Harvesting does not usually take place until the trees are at least 10 or 12 years old, unless economic necessity compels the cultivator to harvest them at 4 or 5 years, when the bark will be of inferior quality. They may even be left until they are 20 to 30 years of age, while forest trees may be 40 or 50 years old when they are discovered.

The bark is removed from the standing tree at the time when it lifts easily, starting with the main branches and working down the trunk. A bambdo scaffolding may be erected for the purpose. Horizontal cuts are made about 40 cm apart and vertical cuts some 25-35 cm apart. The rectangles of bark are then removed with the aid of a horn or bamboo spatula. Finally, the tree is felled and the inferior bark removed from the smaller branches. A stump may he left to encourage coppicing.

In comparison to cinnamon bark oil, the production of cassia bark oils is on a relatively small scale with distillation being undertaken in the importing countries. These oils find a limited use in soaps, perfumes, some spice essences and beverages.

The four Cinnamomum species of importance in international trade are C. verum (cinnamon) and the cassias from C. cassia, C. burmannii and C. loureirii. The dried barks of all four species are widely used as flavouring agents; and, in addition, they are utilized to a varying extent for the distillation of their bark oils and for the preparation of solvent- extracted oleoresins.

Cassia oil of commerce is produced in China. It contains cinnamaldehyde as its major constituent and is used for similar purposes to cinnamon bark oil in perfumery and flavouring (after rectification) but its applications are rather more limited.

The cinnamon and cassia barks of commerce have been traditionally marketed under a number of vernacular names. The grading of Ceylon cinnamon is quite elaborate in comparison to other sources of the spice, and exports include compound quills and certain lower grades, obtained as by-products in the preparation of quills, which are known as 4quillings’, `featheritigs’ and ‘chips’. Grading is essentially done on the basis of physical appearance and there is no close correlation with the volatile-oil content, which may range between 0.5 and 2.0 per cent.