Opuntia humifusa sensu lato, one of the most wide-ranging cactus species in North America, was first documented at The Sands in Seabrook, New Hampshire in 2011. More than 75 stems grow in a 1.5 m² area at the north end of The Sands on the upper slopes of a small dune. Although the Opuntia population in New Hampshire fits the physiological profile and broad habitat affinity of the species, it was initially unknown whether the population was native or naturalized. Determination of its nativity status is critical in evaluating the conservation status of this species in the state. The Natural Heritage network views naturally occurring populations as having inherently higher conservation value than either nonnative species or introduced populations of native species. After investigating the site history at The Sands and the natural history of O. humifusa, the New Hampshire Natural Heritage Bureau concluded that the population was very likely a recently naturalized exotic with low conservation status in the state.