Introduction to Ash: The branches of Ash are opposite and have four edges; odd-numbered pinnate leaves, 7-11 egg-shaped oblong leaflets, wedge-shaped base, asymmetrical, serrated edges, lower surface There are dense yellow-brown hairs along the veins and the base of the leaflets, and the leaf rachis is slightly winged; the panicle is axillary, dioecious, and blooms in summer.