Silvicultural Research Conference Bulolo 26 to 30 August 1968

There were discrete areas of high and low density.28 The correlations of weighted whole tree density with weighted disk density at ground level and weighted disk density at breast height were not significant. However the weighted disk value for density at 10% height was significantly correlated to weighted whole tree density at the 1% level of probability, indicating that would be the height at which sampling for whole tree wood density would need to take place. Sampling at 10% height was feasible.

Silvicultural Research Conference Bulolo 26 to 30 August 1968.

On Saturday 24 August I flew from Rabaul to Lae, stayed there overnight, then flew to Bulolo on Sunday 25 August. The Silvicultural Research Conference was held at the Forestry School in Bulolo from Monday 26 August to Friday 30 August 1968 inclusive. Most of the senior officers of the Department were in attendance. On the Programme, chaired by K J White, were: Experimental Procedure and Communication A L Cameron Research Co-ordination K J White Mycology and Forest Pathology P Wright Fire Protection J K Riley Exotic Softwoods J E N Smith Forest Hardwoods K J White Genetic Improvement of Forest Trees in New Guinea A L Cameron Forest Tree Improvement – Kamarere J Davidson Tree Improvement – Hoop and Klinkii Pines L T Clifford

Formal presentations29 were scheduled and interspersed with local field visits.

My presentation on Kamarere was important at the time because it included worked up results from my official Tour of Duty at the ANU in Canberra that had ended on 4 April 1968. I presented a much more detailed account, especially on wood density, over two hours on the day than what was set out in the

28 Another PhD student, Mark Higgs, a year later, found similar patterns for wood density in E. regnans: See Higgs M L 1969 Genetic and environmental factors influencing commercially important wood properties of Eucalyptus regnans, a thesis submitted in partial fulfilment of the requirements for the Degree of Doctor of Philosophy in the Australian National University, Canberra. A later principal components analysis by me indicated the variation in wood of E. deglupta did vary systematically with height and distance from the pith, but this was difficult to visualize at the time from the patterns of two of the nine trees shown here.

29 Kevin White had the Department of Forests publish the Proceedings of this Conference eight years later (in 1976 and priced at K1.50!). He considered the information still had value for a wider circulation, as the original papers, which were made available only to attendees at the Conference, had become hard to source. The paper that was reproduced therein in 1976 as my contribution was written well in advance of the Conference and was similar to one prepared also in 1968 for a Conference of the Institute of Foresters Australia. My actual two-hour presentation in Bulolo in August 1968 was in greater detail and more up to date on the day.

paper prepared earlier that was handed out. I included illustrations on overhead transparencies and exhibits such as x-ray films, density traces and wood samples that were passed around the audience.

TREE IMPROVEMENT KAMARERE

I. INTRODUCTION

The genus Eucalyptus is poorly represented by naturally occurring species in the Territory of Papua and New Guinea. Of the six species present five belong to the dry savannah woodland. Eucalyptus deglupta (Kamarere) is the exception and forms part of the early seral forest in rainforest communities. E. deglupta is unusual in that it does not occur in Australia.

Kamarere is the major species of Eucalyptus planted in New Guinea up to the present time. Some years ago, it was decided that Kamarere might make a suitable pulping species when it was proved by Von Koeppen in 1958 that it would make a good pulp by the sulphate process.

The development of areas such as Vanimo and Wide Bay would require a large-scale reforestation movement on logged over areas to maintain operations on a sustained yield basis. A chip operation depends on a continuous supply of a large volume of wood to be economical. A two-ship export operation would require 120-150 million super feet [about 280 – 354 thousand m3] of woodand some 20-40 thousand acres [about 8 –16 thousand hectares] of land would be required to sustain an operation of this magnitude.

If we are considering entering into a project of this size it is obvious that we should do our utmost to provide the best possible product for the buyer. This can best be done by a detailed investigation of our present growing stock to find out its good and bad points and to introduce a programme to improve the desirable properties and to eliminate as far as possible the undesirable ones. The actual tree improvement programme was envisaged about 1966 at a time when the establishment of E. deglupta plantations in the Territory was at a low level and mainly experimental.

In Table one, which is attached to your copies of the paper, I have listed the areas of Kamarere that have been planted at Keravat over the past nine years.

