Tree (rarely a shrub) to 20 m, dbh 40 cm. Branchlets brown with some brown pubescence or glabrous; at maturity, bark grey. Stipules lanceolate, pubescent, 0.3–0.5 cm long; withering early. Leaves deciduous, 3–10 × 3.5–6 cm, elliptical to ovate, papery, upper surface with inconspicuous pubescence when young, lower surface with pubescence limited to the veins or in tufts in the vein axils, three to four secondary veins on each side of the midvein, margins subentire to crenate, apex acute to acuminate; petiole furrowed, 0.3–1 cm long, with pubescence above. Flowers arranged in densely clustered cymes in leaf axils and at base of young stems. Infructescences unbranched, one (to three) per leaf axil; stout, pubescent, 0.4–1 cm long. Fruit globose, 0.5–0.8 cm diameter, green to red to black. Flowering March to April, fruiting September to October (China). Fu et al. 2003. Distribution CHINA: Anhui, Fujian, Gansu, Guangdong, Guizhou, Henan, Jiangsu, Jiangxi, northeast Shandong, Sichuan, Zhejiang; JAPAN: Honshu, Kyushu, Shikoku; NORTH KOREA (?); SOUTH KOREA ; TAIWAN. Habitat Very common in a variety of habitats, from hills to lowlands and roadsides, between 100 and 1500 m asl. USDA Hardiness Zone 6–7. Conservation status Not evaluated. Illustration Valder 1999, Fu et al. 2003, Wharton et al. 2005; NT227, NT230, NT231. Cross-reference K308. Taxonomic note Celtis sinensis var. japonica (Planch.) Nakai from Japan and possibly Korea is recognised by several authors (for example, Ohwi 1965), though there appear to be no significant differences from the type variety.
Celtis sinensis is a good example of a tree thriving where summers are hot and failing to perform well where they are cool. At Kew there is a specimen from BECX 255, collected in South Korea in 1982, that is now only 3 m tall (but some 5.5 m wide) – although TROBI records an 11 m tree at Kew grown from seed collected in 1976. In North America, however, it responds to the extra warmth and grows very quickly into a large and stately tree. There are magnificent specimens both at Quarryhill (from SOJA 428, collected in Honshu in 1989, planted in 1991) and at the JC Raulston Arboretum (provenance unrecorded). Even with infestations of tent caterpillars, the largest Quarryhill specimen was over 10 m tall, 39 cm dbh in 2004, and looked extremely happy. In the very different conditions of Raleigh it was equally high but with lesser girth, forming a wide, shade-creating canopy of very dark leaves. At the US National Arboretum, a tree of Japanese origin has also grown very fast but has a thinner canopy. Celtis sinensis has long been valued in Chinese horticulture for its shade-giving, but also for its longevity and tolerance of poor conditions (Valder 1999), and it can become a large and characterful tree.
The ‘catch’ with this species is that it has become a seriously invasive pest in the damper parts of Australia; it is a declared ‘noxious weed’ in New South Wales, where it was introduced ‘about 50 years ago’ as an ornamental (Ensbey 2002). It is also self-sowing at Quarryhill, and should perhaps be monitored for potential invasiveness in the southern parts of the United States.
Celtis sinensis is often used as a bonsai subject, and there is a lovely weeping clone ‘Green Cascade’ which deserves wide planting. It was selected from a batch of seedlings grown from seed collected from a famous pendulous specimen at Suwa Jinja shrine in the village of Kamiyamaguchimura in the Nagano Prefecture, Japan, by Cliff Parks of the Camellia Forest Nursery in Chapel Hill, North Carolina in 1983 (Creech 2003). Unsupported, ‘Green Cascade’ will sprawl on the ground, but it can be trained on a pergola into a very appealing curtain.