Toona is a genus of deciduous to semi-evergreen trees in the mahogany family, Meliaceae, placed in the order Sapindales. Commonly known as red cedar or toon (also spelled tun), the genus comprises around six accepted species distributed from Afghanistan and Pakistan south through the Indian subcontinent, east across China and the Korean peninsula, through Southeast Asia and Malesia, to Papua New Guinea and eastern Australia.
Trees in this genus are typically large timber trees with pinnate leaves and small, fragrant flowers borne in terminal or axillary panicles. The genus occupies a similar ecological niche to the related New World genus Cedrela, with which Toona was formerly combined in some classifications; modern taxonomy restricts Cedrela to the Americas while Toona covers all Old World members of that lineage.
The best-known species is Toona sinensis, the Chinese toon or Chinese mahogany, which is both a valued timber tree and an important food plant in China, where young shoots and leaves are harvested as a spring vegetable and used in traditional medicine. Toona ciliata, the Australian red cedar, was one of the most heavily logged timber species in eastern Australia during the 19th century. Other species such as Toona sureni and Toona calantas are important timber trees across Southeast Asia and island Melanesia respectively.
Etymology
The genus name Toona is a Latinised form of the vernacular name "toon" or "tun" used in India and Nepal for these trees. The same name also gives rise to the genus's common English designation, toon or toona.
Distribution
Toona is native to a broad arc of Asia and the western Pacific, from Afghanistan and Pakistan south to India and east through China and the Korean Peninsula to Japan, continuing south through Southeast Asia, Malesia, Papua New Guinea, and eastern Australia. Individual species have more restricted ranges: Toona ciliata spans Pakistan to Australia; Toona sinensis ranges from Pakistan to China and Malesia; Toona sureni occurs in southern China through Malesia and Papuasia; Toona calantas is centred on Malesia, New Guinea, and the Bismarck Archipelago; and Toona fargesii is confined to the eastern Himalayas and southern China.
Taxonomy Notes
Toona was historically treated as part of a broadly circumscribed Cedrela, a genus that spans both Old and New World mahogany relatives. Modern taxonomy separates the two: Cedrela is now restricted to American species, while Toona encompasses all Old World members of that lineage. The genus belongs to tribe Cedreleae within the family Meliaceae (order Sapindales). Plants of the World Online recognised six species as of April 2024.
Cultural Uses
The young shoots and leaves of Toona sinensis (Chinese toon) are a traditional spring vegetable in China, eaten stir-fried, pickled, or as a flavouring sauce. The species also features in Chinese traditional medicine. Several Toona species — particularly Toona ciliata in Australia and Toona calantas in the Philippines — have been heavily exploited for their timber, which is prized for furniture, cabinetry, and boat-building.
