History of oil production1
The early days
Eucalyptus oil was distilled as early as 1788, the first year of white settlement in Australia, when Governor Phillip sent a sample to Sir Joseph Banks, and in 1790, John White, the Surgeon-General, despatched a quart of oil of Eucalyptus piperita to England. However, it was not until 1852 that a still was set up for the commercial distillation of eucalyptus oil. Joseph Bosisto, who had emigrated from England four years earlier, established his still on Dandenong Creek, about 40 km southeast of Melbourne, with the encouragement of Ferdinand von Mueller, then Government Botanist in Victoria.
In those early days, before much was known about the chemical composition of eucalyptus oils, several different species were worked, giving oils of varying composition. Stills for the production of oil were established in Gippsland, just east of Melbourne, and in Tasmania. The oil was used as a disinfectant, as a solvent, and for its therapeutic value. For the distiller of the oil, the critical factor was the yield of oil rather than its composition and, initially, species containing a high percentage of oil were favoured.
The search for high-yielding species saw the commercial activity move to western Victoria, particularly in the southern Mallee region, and then east towards central Victoria. At the same time stills were established in Tasmania and South Australia, particularly on Kangaroo Island.
Early research
While the commercial distillers were seeking better sources of the oil, scientific investigation began to make significant headway only during the last two decades of the nineteenth century.
For the industry to develop it was essential to know the chemical composition of the different oils, whether the composition was constant within a species, and the factors, if any, which affected the yield and composition. At this time, most oil production was in Victoria, but the main research was carried out at the Technological Museum in Sydney. This institution, later named the Museum of Applied Arts & Sciences, was set up in 1880 to, inter alia, ‘investigate the economics of the natural products of Australia, and of New South Wales in particular, and to make this information available to the public’ (Grolier Society 1965). Although it covered a wide field, a lot of its research was on the essential oils of the many plants unique to Australia.
1 A more detailed history of the industry is given by Shiel (1985).
Its reputation grew and the Museum soon became the foremost authority on Australian essential oils, particularly the eucalyptus oils.
During the Museum’s ninety-nine year life, the combination of a botanist and a chemist as the research leaders was of great value to the essential oil industry. The initial work of the eminent botanist J.H. Maiden was followed, in turn, by that of R.T. Baker and H.G. Smith, A.R. Penfold and F.R. Morrison, and J.L. Willis and H.H.G. McKern, who, with their more recent successors R.O. Hellyer, E.V. Lassak and I.A. Southwell, have provided the scientific basis necessary to develop the industry. The early work established the chemical composition of the oils, within the limits of chemical knowledge and methods then available. Penfold, together with his co-workers, was particularly prolific throughout the 1920s, 1930s and 1940s (Coppen and Dyer 1993). The composition of the oil from a given species appeared, then, to be relatively constant.
While the oil yield was also characteristic of the species, it could vary markedly between individual trees within a natural population.
However, further research showed that within some species pronounced chemical variation could exist. The plants which exhibit such variation, first termed ‘physiological forms’ by their discoverers, Penfold and Morrison, are now usually referred to as chemical variants, chemotypes or chemovars. Marked variation in oil composition may exist between populations or between individual trees within a population. An early example of this phenomenon within Eucalyptus was found to be that of E. dives. Some populations (‘Type’) produce oil commercially valued for its 40–50 per cent piperitone content; other populations (‘Variety C’) produce oil rich in cineole, also commercially valuable. Yet other variant populations, of no present commercial importance, are known: ‘Variety A’ yields an oil consisting chiefly of hydrocarbons, whilst ‘Variety B’ yields oils of variable composition, made up of constituents found in the other three forms.2However, for practical commercial purposes, populations of trees yielding oils of the desired composition have now been well defined and the oils distilled from them vary in their properties only within narrow limits. Recent work indicates that genetically determined quantitative variation (often to an extreme degree), rather than qualitative variation, accounts for these chemical forms.
