Cananga tree has several other English common names, including perfume tree and ylang-ylang. Two perfumery oils can be distilled from this species, depending on the eponymous cultivar group: ylang-ylang oil and cananga oil.
Native to some parts of the Indo-Malayan region, the original range of Cananga odorata is unknown due to spread by humans for ornamental use (particularly the scented flowers). In modern times, the species can be found in tropical and subtropical areas of the world. Since the 1950s, Madagascar and the nearby Comoro Islands have been responsible for ~80% of the global production of ylang-ylang and cananga oils for the perfume industry.
The oils are distilled from glands at the base of the flowers; for every 100kg of flowers, 1-2kg of oil can be extracted, depending on how the flowers are processed and the quality of the flowers. Higher-quality oils (only from the ylang-ylang cultivar group?) are used in perfumes, like Chanel No. 5 (fascinating history of this perfume). Both cultivar groups produce the lower-quality cananga oil (the ylang-ylang oil is distilled off first), and this is then used in scented soap and shampoos. Like yesterday’s methyl salicylate, small concentrations of the oils may sometimes be used in foodstuffs–in this instance, examples include beverages or bakery products.
A comprehensive article is available from the US Forest Service’s Dr. John Parrotta: Cananga odorata (PDF). Additional photographs are available from Australian Tropical Rainforest Plants: Cananga odorata. The World Agroforestry Centre provides a quick summary, including a good botanical description of the tree (PDF).