• Ithaca: Liberty Hide Bailey Hortorium, Cornell University, June 19-20, 1987
• Miami: Fairchild Tropical Garden, 20-21 October 1995
• New York Botanical Garden, 18-20 June 1997
  Memoirs: A. Henderson & F. Borchsenius  (eds.). 1998. Variation, evolution, and classification of palms. New York Botanical Garden, New York.
• The Linnean Society of London and the Royal Botanic Gardens, Kew, 6-8 April 2005.
  Memoirs: Botanical Journal of the Linnean Society vol. 151, 2006..
• Montpellier, France, 4-7 June 2010.
  Memoirs: Annals of Botany 108 (8), 2011.
• Montenegro, Quindío, Colombia, June 22-26 - 2015
  Memoirs: Botanical Journal of the Linnean Society 182 (2) - 2016