Tree aralia, the only species of the genus, is the plant equivalent of the Amur tiger. It has adapted to the freezing winters of the forest zones of north-eastern Asia although it looks more like a plant of the tropical jungle. To Finnish eyes it resembles the indoor plant fatsi (also called Japanese aralia or castor oil plant, Fatsia japonica), to which it is related. In its native habitat it grows into a massive 30-metre tree, whose trunk can exceed a metre in diameter. The trunk it covered in stout prickles, as are the branches.
The leaves are divided into seven ”fingers”, or lobes, though how deeply lobed they are varies. Those forms in which the lobes are most finger-like are sometimes classed as a separate species or variety (var. maximowiczii). The leaf blade can be up to 25 cms across, the leaf stalk even longer, up to 50 cms. The leaves grow in whorls at the ends of the branches to maximise light absorption. The inflorescences appear in late summer, also at the tips of the branches; they are made up of numerous umbels and can be 25-35cms across, producing berries which ripen to black in late autumn, very tasty to birds.
In the West, tree aralia is a rarity found only in enthusiasts’ collections, with seeds and young plants very rarely available. It is grown in several collections in Finland, where its success seems to vary according to provenance.