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 relative absence of 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 (Bean 1976)), 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 observed by JMG in 2005 it was c.10 m tall (25 cm dbh) with two more or less equal main stems from a fork at 3.5 m. The branches are spreading and slightly pendulous, bearing the dark green, three-pointed leaves as a light canopy. Plants propagated from this specimen 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.

The tallest example in the UK is a male specimen at the Sir Harold Hillier Gardens, Hampshire, measured at 11.7 m in 2021 (The Tree Register 2025). A smaller, male specimen growing at Batsford Arboretum, Gloucestershire, was measured at 8 m tall in 2014 (The Tree Register 2025). A female tree at 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, A. 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).