Tree 20–25 m. Bark brown. Branchlets glabrous, remaining green for several years. Leaves deciduous, 5–15 cm across, orbicular, palmately three- to five-lobed, lobes shallow, both surfaces glabrous, margins subentire to sinuate; petiole 1–4 cm long, slender, exudes milky sap when broken. Inflorescence not seen. Samaras ~4 cm long, wings diverging at 45º; nutlets striped or veined. Van Gelderen et al. 1994, Rushforth 1995. Distribution VIETNAM. Habitat Broadleaved, mesic forest between 1600 and 1800 m asl. USDA Hardiness Zone 8–9. Conservation status Not evaluated. Illustration Rushforth 1995. Taxonomic note Xu et al. (2008) treat this taxon as a synonym of A. amplum subsp. bodinieri (H. Lév.) Y.S. Chen.
Acer chapaense seems first to have been collected by Bob Cherry and Keith Rushforth during an expedition to Vietnam in 1992. It became established in Bob Cherry’s arboretum at Kulnura, New South Wales, whence seed from the cultivated trees has been distributed. Young plants from this source are growing well at Hergest Croft, and are now over 2 m tall, having survived the 2005–2006 winter without damage.
The whole plant (at least when young) has a resemblance to members of the A. campbellii group, but has milky sap and lacks serrated leaf margins. The leaves are leathery, with a faint velvety feel to the underside, and flush red-bronze. They persist on the tree for much of the winter, falling in January, not long before the new shoots break. In Vietnam it grows in wet forest with a number of broadleaved trees that are generally considered to be hardy, in the United Kingdom at least (Rushforth 1995), but it should probably be given a sheltered site in a moist fertile situation.