Tievine (Ipomoea trichocarpa) belongs to Convolvulaceae (the Bindweed family). It is a perennial herb that is native to the southern United States; from North Calorina to Texas and Mexico. It is also naturalized in Japan, and distributed westward from Chubu district of Honshu to Shikoku and Kyushu. This herb is a vine and grows in grasslands, thickets or roadsides, and can reach about 4.5 m long. The leaf features have two types, trolobate and undivided. The funnel-shaped, 2.5-4 cm across flowers bloom from May to October. The corolla is pink with dark magenta throat.