Oil-producing species
Of the hundreds of species of eucalyptus, most produce an oil, but few have oil of commercial value. To be of such value, the quantity of oil in the leaves must be at least 1 per cent of the fresh weight of leaf and the chemical composition must be of interest to the market. Apart from one or two speciality oils, such as those from E. olida (see below) and E. staigeriana (produced in Brazil), there are only three types which presently meet these criteria: oils rich in cineole, piperi-tone and citronellal. In Australia, the citronellal type has only been produced to a very small extent.
In the early stages of the industry, the species worked near Melbourne were those which produced the cineole-type oil, although the cineole content varied anywhere between 30 and 70 per cent. ‘Phellandrene’ (mainly -phellandrene) was a common constituent. It is not easy to be sure which species were worked because at that time the taxonomy of the genus was not well established. By the fourth quarter of the nineteenth century E. globulus oil, containing 60–70 per cent cineole, was being produced in southern Victoria and Tasmania. Following the first inclusion of
2 The terms ‘Type’, ‘Variety A’, ‘Variety B’, etc., were introduced in the 1920s and applied chronologically within a species as each distinct type of oil was enumerated. It is preferable, nowadays, to avoid using these terms and to state the particular chemical variant by name.
eucalyptus oil in the British Pharmacopoeia (BP) in 1885, compliance with the specification required increasingly higher levels of cineole, and by 1924 the minimum cineole content was 70 per cent, the level at which it is today. This made E. globulus more popular since the cineole content could be increased to 70 per cent or more by simple rectification and the phellandrene content was negligible. The BP allowed only a very low level of phellandrene. It still does, although there appears to be no good reason for this.
Towards the end of the nineteenth century the main part of the industry was in the central western part of Victoria, where availability of good-yielding, high-cineole, phellandrene-free oil attracted distillers. Although oil was extracted from several species, including E. viridis and E. sideroxylon, and elsewhere from E. radiata and E. robertsonii and others, the industry in the cen-tral and western part of Victoria was firmly based on E. polybractea. Oil was also produced from the same, hardy species in the mallee country of the western plains of New South Wales. The oil is high in cineole, 78–88 per cent, and phellandrene-free; it is also produced in reasonable yields.
E. polybractea has a remarkable ability to coppice after harvest and grows on land which is of lit-tle use for anything else. In other parts of New South Wales, and parts of Victoria, cineole vari-ants of E. radiata and E. dives were the major source of the medicinal type of eucalyptus oil, particularly the 70 per cent cineole grade which conformed to the several national pharma-copoeias which listed eucalyptus oil.
In the early part of the twentieth century, oils from various types of E. radiata and E. dives were produced on the south coast of New South Wales and on the mountains further west. In addition to pharmaceutical applications, much of the production, particularly that from E. dives and the phellandrene variant of E. radiata (then known as E. phellandra), was used for mineral flotation and in disinfectants.
Commercial production
Although hundreds of distillers have been in business during the 140-odd years that eucalyptus oil has been produced in Australia, there have been just a few major ones in the industry. Joseph Bosisto, the initial force in the eucalyptus oil industry, continued to be involved in it until his death in 1898. The following year, J. Bosisto & Company Pty Ltd was constituted, and operated until 1951 when it became a subsidiary of Drug Houses of Australia (DHA). DHA was taken over by Slater Walker in 1968. In 1974, Peter Abbott purchased the eucalyptus oil section of DHA and the name Felton Grimwade & Bickford, the present name of the company. This company also owns the name Bosisto & Co., which is still in use today, and the Bosisto Parrot Brand name.
Early on, F.H. Faulding & Co. became involved in eucalyptus oil production, particularly in Victoria and South Australia and, to some extent, New South Wales. This company has main-tained its connection until the present day. In 1880, the Tasmanian Eucalyptus Oil Company started in Tasmania. It moved its operations to Melbourne in about 1920 and remained a major buyer until 1947. W.K. Burnside Pty Ltd were one of the main buyers and leaseholders of land for oil production from the 1920s to the 1960s. This company also operated in New South Wales.
