Small tree, ultimate height unknown. Branchlets covered with white pubescence, later glabrous. Leaves deciduous, 2.3–5.5 × 3–8 cm, palmately five-lobed to nine-lobed up to half-way to the base, both surfaces covered with rough, white hairs, margins sharply double-serrate, lobe apex acuminate; petiole 1.5–5 cm long, pubescent. Inflorescence corymbose, densely pubescent. Flowers small, staminate or hermaphrodite; sepals five, purplish, ovate to lanceolate, petals four, white, ovate to orbicular, stamens four. Samaras 2–3 cm long, yellowish brown when mature, wings spreading obtusely. Flowering April, fruiting September (Taiwan). Van Gelderen et al. 1994, Xu et al. 2008. Distribution TAIWAN. Habitat Deciduous forest between 1000 and 2000 m asl. USDA Hardiness Zone 6. Conservation status Vulnerable, due to overharvesting and poor regeneration. Cross-reference K90 (as A. palmatum var. pubescens). Taxonomic note Acer duplicatoserratum var. chinense C.S. Chang occurs in mainland China (Anhui, Fujian, Guizhou, southern Henan, Hubei, Hunan, Jiangsu, Jiangxi, Shandong, Zhejiang); the petioles are pubescent when young, but later become glabrous (van Gelderen et al. 1994, Xu et al. 2008).
A member of the Acer palmatum complex, A. duplicatoserratum is distinguished from its relatives by its pubescent shoots and leaves, but otherwise looks very similar to A. palmatum. It is rare both in the wild and in cultivation, although it ought not to be particularly challenging to grow. Trees from both Taiwan (from Edward Needham’s 1998 collection EN 0036) and Zhejiang in mainland China (SBG 303, 1996) are cultivated at Tregrehan, where they have been slow-growing (T. Hudson, pers. comm. 2007). There are some differences between these two stocks, but this needs investigation as the trees mature.