A small amount of a third type, cassia vera, produced mainly in Java, Celebes and other neighbouring islands, is exported mainly from Makassar, the German Federal Republic being the chief importers.

Within each category, there is a further classification according to the thickness of the quills. Ceylon cinnamon quills imported into the United Kingdom are mainly used industrially in the manufacture of a wide variety of processed foods or for the production of cinnamon bark oil or cinnamon oleoresin. A small quantity is either cut up into pieces about 15 cm or ground into a fine powder or mixed with other spices by spice merchants or millers for the retail pharmaceutical and grocery trades.

Kwantung cassia has an oil content of at least 1.7 ml per 100 g, and Kwangsi 3.4 to 4.0 ml per 100 g, according to information provided in 1974 by the Native Product Corporation, Peking (via the British Embassy). This contrasts with Landes (1951), who reported that best quality Kwangsi cassia contained 2 to 2.75 per cent volatile oil and Kwantung 1.0 to 1.2 per cent.

The spices are prepared and supplied to the market in various forms, the most elaborate type of product being the compound cinnamon quills from Sri Lanka.

The National Dahlia Society also works in conjunction with the Royal Horticultural Society towards the better appreciation of the dahlia. The instrument here is the Joint Dahlia Committee, composed of an equal number of members from both societies. This committee is responsible for the classification of the dahlia into its differing forms and sizes, but not for the actual listing of varieties in accordance with this classification which is done by the National Dahlia Society.

Modern varieties, without doubt, are really wonderful, both in formation and in the period and length of blooming. The majority of giant varieties have originated overseas, although we have several raisers of these varieties within the confines of the British Isles, notably that doyen of the dahlia, Mr Harry Stredwick, whose giants are famous the world over.

Certain members of this committee are responsible for the compilation of the National Register of Varieties, a register which is maintained to try to eliminate confusion and duplication of naming wherever possible.

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.

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 type of soil has a pronounced effect on the quality of the bark. In Sri Lanka the best cinnamon grows around Negombo in the Colombo District of the Western Province in fine white quartz sand.

The other main cinnamon area is the Galle and Matara Districts of the Southern Province, where the lateritic gravelly soil of the low country produces more rapid growth, but the bark obtained is somewhat thicker and coarser than that of the Negombo District. Rocky and stony ground is unsuitable. Waterlogged and marshy areas should be avoided, as they give an undesirable bitter product which is much less aromatic.

Several cultivars with distinctive local names exist in Sri Lanka. The forms recognized by growers include sweet or honey cinnamon, snake cinnamon, camphor cinnamon, astringent cinnamon, mucilaginous cinnamon, wild cinnamon and bloom cinnamon. Their characteristics are not given, but of these only sweet or honey cinnamon is cultivated extensively.

It is the dominant species of the secondary vegetation of the higher and middle slopes. It also occurs and is sometimes planted in the coconut plantations and is also found in the calcareous coastal flats. Mahe is by far the largest producer, as the very steep rocky terrain of Silhouette makes exploitation difficult.

Cinnamon bark oil is a pale-yellow liquid possessing the delicate aroma of the spice and a sweet and pungent taste. Its major constituent is cinnamaldehyde, but other components present in minor or trace quantities impart the characteristic odour and flavour which distinguishes this oil from other Cinnamomum bark oils. These components include eugenol, eugenol acetate and small amounts of aldehydes, ketones, alcohols, esters and terpenes. Arctander (1960) attributes the powerful characteristic notes of good oils to the presence of methyl-namylketone together with other, aldehydes and ketones. However, detailed studies of the relationship of the oil composition to its organoleptic properties have not been reported in the literature.

The variation in the properties of the spice according to its grading have been described in the `Products and end-uses’ section, and the current standards are given in the ‘Standard specifications’ section.

Cinnamaldehyde was identified as the major constituent of Sri Lankan cinnamon bark oil by Dumas and Peligot (1834, 1835), and more detailed analyses of the oil composition were undertaken later by chemists of the Schimmel Co. (1892c) and by Walbaum and Huthig (1902).

Camphor oil is obtained by distilling the wood or leaves of Cinnamomum camphora (L.) Presl, which is a native of China, Japan and Taiwan, the last island producing the greatest amount. C. camphora can be distinguished from the other species of Cinnamomum mentioned above by the leaves being pinninerved, whereas the others have three to five distinct nerves from the base of the leaves proceeding towards the tip; camphor also has stout dormant buds. A large proportion of the world’s camphor is now produced synthetically from pinenc, a turpentine derivative, or from coal tar. Camphor is used in the manufacture of celluloid, in disinfectants and chemical preparations, and has a wide range of medicinal uses. Safrole, produced from the residual oil after camphor extraction, is used in soap and perfume manufacture.

Other species of Cinnamotnum, whose barks are used as spices or in medicine include: C. culilawan (Roxb.) Presl from the Moluccas; C. iners Reinw., which occurs from western India and Tenasserim (Burma) to Malaysia, Indonesia and the Philippines; C. javanicum Bl. in Malaysia and Indonesia; C. part henoxylon (Jack) Nees in Tenasserim and western Malesia; and C. sintoc Bl. in Java. All the binomials and authorities in this section are taken from Kostermans.

Long stemmed blooms of Dahlia can be supported with pad of soft material used to support weak necked blooms-not required for stronger stemmed varieties. Stem and cane should be tied at not less than two places above and two below the first pair of leaves, ignoring the single leaves which occasionally appear.

If a light, thin cane is secured to the stem, extending from just below the bloom to a point about 1 foot below the first pair of leaves, the danger of breakage is negligible. Make one tie just below the bloom, and at least one below the first joint.

This tip is particularly useful with varieties with rather soft footstalks as these often bend beneath the weight of the developing bloom, although the stem usually stiffens once the bloom reaches maturity. In this case it is best to cut with the cane still tied to the stern, and to leave the cane in position until the bloom has been vased up and has had opportunity to become fully charged with water.

The nutmeg tree, Myristica fragrans, is unique among the spice plants as it produces two separate and distinct products – the nutmeg which is the kernel of the seed and the mace which is the dried aril that surrounds the single seed within the fruit. It is a spreading evergreen tree, usually dioecious, which is native to the Moluccas in the East Indian Archipelago, belonging to the small primitive family Myristicaceae. Nutmegs reached Europe after cloves.

By 1650 the order had become fairly effective. Most writers comment that the scheme was thwarted by fruit pigeons which swallowed the seeds and voided them on neighbouring islands. The original source of this statement, which has been faithfully copied, is hard to identify, but the story, like the seeds, is rather hard to swallow. It is possible that the spice occurred in regions of the islands unknown to the Dutch, and there was a brisk trade in spices by the natives with Mindanao and Kedah.

Although perhaps not entirely a matter proper to a treatise on dahlias, the period of a dahlia’s life in which it inhabits a greenhouse or frame plays such an, important part that it seems advisable to digress a little.

It may sound strange that so much stress is placed on keeping temperatures down, but whereas it is not difficult to maintain a reasonable temperature even on a cold clay by a variety of means, it is most difficult to prevent the temperature soaring on a sunny clay in a small house. Cuttings soon flag if exposed to excessive dry heat, and, once having flagged, are not only slow in recovering, but arc also more likely to damp off and much more likely to take a long while to strike. So the maxim is-shade!

Usually a water circulating heating system will give too much heat for a small house, while most alternative systems are either expensive or somewhat unsatisfactory in one way or another.