TABLE 1 EUCALYPTUS DEGLUPTA PLANTINGS 1959-1968

Year 1959/60 Compartment and Logging Area 1. Little Vudal Station Keravat Area Established (acres) 133.5

1960/61 2. Little Vudal Keravat 83.6

1961/62 3. Little Vudal Keravat 25.0

1962/63 4. Little Vudal Keravat 45.5

1963/64 1. Vudal Keravat -

1964/65 5. Little Vudal Keravat 25.0

1965/66 4. Kamarere Keravat 56.9

1966/67 5. Kamarere Keravat 5.0

1967/68 6. Kamarere, 2. Vudal

Keravat * Planting trials, cuttings, prototype grafted seed orchard and other trials still to be planted in 1968. Trial areas*

Since 1948, when Kamarere was first established in a plantation at Keravat, only some 800 acres [about 325 ha] in total have been planted. This is only a drop in the ocean compared with what we now envisage. It is obvious that, in addition to the genetic programme, we need to take a critical look at the issues associated with the establishment of large areas of Kamarere.

Firstly, I am going to discuss how our genetic programme is coming along and later I’ll take a quick look at the production side of the issue.

II. THE GENETIC PROGRAMME

The first step in the development of a genetic programme is to assess the natural variation to be found in plantation stands of the species being investigated.

Alan Cameron made some preliminary investigations of basic density and fibre length on 19 trees 13 years of age in 1966.

In this work samples were taken at a height of 3’ 6’’ [1.07 m], in a north-south direction through the pith. Only a single sample 2½’’ [about 6.4 cm] along the grain and 1’’[about 2.5 cm] across the grain was removed from each tree.

Basic density was found to be fairly low in these young, fast-grown trees. Considerable variation was found among trees, showing promise for selection and breeding.

In the preliminary study on fibre length, Alan found it somewhat variable but the variation was fairly small.

The overall pattern of fibre length and density in trees is well known but detailed investigations are essential to enable comparisons of these characters between trees. If one is not certain of the within tree variation of a particular character, the information obtained from a single sample, say from breast height (or from 3’ 6’’ height with Alan’s work) cannot be applied to a selection programme, as we shall see later on.

The most reliable method of comparing even-aged trees is to compare estimates of fibre length and density derived from a number of measurements throughout each tree. This technique requires that a large number of sampling points be scattered throughout each tree and this high sampling intensity normally means cutting the tree down. In practical selection, sampling must be non-destructive so we must restrict the number and size of samples taken from each tree. How are we going to manage this?

We can overcome the problem by making a detailed examination of a small number of trees to find out the natural pattern of the character within the tree then use this knowledge to predict whole tree values from a limited sample. Also, where this limited sample is located within the tree becomes of great importance.

I have made a detailed assessment of fibre length and density in nine Kamarere from Keravat. Six of these were from a 19year-old plantation and three from a natural stand of unknown age near the Keravat River.

Each tree was cut down and a disc removed from ground level, breast height, 10%, 20%, 30%, 40%, 50% and 70% of total tree height. Pith to bark sections of these discs were sent to Canberra. At the ANU small sub-samples of wood were taken at 5, 25, 45, 65, 85 and 95% distance from the pith at each height level. These were placed in a 1:1 mixture of glacial acetic acid and 100 volume hydrogen peroxide and cooked for 4½ hours to obtain fibre separation. The fibres were mounted on glass slides and measured from the image produced by a projection microscope at 80-120 magnifications depending on the average length of the fibres.

XXXXXXXXXXXXXXX TRANSPARENCY – FIBRE LENGTH XXXXXXXXXXX I have here a diagram showing fibre length distribution in two trees. A plane running vertically in the north axis and extending from pith to bark is represented. (Explain details of diagram.) Fibre length increases from pith to bark in the normal way, but the longer fibre length values occur some way up the stem. How do we compare say this tree with the other? How do we rank them with regard to selection? In pulping the whole tree is used. The ideal way of obtaining a whole-tree fibre length estimate would be to pulp the whole tree and find out the fibre length in a well-mixed sample of its pulp. We cannot do this in practical selection without destroying the tree. A pure arithmetic mean of all the results would give us a result approximating 1.15 mm. This is also unsatisfactory as undue emphasis is placed on high and low values. What is needed is some kind of weighting system. Let us look at these two diagrams -