In 1912, Fred Webb of Braidwood, a gold fossicker, distilled oil from the narrow-leaved pep-permint, E. radiata (phellandrene variant). He went to Sydney and while there ordered a suit from Mr A.J. Bedwell, a tailor who carried out a lot of country order business. The suit, when made, was sent to Braidwood and to Mr Bedwell’s consternation payment was made by the arrival of a small drum of eucalyptus oil. Bedwell not only succeeded in selling the drum of oil but soon sought more. By 1919 he gave up his tailoring business and became the major force in eucalyptus oil in New South Wales until selling out to Plaimar Ltd of Perth in 1950.
A.J. Bedwell Pty Ltd continued producing as a Plaimar subsidiary until 1971, when its euca-lyptus oil interests were acquired by G.R. Davis Pty Ltd.
The eucalyptus oil industry continued to be centred in Victoria until about 1950, producing mainly cineole-type oils. It had provided work for many men and a lot of oil was produced, but the industry was not stable and was profitable for the producers for short periods only. For most of the time it was subsistence farming. The main problems faced by the industry were fluctuat-ing markets, due mainly to competition from other countries, replacement of the oil with alter-native, cheaper products – particularly in the case of mineral flotation – and, in recent years, the stubborn refusal of all Victorian state governments to allow adequate tenure of land.
In the early post-war years there was a world shortage of menthol. Plaimar Ltd had succeeded in earlier years in producing l-menthol from l-piperitone, the major compound of E. dives (Type) oil. Several other manufacturers in Australia, Europe and USA were able to produce liquid menthol from this source and the demand for piperitone-rich E. dives oil increased substantially.
The main stands of E. dives (Type) are in southern New South Wales and, as a result, much of the industry moved there. The production of cineole-rich oils also increased in New South Wales, while continuing in Victoria. The demand for locally produced E. dives (Type) oil lasted, with fluctuations, for about twenty years, until other countries, particularly South Africa, were able to produce low-cost oil. More importantly, production of menthol from alternative sources (natural menthol from Mentha arvensis and synthetic menthol from turpentine) could supply the world’s needs and the piperitone route from E. dives became increasingly less economic.
Early methods of production
For the first hundred years of the industry, almost all eucalyptus oil was produced in very simple bush stills by steam distillation at atmospheric pressure. The typical bush still consisted of a simple tank, usually mild steel, into which leaf and terminal branchlets were stacked on a grid about 15–30 cm from the bottom. Water below the grid was heated by a fire directly below the tank. The steam so generated passed up through the leaf to an outlet just below, or sometimes through, the lid. The resulting mixture of hot oil and water vapours was led to a condenser – often simply a long pipe passing through a dam or stream – and the condensate then passed to a separator where the top layer of oil was removed from the oil–water mixture. In some cases steam was produced in a separate boiler and injected into the tank holding the leaf. This was necessarily so when wooden vats, rather than steel tanks, were used to hold the leaf. These simple stills were used because they were easy to construct and operate, were low-cost (second-hand tanks were often used), and could easily be set up and dismantled, an advantage when they were used in areas where there was insufficient leaf available to support a large or permanent operation. There were, of course, some much larger and more sophisticated plants operating in the early stages of the industry, where large natural stands of the required species were available.
These plants were usually, but not always, established and owned by one of the major companies referred to earlier. It is worth noting that the oil produced in the simplest direct-fired still is not inferior in quality to that produced in the most sophisticated apparatus.
It is fortunate that in stands of commercial oil-bearing species the required trees usually dominate the stand. Furthermore, where a single species is worked, the composition of the oil is similar throughout the stand, although the yield of oil might differ substantially from tree to tree. There are some exceptions to this but, generally, once a stand of trees with good quality oil is found, the producer can harvest it with confidence.
