by FAO STAFF
THE Conference of the Food and Agriculture Organization held at Rome in 1951 requested the Director-General to endeavour to organize a Eucalyptus Study Tour in Australia, financed in part from the funds of the Expanded Technical Assistance Programme.
After an agreement had been successfully negotiated with the Government of the Commonwealth of Australia, invitations were issued to Member Nations likely to be interested. Each country was invited to send not more than two participants, who should be senior officers of forest services or commercial enterprises, having a working knowledge of the English language. The Commonwealth Government assumed responsibility for all technical documentation, lecturing staff, travel and accommodation arrangements, while the co-operation of the six State Governments and of numerous commercial firms was essential to the organization of the tour. For all this assistance and hospitality the participants passed a vote of thanks at the end of the tour.
The response of Member Governments to this invitation was evidence of the wide interest taken in this project and resulted in a much larger party than was anticipated. Thirty-four participants from 24 countries1 assembled in Canberra, Australian Capital Territory, on 1 September 1952 and the tour formally concluded in Sydney on 28 October.
1 The countries represented were: Argentina, Belgium, Belgian Congo, Brazil, Burma, Cambodia, Chile, France, Indonesia, Israel, Italy, Jordan, Kenya, Laos, Libya, Malaya, Netherlands, New Guinea, New Zealand, Nigeria. Spain. Thailand, Turkey, U.S.A., Venezuela.
Figure 1 - Regrowth of Eucalyptus maculata on Bodalla State Forest, New South Wales. The area cleared was filled with trees from seed.
The main purpose of the tour was to familiarize participants with the great wealth of eucalypt species in Australia and their adaptability to diverse climatic and soil conditions.
The detailed objectives may be summarized briefly as follows:
1. to study the natural occurrence of Eucalyptus species in Australia;
2. to obtain particulars of the silviculture of these species, their formations, associations, natural and artificial regeneration;
3. to study growth rates and methods of forest management:
4. to investigate the climatic and edaphic factors controlling the occurrence of eucalypt species;
5. to study the utilization of eucalypt timber for sawn timber, poles, piles, girders, plywood, pulp, hardboard, mining timbers and also of minor forest products such as tannins and oils;
6. to examine methods of logging, milling, seasoning and preservation;
7. to study certain other associated genera and where possible, coniferous plantations.
It was considered that the opportunity afforded by this tour should enable countries formulating afforestation programmes to determine on a more scientific basis the potential usefulness of Australian species for their particular requirements.
It must be stressed that it was never intended that this two-months' tour should constitute an intensive or exhaustive survey, but that the period would, of necessity, be occupied by a general appreciation of the genus as a whole and would enable experienced participants to use this background for the selection of species and the evaluation of technical literature.
The Forestry and Timber Bureau of the Department of the Interior was designated by the Government of Australia as the organization responsible for the conduct of the tour.
The tour was officially opened by the Rt. Hon. R.G. Casey, Minister for External Affairs. and commenced with an Orientation Week at the Australian Forestry School, Canberra, covering introductory lectures and field work.
The programme included visits to all States, excluding the Northern Territory, and covered all major forest types With the exception of the North Queensland rain forests. An insight into the activities of the forest products research laboratories of the Commonwealth Scientific and Industrial Research Organization was provided by a three-clay visit. In addition pulp and paper mills, hardboard factories. wood distillation and tannin extract plants, sawmills, sleeper mills. and a handle factory were inspected.
The tour covered approximately 5.000 miles (8,000 km.) of air travel and a similar distance by road.
Figure 2 - A thirty-five to forty years' old stand of Eucalyptus grandis on Manning River National Forest, New South Wales.
The twenty-four countries represented in the Group extended over an extremely wide range of environments, and each country had in view one or more definite objectives which might be achieved by planting Eucalyptus species. The extensive travel necessary to cover as complete a range of Eucalyptus species as possible and the limited period available did not permit close study. The following observations are therefore general rather than specific.
Biology and ecology
The Group was impressed with the work being clone to facilitate identification of Eucalyptus species, varieties and hybrids. The need for effective aids to identification is even more urgent overseas, where geographic occurrence, a powerful aid in Australia, is of no assistance.
Examination of the forests enabled individuals to widen their knowledge, hitherto derived mostly from the literature on the subject of the Eucalyptus formations, viz: mallee, savannah, woodland, dry and wet sclerophyll forest and rain forest.
A most important feature is that some species are found exclusively in one of these formations while others are found in more than one. There are some plastic species, each of which may constitute a cline or comprise a number of disconnected races. Inadequate as present knowledge of racial variation within the most important Eucalyptus species may be, the existence of such variation must be taken into account in seed collection and species introduction programmes.
The chief benefit derived from the tour concerns the choice of species. Direct observations of species in their own environments should greatly facilitate the choice of those with desired silvicultural and technical properties or capable of forming protective cover. For example, mallee species, though of slow growth and poor form, may be valuable in arid countries for soil stabilization windbreaks or the production of poles. fuel, essential oils or tannins. The high altitude species. particularly those of the ash group, appear to merit trial in temperate climates. The choice of species for regions where temperature and precipitation are less significant factors has been widened by local observations and from the information supplied during the tour.
