A bristlecone pine can refer to one of three species of pine trees (family Pinaceae, genus Pinus, subsection Balfourianae). All three species are long-lived and highly resilient to harsh weather and bad soils. One of the three species, Pinus longaeva, is among the longest-lived life forms on Earth. The oldest Pinus longaeva is more than 5,000 years old, making it the oldest known individual of any species.