Korean ash is native to ASIA-TEMPERATE
Russian Far East: Russian Federation - Primorye, Sakhalin; China; Eastern Asia: Korea; ASIA-TROPICAL: Indo-China: Vietnam 
Leaflets 3-7, terminal leaflet broadly ovate to elliptic, sometimes ± lanceolate, (4-)5-9(-12) × (2.5-)3.5-5(-7) cm, villous to tomentose beside basal part of midrib abaxially, sometimes brownish, margin crenate-serrate, apex short acuminate to acuminate or caudate; primary veins (5 or)6-9 on each side of midrib. Samara narrowly to very narrowly spatulate, 2.5-4 cm × 4.5-7 mm. Fl. Apr-May, fr. Sep-Oct.
Grows on slopes, along rivers, roadsides; 0-1500 m. Gansu, Hebei, Heilongjiang, Henan, Jilin, Liaoning, Shaanxi, Shandong, Shanxi [Japan, Korea, Russia]. The wood is used for cabinet making." -- Flora of China 
Family Oleaceae - Olive, Ash, Lilac and Privet
The olive family contains 25 genera and over 500 species of flowering plants. Most species are native to temperate and tropical regions of the Northern Hemisphere. The best known trees of this family are olive and ash, while the most familiar shrubs are privet, lilac, and golden bell (Forsythia), all popular ornamental plants.
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