf/scalesia-en.pdf
  5. Tye, A. (2009) Pers. comm.
  6. Darwin, C.R. (1845) Journal of researches into the natural history and geology of the countries visited during the voyage of H.M.S. Beagle round the world, under the Command of Capt. Fitz Roy, R.N. 2nd edition. John Murray, London. Available at:
    http://darwin-online.org.uk
  7. Tye, A. (2003) Plant research for conservation in Galapagos. Report for the years 1998–2003. Charles Darwin Foundation for the Galapagos Islands, Galapagos, Ecuador.
  8. Colinvaux, P.A. (2007) Amazon Expeditions: My Quest for the Ice-Age Equator. Yale University Press, New Haven and London.