洋 'foreign' marks it as the introduced species, distinct from the native
槐树 (huáishù, Sophora japonica, Chinese scholar tree). Robinia was brought from North America in the late 19th century and naturalized rapidly across northern China. Its springtime blossoms are eaten — steamed with flour for
槐花饭 (huáihuāfàn) or fried as
槐花饼 — and prized by beekeepers for
槐花蜜 (huáihuāmì, 'locust honey'), one of China's most popular monofloral honeys.