Acer sinopurpurascens W.C. Cheng

Although an attractive and elegant tree that deserves widespread cultivation, Acer sinopurpurascens is extremely rare in horticulture due to difficulties in its propagation. The species is dioecious and specimens are widely separated, eliminating potential for cross-pollination. Possibilities for grafting have generally been considered limited by the paucity of appropriate rootstock material, though offspring from seedling-producing Acer sterculiaceum provide opportunity for experimentation. While not seed-producing, the red flowers, appearing early in the year and on young plants, are spectacular (le Hardÿ de Beaulieu 2003).

Details of the species’ introduction appear obscure. Harris (2000) states a date of 1980 (via material sent from China to his own collection at Mallet Court (Clarke 1988), while Edwards & Marshall (2019) list it as 1964, a date consistent with the acquisition of a male tree at Arboretum Trompenburg, The Netherlands, obtained from Dr Illa Martin from Germany as part of a dispersal of stock following the death of her husband. Its ultimate origin is however unknown (van Hoey Smith 2001). When John Grimshaw observed it in 2005 during research for New Trees it was c. 10 m tall and 25 cm dbh with two more or less equal main stems from a fork at 3.5 m (Grimshaw & Bayton 2009). The branches are spreading and slightly pendulous, bearing the dark green, three-pointed leaves as a light canopy. Plants propagated from this specimen (presumably by grafting) have been distributed by Plantentuin Esveld, but overall this is a good example of a case where a concerted conservation attempt is needed to propagate a rare and recalcitrant species to increase its genetic diversity in cultivation.

The tallest Acer sinopurpurascens in the UK is a tree at the Sir Harold Hillier Gardens, Hampshire, measured at 11.7 m in 2021 (The Tree Register 2025). Noted as male by Grimshaw & Bayton (2009), the tree produces fruits, as illustrated by a specimen collected by Jan De Langhe in 2024 (below). A smaller male growing at Batsford Arboretum, Gloucestershire, was measured at 8 m tall in 2014 (The Tree Register 2025), while a female tree in the Valley Gardens, Windsor, mentioned and illustrated by van Gelderen & van Gelderen (1999), was measured at 5.5 m tall in 2021 (The Tree Register 2025). The northernmost specimen recorded on The Tree Register (2025) is at Blagdon Hall, Northumberland, measured at 5 m tall in 2013. In Poland, a female tree derived from Shanghai Botanic Garden seed has been hardy since 1981 at Rogów and has reached over 7 m – but again, being a solitary specimen, it does not set viable seed (Tumilowicz 2002). The species appears to be unknown in North American collections, but its hardiness should be useful there.

Like some (but not all) members of Section Lithocarpa, Acer sinopurpurascens has lactiferous sap. In leaf it is most likely to be confused with A. tsinglingense, which also has lactiferous sap, but the flowers of that species are yellowish green rather than red or purple (Xu et al. 2008; Aiello & Crowley 2021).