Soda inermis, the opposite-leaved saltwort, oppositeleaf Russian thistle, or barilla plant, is a small, annual, succulent shrub that is native to the Mediterranean Basin. It is a halophyte that typically grows in coastal regions and can be irrigated with salt water. The plant was previously classified as Salsola soda, and many of the sources for this article used that designation.

Salsola is a genus of the subfamily Salsoloideae in the family Amaranthaceae. The genus sensu stricto is distributed in central and southwestern Asia, North Africa, and the Mediterranean. A common name of various members of this genus and related genera is saltwort, for their salt tolerance. The genus name Salsola is from the Latin salsus, meaning "salty".