Acer circinatum Pursh

The leaf and fruit of Acer circinatum in High Beeches Garden, West Sussex, UK. July 2018. Image Ron Kemeny.

Fruiting specimen of Acer circinatum at Arboretum Het Leen Eeklo, Belgium (16 May 2007). Image © Jan De Langhe - Arboretum Wespelaar.

Leaves on Acer circinatum, the lamina 7-to 9-lobed with the base clearly cordate and the petiole glabrous (Arboretum Het Leen Eeklo, Belgium – 16 May 2007). Image © Jan De Langhe - Arboretum Wespelaar.

As a wild plant, the long whippy branches of Acer circinatum make tangled thickets in the understorey. It is rarely a shapely shrub! (Del Norte Co., CA; 6th June 2022) Image Julian Sutton.

A large and shapely Acer circinatum (since lost) at Biel in East Lothian, UK; May 2012. Image Owen Johnson.

The giant Sequoia sempervirens at the Ackers Memorial Grove near Welshpool in Powys have been underplanted by the Royal Forestry Society with Acer circinatum, to recreate a natural association in California. May 2009. Image Owen Johnson.

Acer circinatum in High Beeches Garden, West Sussex, UK. July 2018. At 7.6 m it is among the taller examples in Britain. Image Ron Kemeny.

Immature samaras of Acer circinatum (University of British Columbia Botanical Garden, Vancouver, June 2023). Image John Grimshaw.

Developing samaras contrasting nicely with the foliage of Acer circinatum (Yorkshire Arboretum, UK, June 2024). Image John Grimshaw.

Acer circinatum spreading its leaves to catch the sun (University of British Columbia Botanical Garden, Vancouver, June 2023). Image John Grimshaw.

As an understorey tree of often quite dark conifer forests Acer circinatum twists to place its branches in the maximum light possible (University of British Columbia Botanical Garden, Vancouver, June 2023). Image John Grimshaw.

'Baby Buttons'

Introduced by Buchholz Nursery, a round, small-leaved dwarf that originated as a witches’ broom, attaining little over half a metre in height and width in 10 years (Buchholz & Buchholz Nursery 2019).

'Burgundy Jewel'

A selection of small stature with purple red leaves which hold their colour throughout the season, particularly in full sun, before turning orange and red in autumn (Buchholz & Buchholz Nursery 2019).

Acer circinatum 'Burgundy Jewel' (Rhododendron Species Botanical Garden, Seattle, June 2023). Image John Grimshaw.

Acer circinatum 'Burgundy Jewel' (Rhododendron Species Botanical Garden, Seattle, June 2023). Image John Grimshaw.

'Del's Dwarf'

A dwarf clone introduced by Delbert L. Loucks of Eugene, Oregon, attaining little more than 1 m tall and wide in 20 years (Hatch 2021–2022). It has bronze new growth that turns green in summer, then yellow, red or orange in autumn (Hatch 2021–2022).

'Elegant'

A clone selected by Hubert Rhodes in Skagit Valley, British Columbia, around 1954, and named later at the Dominion Arboretum, Ottawa (Jacobson 1996). It has leaves that are somewhat more incised and smaller than is typical for the species (Jacobson 1996).

'Glen Del'

Selected at Del Lane’s County Nursery, Eugene, Oregon, in 1976, and introduced in 1982, ‘Glen Del’ has a compact, narrow, upright habit, with deeply cut, five-lobed leaves (Jacobson 1996). It was named after nurserymen Glen Handy and Delbert L. Loucks (Jacobson 1996).

'Hidden Valley'

A selection with a shrubby habit, carrying bright green leaves that turn pink or red in autumn, introduced by Miyama Asian Maple Nursery, California (Hatch 2021–2022).

'HSI2'

A strongly upright cultivar, growing twice as tall as it does wide (Dirr & Warren 2019). Selected by Heritage Seedlings, Oregon (Heritage Seedlings & Liners 2021), its narrow habit lends itself to use in small gardens, and it is further suggested for use as a small street tree in the Pacific Northwest (Dirr & Warren 2019).