All the commercial oil-bearing eucalypts coppice well and, providing the interval between harvests is not too short so that there is no decline of vigour in the production of foliage, they
can be worked on a sustained yield basis. Coppicing was practised from the early days of oil production. The only tools required were an axe for felling the tree and a heavy knife for remov-ing the leaves and terminal branchlets. In the case of the mallee species, that is, the multi-stemmed trees commonly found in the drier inland areas, the tree is normally cut at, or close, to the ground using a billhook or curved knife. Regrowth comes from the lignotuber just below the ground. In the early years of the industry this arduous work was done mostly by itinerant workers, often as an alternative to prospecting for gold. Few were able to make a good living because of the low value of the oil. Nevertheless, production of oil gave a start to many of the post-war migrants. When farms were being developed on land where oil-bearing trees occurred, production of eucalyptus oil provided a cash return before the traditional agricultural crops matured. New farmers were prepared to sell oil cheaply just to get a cash income.
Competition with other producers
Ever since the industry first started in Australia other countries have planted commercial oil-bearing eucalypts and for almost a century have been able to offer oil on the world market.
The main early competitors were Spain and Portugal, where oil was produced, mainly from E. globulus, as a by-product of the timber industry. In Australia, despite the advantage of low costs for much of its history, high production costs in the 1950s, and for some time after, made it uncompetitive in many world markets, including the eucalyptus oil market. The advantages of producing oil as a by-product, rather than the sole product, proximity to the main markets, and a low wage structure, enabled first the Iberian countries, and then China, to put oil on the market at prices which Australia could not meet. South Africa, too, began to supply Australia with piperitone-rich oil from E. dives (as was noted earlier) and medicinal (cineole-rich) oil from E. smithii. It became apparent by the 1960s that if the industry were to survive, mechanisation of production and development of superior trees in plantations was essential.
It is unfortunate that Australia has been unable to retain the larger part of this uniquely Australian product. However, very rapid growth of Eucalyptus in other countries, probably due to the absence of natural predators, together with the factors noted above, meant that not enough money could be generated in the industry, either to make it profitable for producers or to provide the capital needed to develop the industry. The value of the product on the world market, except for quite brief periods, has not been enough to cover production costs in this country. Much of the land cleared of oil-bearing trees for planting traditional agricultural crops is actually better suited to growing trees for oil. Except for very small areas this calls for plantation development, which is costly and beyond the financial capacity of most producers. Furthermore, as noted earlier, in Victoria, where larger producers could have financed such development, short-sighted Government policy has frustrated such moves by its refusal to recognise the need for reasonable term land tenure.
Modern methods of harvesting and production
On the plain country, attempts were made as early as 1950 to mechanise harvesting and, although not the complete solution, they did demonstrate that cutting the tree using powered tools was possible without detriment to its health.
The problem of mechanising harvesting of natural stands is that the land is usually uneven and contains rocks, stumps, logs and holes. There are also, initially, other plants which, if harvested, might contain products which would be co-distilled with the eucalyptus oil. Clearing the site of unwanted obstacles is therefore the first task, and in many areas this is a large and
costly job. Once it is possible to operate normal agricultural machinery on the land to be harvested the aim is to reduce the manual work to a minimum. The traditional technique of cutting the coppice with a knife, laying the cut material in heaps, loading the heaps on to a vehicle, transporting the leaf to the still and loading the still, has all to be done, if possible, mechanically.
The idea of bringing the still to the area to be harvested was thus conceived and, after many trials, a machine was developed which was strong enough to cut the mallee coppice at ground level and elevate the material into the mobile still towed behind. Partial mechanisation was achieved by several distillers in the late 1960s, but the first effective, fully mechanical,
The idea of bringing the still to the area to be harvested was thus conceived and, after many trials, a machine was developed which was strong enough to cut the mallee coppice at ground level and elevate the material into the mobile still towed behind. Partial mechanisation was achieved by several distillers in the late 1960s, but the first effective, fully mechanical,