Developed, in the course of centuries, from obscure beginnings into an important modern industry, the present-day production of essential oils is based upon principles which vary between two extremes (the first still retaining its original primitive character).
(1) In most instances the aromatic plants grow wild or are cultivated as garden or patch crops by natives of the area concerned. Cultivation of the plants and distillation of the oil represent a family industry often, indeed, only a "side occupation" of members of the family. By primitive methods, and limiting themselves generally to one oil, the natives produce small quantities of an oil, which they sell through field brokers to village buyers, until the lots finally reach exporters in the shipping ports. The price of these oils depends upon the market, which, in turn, is influenced by supply and demand. The natives are usually well aware of prevailing quotations, and prefer stocking up their output to selling it at unattractive prices. This primitive industry is at a very definite advantage because the native operators never value very highly the work done by themselves or their families, while modern methods of production involve specialized and highly priced labor.
This old-fashioned method of essential oil production is characterized by dispersion rather than by concentration. Lack of roads prevents transport of the plant material to centrally located processing plants. The stills, usually small, portable contraptions, low priced and easy to operate, have to be scattered over the regions concerned, thus following the plant material. Such conditions still exist with respect to numerous oils and in many parts of the world, for example in East India (oil of lemongrass, palmarosa, etc.), in China (oil of star anise, cassia), and in Java (oil of cananga), etc.
(2) Advanced processing methods, based upon modern principles of plant breeding, mechanized agriculture, engineering and mass production, represent the competing counterpart of the primitive methods described above. The oils obtained in regular essential oil factories generally possess a quality superior to those produced by natives in backward districts; but the operating expenses are high. In addition to the higher standard of living and consequent higher wages and salaries involved, the amortization of invested capital, taxes and other general overhead expenses increase the costs of production. Under these conditions, a modern factory trying to specialize in the production of only one yearly crop could hardly survive ; operation is profitable only if a variety of plants can be processed and thereby the enterprise kept busy during most of the year. Such an organization would have to produce oils from plants grown mainly in the vicinity, or from dried plants which could be shipped from afar at low cost. In other words, a factory of this type would have to be located near large plantations, connected by good roads, and would require conditions of soil, climate and altitude permitting the growth of varied crops of aromatic plants. Theoretically, this would offer the ideal solution for the essential oil industry, but it involves heavy capital investment and necessitates a great deal of experience and lengthy, systematic agricultural research work before the proper location can be found and the proper crops selected and grown. Highly mechanized farming equipment (bulldozers, tractors, planting, cultivating and harvesting machinery, trucks, etc.) must be employed in order to reduce the high cost of American labor (labor is a much smaller item in the "cost calculation" of the native patch croppers abroad). Furthermore, scientific plant breeding would have to aim at strains with a high oil yield.
9This part of the survey leans on writings by Ernest Guenther, "Essential Oil Production in Latin America," in "Plants and Plant Science in Latin America," p. 205, by Frans Verdoorn, Waltham, Mass., 1945; "Essential Oils and their Production in the Western Hemisphere," New York, 1942, Fritzsche Brothers, Inc.; and "A Fifteen Year Study of Essential Oil Production Throughout the World," New York, 1940, Fritzsche Brothers, Inc.

Only in a few instances has the production of essential oils been placed on a really modern agricultural and technical basis. Previous to World War I, the great essential oil factories in and near New York City, London, Leipzig, and Grasse (Southern France) used to distill essential oils (oils of sandalwood, vetiver, patchouly, etc.) from plant material imported from abroad. The problem of shipping space for bulky raw material which arose during the war forced local growers in various countries abroad to install their own distillation equipment and to process their own plant material for oil. As a result, after World War I, the high cost of transporting raw material prevented manufacturers in Europe and the United States from competing with native producers abroad. Hence the production of essential oils in many instances reverted from a centralized and highly developed system to a primitive and scattered one.
Today only a few essential oils are produced by very modern or "centralized" methods. Among these are the natural flower oils in the Grasse region of Southern France, and the citrus oils of California and Florida. The latter states have succeeded in producing large quantities of high quality oils because they possess a network of good roads and railroads permitting the trucking or hauling of fruit from distant orchards and sections to centrally located, modern processing plants. Because of this feature, the United States has become a large producer and exporter of these oils. In fact, it has achieved independence as regards oils of lemon and orange. In the coming years, a corresponding evolution may take place also in other oils which so far have been distilled in far-off corners of more primitive countries. However, although most essential oils are still imported from regions abroad, where old methods prevail, the American essential oil industry has reached a high standard because of field work carried out abroad and untiring analytical work in the laboratories of private firms and scientific institutions.
The essential oil industry in its present stage is not limited to the production and distribution of essential oils and the improvement of methods, nor to the establishment and maintenance of standards of quality alone, but has come more and more to be concerned with the development, production and testing of synthetic aromatics and mixtures which today find their way into so many products of our advanced civilization. Botany, agriculture, pharmacy and chemistry, engineering, a knowledge of world markets, commercial ingenuity and responsibility have all contributed to the development of the modern industry of essential oils. It is the maintenance of this combination which will keep up the high standard and the general usefulness of this industry.

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