An ex situ (offsite) collection of seeds, plant tissues, or whole plants that supports species’ survival and reduces the extinction risk of globally and/or regionally rare species. A conservation collection has accurate records of provenance, maternal lines differentiated, and diverse genetic representation of a species’ wild populations. To be most useful for species survival in the wild, a conservation collection should have depth, meaning that it contains seeds, tissues or whole plants of at least 50 unrelated mother plants, and breadth, meaning it consists of accessions from multiple populations across the range of the species. Conservation collections should have tests of initial germination and viability, cultivation protocols developed, and periodic testing of long-term viability. A conservation collection differs from a horticultural collection, which may have few genetically unique individuals, or is solely comprised of unusual appearing forms.