Acer distylum Sieb. & Zucc.

Rare in cultivation as it is in the wild (van Gelderen, de Jong & Oterdoom 1994), Acer distylum was introduced to cultivation in Britain by Charles Maries for the Veitch Nurseries in 1879 (Edwards & Marshall 2019; le Hardÿ de Beaulieu 2003). It became commercially available in North America some eighty or so years later, during the 1960s (Jacobson 1996).

An elegant species of slow steady growth, Acer distylum prefers rich, lime-free soils. Tolerant of heavier soils, it does not like to be dried out. Like many maples, it benefits from some shade (Edwards & Marshall 2019; le Hardÿ de Beaulieu 2003) and makes an excellent choice for the woodland garden. Jacobson (1996, p.18) describes its autumn colour as “ho-hum yellow or poor dull brown”, but in good growing conditions it performs well, turning rich yellow to gold.

The common names reflect its heart-shaped leaves that recall those of some Tilia species. The Japanese name, maruba kaede, translates as “round-leaved maple”. The leaves can be confused with some forms of A. davidii, though that species is easily distinguished by its stipitate buds and striated bark. A. distylum is sometimes likened in leaf to Davidia involucrata, confusion with which, like species of Tilia, is quickly expelled by its opposite branching. The specific epithet distylum refers to the bifurcating styles of the female flowers, a character possessed by all maples.

Little wild origin material is represented in collections. Plants are invariably grown from seed, though successful propagation can be tricky. Like the related Acer nipponicum – but unlike many other maples – the species appears incompatible with being grafted onto unrelated rootstocks.

A tree from Maries’ 1879 introduction, grown at Veitch’s Coombe Wood nursery in Surrey, established as a reliable seed producer from an early age had attained 9 m in 50 years (Gregory 1995), though apparently since lost. The current UK and Irish Champion is a tree of 10.4 m tall at Birr Castle, Offaly, Ireland measured in 2024 (The Tree Register 2025). A tree of 10 m measured in 2024 is at Carberry Tower, Musselburgh, Scotland (The Tree Register 2025). A plant grown from seed collected in September 2003 under EJE 191 at 750 m asl in Adatera Forest Park, Fukushima Prefecture, Honshu, grows at Benmore Botanic Garden, Argyll (Royal Botanic Garden Edinburgh 2023 onwards). Trees growing at the Von Gimborn Arboretum, the Netherlands are the source of three young plants added to the Westonbirt collection in 2018. Growing steadily, these have attained 2 m by January 2026 (pers. obs.). Specimens at Wespelaar, Belgium, grown from material gathered by Philippe de Spoelberch and accessioned in 2012 are of similar vigour. Examples at the University of British Columbia Botanical Garden were grown from seed from a tree at the University of Washington Arboretum. The parent plant is perhaps the specimen described by Jacobson (1996, p.18) as being like ” a droopy, gaunt dove tree (Davidia involucrata)”.

A single cultivar is recorded from Japan (Vertrees & Gregory 2009).