Dioon edule, the chestnut dioon, is a cycad native to Mexico, also known as palma de la virgen. It belongs to the Zamiaceae plant family within the order Cycadales. The genus name "Dioon" means "two-egged", referring to the two ovules.
Dioon edule is a very adaptable plant to just about any soil except muddy, non-draining clay. It is long lived and slow growing and a plant with 30cm of stem can be quite old (20-40 or more years). Dioon edule grows in areas transitional between tropical deciduous forest and oak woodland, and in harsh, dry conditions in steep hillsides and cliffs on extremely steep slopes where the soils are skeletal and poor with few nutrients, in limestone, serpentine or in sandy soil, but they can also be found in more hospitable soils and shelter. Interestingly, Dioon edule specifically has the ability to contract its stem underground as it grows — thus maintaining relativity in the amount of trunk exposed. Cycads are among the oldest seed plants and even pre-date the dinosaurs.