A problem which attracted the attention of the participants was the influence of Eucalyptus stands on the soil. Except in the wettest type of forest there is very little accumulation of litter and humus and it appears desirable to determine whether or not the artificial establishment of an undergrowth may be beneficial. Some Australian Acacia species might be tried for this purpose.
Data on the growth of Eucalyptus species both in Australia and elsewhere are inadequate and not always comparable. There is, however, evidence that growth of a number of species is more rapid in some overseas countries. It was suggested that in addition to differences of environment the absence of natural enemies, particularly insects. is a contributing factor.
The three systems of working Eucalyptus forests that were seen were a single tree selection system, a group selection system and a system of clear felling leaving scattered seed trees. The tree selection system appears to be the least suitable except for tolerant species or for dry sites.
Natural regeneration of Eucalyptus is very easily obtained after clear felling, opening of the canopy, or after fire, either by seed or coppice. The reduction of the undergrowth by fire or exploitation may make an important contribution to the successful establishment of such regeneration.
Fire is a grave problem in Australia. It is used in grazing practice and in clearing for land settlement but is a serious hazard to standing timber. Used with great caution it can be beneficial in securing regeneration in Australia and possibly in other countries. While most Eucalyptus species have the power to recover after fire, some have not. It is probable that in many countries outside Australia this important consideration and the significance of ligno-tubers in securing regeneration are not fully appreciated.
From the great density of the crops of regeneration, mostly even aged, it is reasonable to suppose that thinning is necessary to secure optimum growth. More thinning studies are required.
It has been observed that in the ecotone between rain and Eucalyptus formations, the rain forest species invade Eucalyptus forest, and form in many cases, a dense understorey interfering with good eucalypt regeneration.
The establishment of Eucalyptus plantations using tubed or potted stock presents little difficulty in Australia. Successful plantations resulting from direct sowing, for example E. astringens, were seen. These methods have possibilities in other countries.
The plantations of Araucaria cunninghamii in Queensland and of Pinus radiata in South Australia were impressive. Softwood plantations are likely to fill as important a role in Australia's timber economy as Eucalyptus species do in many other countries.
The striking results of application of phosphates and zinc salts in securing healthy growth of Pinus species on certain soils in Australia are of world wide interest and merit careful study in other countries.
Little information on the incidence of damage to Eucalyptus species by insects and other pests was available to the Group. It is desirable to draw attention to the necessity for guarding against the introduction of Australian pests of Eucalyptus into other countries.
The Group was impressed with the measures now being taken to guard against repetitions of the very serious forest fires which have taken place.
Utilization practices seen during the tour varied from the most primitive and wasteful to the most highly organized and efficient. The adoption in any country of any practice seen must depend in general on the particular combination of present and potential Eucalyptus resources, other timber resources and the degree of industrial and economic development of that country.
Although the small scattered units of Australia's forest industries are mainly of low individual productivity, their prevalence has the off-setting advantage of permitting a surprisingly high level of silviculture and forest productivity for such a relatively undeveloped country. This point may be worth careful consideration elsewhere.
Perhaps the most instructive feature of the tour from the utilization point of view was the visit to the Melbourne laboratory of the Division of Forest Products of the Commonwealth Scientific and Industrial Research Organization. The Group was most impressed by the happy balance between basic and applied research achieved and found that the talks and demonstrations presented by the staff served to bring the whole tour into perspective. The following impressions are grouped by class of product.
Lumber (sawn timber)
The studies of seasoning and the phenomenon of collapse in drying conducted by C.S.I.R.O. and the reconditioning treatment developed to reconstitute collapsed timber are of broad significance. The generally, good qualities resulting from the application of this treatment in the ash group of eucalypts have been realized in Australia only in recent years and are not yet sufficiently appreciated in other countries where these species may be grown.
The close utilization of small dimension conifer thinnings to produce flooring and case lumber was especially interesting.
Fuelwood, charcoal and distillates
Production of charcoal and wood distillates, as seen at Wundowie, Western Australia, is of interest to countries suffering from fuel short ages. The possibility of using mallees for firewood production or for the distillation of Eucalyptus oils from the leaves may have application in semi-arid countries.
Posts and poles
Observations made during the tour should enable the selection of species to produce more durable transmission poles than those used at present. It was, however, noted that there was a tendency towards preservation of Eucalyptus in the round, and the technique of treatment of power poles is significant in this respect.
Eucalyptus astringens, the bark of which contains up to 40 percent of tannins and which, with an annual precipitation of 20 inches (500 mm.) or less, produces crops of bark on a short rotation as well as a timber of great toughness, is of potential value in areas with slight rainfall.
In view of the housing needs in most countries, much interest was taken in the production of hardboard. The Asplund process plant seen at Burnie, Tasmania, is notable for its utilization of wood waste, and the Masonite plant at Raymond Terrace, New South Wales, for the complete utilization of mixed forests of low quality.
The three paper mills seen, using respectively mechanical, soda and kraft processes, showed the possibilities of making high quality paper of many types from pulps produced wholly or partly from the relatively short fibered Eucalyptus wood. The market for smell conifer thinnings provided by this industry is of general interest.
Before the participants dispersed, a short report was drawn up summarizing in general terms what had been seen. A number of suggestions were made to FAO and to the Australian Forestry and Timber Bureau on possible follow-up action.