of the type. There are three possibilities for the presence of H. canadense in Europe. First, the plant could be introduced by human means. This is highly improbable, with it being unlikely that any European gardener would cultivate the plant and unlikely that any American troops could transport the plant, though that American hypothesis has been supposed. Second, the plant could have been transported to Ireland by natural means, most likely being carried on the feet of the Greenland white-fronted goose if by any bird. The goose breeds in Greenland and winters in North America or Ireland, but this hypothesis can only be considered if H. canadense is discovered in Greenland. The third possibility is that the plant is relict in Europe, supported by the fact that several other species considered relict have similar geographic distributions. The plant's occurrence in Newfoundland gives credence to its hardiness, suggesting that it could have withstood the latest glaciation. Najas flexilis is similar in hardiness and survived the last glaciation as fossil evidence shows. The attempted creation of the Corrib-Mask Canal lowered water levels in the herb's Irish area, and if the plant was underwater before then, the relict hypothesis would be disproven. An 1841 map shows that the distribution of H. canadense stops short of the lakeshore by . However, the plant clearly occurs below an older shore line of uncertain age; the shore line is certainly post-glacial, but it may be old enough for the plant to migrate down to its current occurrence. The abundance and conspicuousness of the plant opposes this theory, as in the 1950s a few plants were discovered simultaneously in France and Ireland, but more recently the plants are quite abundant, suggesting more recent naturalization of the herb. The majority of evidence is in favor of the relict hypothesis, but future spreading or lack thereof of the plant will better suggest recent introduction or the growth of an autochthon. Habitat Hypericum canadense occurs in wet or dry soils in sandy ditches and clearings, road verges, pastures, boggy or peaty regions, gravelly beaches, and occasionally in woodlands. It is considered a facultative wetland plant in the United States, meaning that it usually occurs in wetlands, but may also occur in non-wetlands, typically in areas where the soil surface is flooded at least seasonally. In North Carolina, the herb occurs at elevations as high as . In the Chicago area,