This is the handsomest of the wingnuts which can be grown successfully in Finland, with large compound leaves of opposite leaflets. Unfortunately the provenance of the seed cultivated in nurseries is hopelessly tender in Suomi winters. Plants from Uppsala have grown to over 20 metres in the Djurbäck Arboretum in Inkoo, southern Finland, in only a few decades. It seems that to thrive, seed must be of suitable provenance and the soil rich and moist, with protection from late spring frosts.
The Caucasian wingnut closely resembles the Japanese. A good way to distinguish between the two is the scales protecting the buds: in the Caucasian they are completely absent; in the Japanese they fall during the winter.