Syringa reticulata (Japanese Tree Lilac; Chinese: 暴马丁香 bao ma ding xiang; Japanese: ハシドイ hashidoi) is a species of Lilac, native to eastern Asia, in northern Japan (mainly Hokkaidō), northern China, Korea, and far southeastern Russia.
It is a deciduous small tree growing to a height of 12 m, rarely to 15 m, with a trunk up to 30 cm (rarely 40 cm) diameter; it is the largest species of lilac, and the only one that regularly makes a small tree rather than a shrub. The leaves are elliptic-acute, 2.5–15 cm long and 1–8 cm broad, with an entire margin, and a roughish texture with slightly impressed veins. The flowers are white or creamy-white, the corolla with a tubular base to 4–6 mm long and a four-lobed apex 3–6 mm across, and a strong fragrance; they are produced in broad panicles 5–30 cm long and 3–20 cm broad in early summer. The fruit is a dry, smooth brown capsule 15–25 mm long, splitting in two to release the two winged seeds.
There are three subspecies:
It is grown as an ornamental tree in Europe and North America.