"Pinus orizabensis" is the most recent pinyon pine to be described, discovered by Dana K. Bailey in 1983 when examining an unusual pinyon cultivated at the Royal Botanic Gardens, Kew; it was found to match wild specimens from the Pico de Orizaba. At first it was described as a subspecies of Mexican pinyon, but further research by Bailey & Hawksworth and others has shown that it is better treated as a distinct species. Some botanists still include it in Mexican pinyon though, despite their occurring together in some sites without evidence of hybridisation. Orizaba pinyon shows better adaptation to rainy temperate climate like England than "Pinus cembroides" which grows in dryer habitats.