Rosa rugosa
The highway is then carried south across the Tsugaru Strait via the Tsugaru Kaikyō Ferry to Ōma on the northern tip of Aomori Prefecture's Shimokita Peninsula. From the route's northern terminus in Hakodate to Ōma, National Route 338 runs concurrent with National Route 279; however, in Ōma, National Route 338 leaves the concurrency, traveling south while Route 279 heads southeast towards Mutsu. In Aomori, Route 279 is known as the Mutsu Hamanasu Line, named after the "hamanasu", known in English as the "Rosa rugosa", a shrub-like rose that grows on the beaches of Japan.