'JFS-Purple'

More compact than typical for the species, with fresh foliage tinted bronze, becoming purple before turning orange and red in autumn (Dirr & Warren 2019). Discovered by J. Frank Schmidt III, and introduced by J. Frank Schmidt & Son Co. (Schmidt 2019).

'Little Gem'

A selection made from a witches’ broom discovered by Alleyne Cook in Stanley Park, Vancouver (Hatch 2021–2022). Its half-size leaves are green in summer, turning orange or red in autumn, often to good effect (Hatch 2021–2022).

'Lyn'

Grown from seed collected on Mount Hood, Oregon by Greg Morgenson of North Dakota, and named for his wife (Hatch 2021–2022). Considered hardier than many other selections, it reaches nearly 5 m tall with a broadly upright habit and was introduced by Iseli Nursery of Boring, Oregon (Hatch 2021–2022).

'Monroe'

A cut-leaved clone discovered by Dr Warner Monroe of Portland, Oregon, along the Mackenzie River around 65 miles east of Eugene (van Gelderen, de Jong & Oterdoom 1994; Jacobson 1996). Monroe layered a plant where the original was found, taking the resulting plant home in 1965 (van Gelderen, de Jong & Oterdoom 1994). A second layer was acquired by J.D. Vertrees in 1970, who then began propagating the plant via grafting onto Acer palmatum (van Gelderen, de Jong & Oterdoom 1994) and the selection was introduced commercially in 1977 (Jacobson 1996). It is now cultivated on both sides of the Atlantic. Individuals develop a rounded crown with somewhat weeping stems, and are usually wider than tall and rarely more than 3 m in height after 25 years (Justice, in prep.). Foliage is a dull green, finely sharp-toothed, though not particularly sun-tolerant (Justice, in prep.), and also suceptible to mildew (van Gelderen, de Jong & Oterdoom 1994)

The beautiful foliage of Acer circinatum 'Monroe' makes it very desirable (Ray Wood, Castle Howard, North Yorkshire, UK, August 2023). Image John Grimshaw.

'Pacific Fire'

A selection noted for its coral-red stems which are at their best in winter. New growth is vigorous, though plants need full sun to develop best (Dirr & Warren 2019). As for other maples with vivid young shoots such as selections of Acer tegmentosum, Dirr & Warren (2019) advocate cutting back each year to gain the best effect. In summer the foliage is lime green, turning yellow in autumn (Dirr & Warren 2019).

'Pacific Sprite'

A dwarf clone attaining 1.3 m in 10 years (Hatch 2021–2022). Its leaves are somewhat crinkly, darker green than most, and turn orange, yellow or red in autumn (Hatch 2021–2022).

'Si Yama'

A small, densely branched plant speculated to have been derived from a witch’s broom by van Gelderen & van Gelderen (1999). Its leaves are up to 5 cm across, and it is noted as appropriate for bonsai (van Gelderen & van Gelderen 1999).

'Sunglow'

A compact clone attaining around 1 m in ten years, with golden yellow spring foliage, tinted orange or pink if sited in full sun, though dull if grown in shade. In autumn the leaves turn red and purple. Discovered by Fred McMullen of Portland, Oregon and introduced commercially by Buchholz & Buchholz Nursery (Hatch 2021–2022).

'Sunny Sister'

Of somewhat smaller stature than typical for the species, this was selected for its pale-tinted spring foliage, which turns light green in summer (Dirr & Warren 2019). Autumn colour is yellow to orange (Dirr & Warren 2019). Introduced by Talon Buchholz, it is a sister seedling to ‘Sunglow’.

'Victoria'

A cultivar that arose as a chance seedling at the Von Gimborn Arboretum, The Netherlands, and named by former director and acerologist Piet de Jong and introduced commercially by Plantentuin Esveld (van Gelderen & van Gelderen 1999). van Gelderen and van Gelderen (1999) describe it as shrubby, though the photo accompanying the description shows a plant that is distinctly tree-like.