Salsola kali subsp. pontica
Ann. Missouri Bot. Gard. 83: 389. 1996.
Stems usually glabrous (var. glabra Forsskål), sometimes papillose to hispid (var. pontica). Perianth segments with obscure midvein and weak apex. Bracteoles connate at base, swollen.
Phenology: Flowering late summer–fall.
Habitat: Sea beaches, salt marshes, sandy places in coastal regions, occasionally in ruderal inland habitats
Elevation: 0-10 m
Introduced; Ala., Calif., Del., D.C., Fla., Ga., La., Md., Mass., Miss., N.J., N.Y., N.C., Oreg., S.C., Tex., Va., Mexico, Eurasia, n Africa.
In the past Salsola kali subsp. pontica has been known in European botanical literature under the misapplied names S. tragus Linnaeus and S. kali subsp. tragus (Linnaeus) elakovsky. According to V. P. Botschantzev (1974), S. kali subsp. pontica is conspecific with S. caroliniana Walter (type at BM), which seems to be the earliest valid name at the species rank. N. N. Tzvelev (1993) treated S. caroliniana as a synonym of S. tragus sensu stricto. In American literature, the names S. caroliniana and S. kali var. caroliniana were sometimes applied (or misapplied) to various other taxa of the S. kali aggregate.
In their secondary, synanthropic areas of distribution in North America both subspecies of S. kali are often represented by intermediate or deviant forms. They seem to be less morphologically and geographically separated from each other than in their native Eurasian areas. Some authors have doubted the occurrence of S. kali subsp. kali in North America (see discussion in Rilke 1999). When immature, subsp. pontica is almost indistinguishable from subsp. kali. More detailed studies using fruiting material may clarify the exact distribution of both subspecies in North America. Subspecies pontica is certainly the more southern taxon both in North America and Europe and seems to be the only race of S. kali occurring in littoral habitats from South Carolina to coastal Texas. It is also known from scattered localities northward of South Carolina. In Canada only subsp. kali seems to occur, being gradually replaced southward by subsp. pontica.