Cassia, also known as cassia lignea or Chinese cinnamon, is said to be one of the oldest of spices. It was known in China as long ago as 27 B.C., in Egypt in the seventeenth century B.C., and it is said to have been familiar to all the people of the Mediterranean area at an early date. These statements are open to doubt and there is probably some confusion with some other bark.

They should, however, be planted close enough to encourage the formation of a tall straight trunk with as few branches as possible. The best spacing is about 1 m between plants. The use of Tephrosia candida (Roxb.) DC. as a nurse crop has been recommended in Sumatra. This may be sown six months ahead of the cassia in rows about 1 m apart and the young cassia trees are planted in clearings about 60-70 cm in diameter made in the Tephrosia, which later can be cut back to 15 cm and spread between the rows.

Intercropping in the first year with groundnuts or other crops is sometimes practised, but care is necessary, as damage to the roots of the cassia can result in infection by canker, Phytophthora cinnamomi.

The bark has been known as a spice from the earliest times, in Western Europe from the seventh century and in England from the tenth, and the tree has been cultivated in the southernmost provinces of China “from time immemorial”. Cassia is described as similar to cinnamon but cheaper and commoner, and synamome was for lordes, but canelle (cassia) was for commyn people. This contemptuous evaluation of cassia is no longer entirely valid.

C. verum (syn. C. zeylanicum) is the only source of cinnamon and cinnamon oil recognized by the British Pharmacopoeia, whereas the United States Pharmacopoeia permits the use of cassia from various sources. For some time the United States’ ban on imports from Communist China precluded the use of Chinese cassia exported direct from China and they obtained their supply of cassia from C. burmannii from Indonesia, C. loureirii from Vietnam and other sources.

In each country, only the forms of cinnamon and cinnamon oil specified in the appropriate national Pharmacopoeia can properly be used for official pharmaceutical preparations, whereas this limitation does not apply for food-flavouring purposes.