A low, deciduous tree, often scarcely more than a shrub, but sometimes over 30 ft high; branchlets glabrous. Leaves seven- or nine-lobed, almost circular in general outline, but heart-shaped at the base, 3 to 5 in. wide, the lobes unequally or doubly toothed; lower surface hairy when young, but ultimately almost glabrous; stalks stout, 1 to 11⁄2 in. long. Flowers in small corymbose clusters, each flower 1⁄2 in. across, the sepals reddish purple; petals smaller, dull white. Fruit with wings about 11⁄2 in. long, 3⁄8 in. wide, spreading almost horizontally, red when young.
Native of western N. America from British Columbia south to California; introduced by Douglas in 1826. This maple is very distinct, and one of the most ornamental in its flowers. In April, when well in bloom, the wine-coloured sepals contrasting with the whitish petals make a very pretty display, especially as they are associated with conspicuous crimson bud-scales. Its leaves frequently die off in beautiful red and orange-coloured shades. If it is desirable that it should form a trunk, the lower branches should be pruned off as the tree grows in height until sufficient clean stem has been formed. But, allowed to grow in its natural way, it makes a low, wide-spreading bush of pleasing form, often with the lower branches laid on the ground and taking root there. Owing to this peculiarity it forms impenetrable thickets in a wild state. It is an admirable subject for a lawn in a small garden.
From the Supplement (Vol. V)
† cv. 'Monroe'. – Leaves deeply dissected, the sinuses between the lobes reaching almost to the centre of the leaf, and the lobes themselves deeply incised. It was found by Dr Monroe growing wild in the Cascade Mountains of Oregon and propagated (Brian Mulligan in Baileya, Vol. 19, pp. 111-15 (1974) and see also J.D. Vertrees in Int. Dendr. Soc. Year Book 1978, pp. 82-3). For other variants of A. circinatum, see the second of these two articles.