| Author | L. | |
| Distribution | Recorded only from the Outer Banks of Dare County, in Nags Head village in 1950-1974. In the 1970s it was numerous at the Sea Oatel. In 2021, a population was documented on iNaturalist as "persistent" in Nags Head.
Native of Europe; in N.A. Ont., NY, NJ, VA, NC. | |
| Abundance | Very rare. The population was considered "abundant" in the 1950s and must have been common in the 1970s judging from the number of specimens made. There are no other collections elsewhere of escaped individuals. | |
| Habitat | Maritime dunes. | |
| Phenology | Flowering and fruiting July-August. | |
| Identification | Seaside Eryngo or Sea Holly is hard to mistake, with its stems, broad leaves, and bracts all glaucous. The flowers are bright lavender-blue. The leaves and bracts have sharp marginal spines and recall holly leaves. It grows to 1-2 feet tall but is often sprawling, wider than tall. Eryngium aquaticum also is glaucous, but its leaves are much narrower and spineless. | |
| Taxonomic Comments | | |
| Other Common Name(s) | Sea Holly | |
| State Rank | SE | |
| Global Rank | GNR | |
| State Status | | |
| US Status | | |
| USACE-agcp | | |
| USACE-emp | | |