XXXXXXXXXXXXXXXXX CO-ORDINATES TRANSPARENCY XXXXXXXXXXX

These diagrams illustrate the weighting principle, which is the accepted method for calculating the average fibre length of the tree. If we take the jth disk and look at fibre length observations in that disk, the coordinates of FLij are Ri cms from the pith and Hj feet from the ground. Within the disk, FLij is assumed representative of the annular area Aij whose extremities correspond to the mid-point between successive observations. The weighted disk fibre length (WDFL) is calculated through the relationship: WDFLj = Σ(FLij x Aij)/Aj

This weighted disk fibre length is assumed representative of the fibre length in volume Vj of a cylinder of cross-sectional area Aj and extremities corresponding to the midpoints between successive disks. The weighted tree fibre length (WTFL) is determined by this relationship WTFL = Σ(WDFLj x Vj)/V

The information needed is fibre length (FL), total height of the tree, total radius of disks, height of the disk from the ground (H), and distance of the sample from the pith (R). These data were punched on cards and analysed on the ANU’s IBM 360 computer. For the nine trees these are the whole tree fibre lengths.

You might say that these fibres are short but anything over a mm is OK for a eucalypt. These values are derived from mean values of 100 fibres at each sampling position.

When we look at a frequency distribution for fibre length in a single sample the distribution is approximately normal and we have shorter and longer fibres present than the whole tree fibre length figures imply.

XXXXXXXXXXXXXX FIBRE DISTRIBUTION TRANSPARENCY XXXXXXXXXXXXXXXXX

The very short fibres will be lost in the screening process but the longer fibres will help the bonding qualities of the paper.

This diagram also shows the difference in fibre length between that at breast height and that at 30% height and between that at 2.5cms from the pith and 15 cms from the pith.

Next we turn to the issue of where to extract our limited sample from the tree (sample representativeness). Whereabouts must the sample be taken to give us our best estimate of whole tree fibre length?

Let’s go back to the previous transparency and look at some correlation coefficients –

XXXXXXXXXXXXXXX FIBRE CORRELATION TABLE TRANSPARENCY XXXXXXXXXXXXXXXXX

We can see from this table that fibre length in the breast height sample is only weakly correlated with whole tree fibre length. This as a sad state of affairs as breast height is a most convenient sampling position. To obtain a correlation significant at the 1% level we would have to go to ground level where we’ll have difficulties operating the sampling machine and where buttressing will be an issue, or, we will have to go up to about 20% of tree height. This would represent about 30 – 35 feet [about 9 – 11 m) above ground on the trees from which we are making our selection. Operating a chainsaw-like mortising machine that far from the ground would be no picnic!

We also come to a sticky end if we try to correlate the result at breast height with the result at 30% height (correlation coefficient R = 0.39 and not significant). In addition, to produce a pulp which would be comparable to that made from a softwood would require a much greater increase in fibre length than is currently being achieved in softwood breeding programmes. With E. deglupta we cannot really believe that any marked improvement in fibre length would be achieved as the natural variation is too narrow.

Thus, the combination of a non-representative breast height sample and the lack of any possibility of significant improvement of fibre length through breeding caused me to relegate selection based on fibre length to a secondary role.

Of the nine trees in this table –

XXXXXXXXXXXXXXX WTFL TRANSPARENCY AGAIN XXXXXXXXXXXXXXXXX

I would be inclined only to reject the one tree with a whole tree fibre length of less than 1 mm.

In the detailed study of wood density in the same nine trees I’ve used an X-ray technique, which is a relatively new idea for this type of work.

Small samples of wood extending from the pith to the bark were machined from the larger samples for each percentage height point. The end-grain surfaces were accurately machined using a specially modified router until they were 6.9 mm apart.

XXXXXXXXXXXXXX PASS AROUND WOOD SAMPLE XXXXXXXXXXXXXXXXX

These samples were placed on a sheet of X-ray film and irradiated with calibrated X-rays. If the thickness of the sample does not vary the intensity of radiation after passing through the sample solely depends on variation in density of the wood. Thus, an X-ray negative such as this is representative of wood density.

XXXXXXXXXXXXXXX PASS AROUND X-RAY NEGATIVE XXXXXXXXXXXXXXXXX

Being a negative the light-coloured parts represent higher density areas, that it the X-rays found it harder to penetrate the denser wood.

A linear relationship exists between the optical density of the X-ray negative and the density of the sample at the corresponding point. It is therefore sufficient to be able to record the variations in optic density across the X-ray negative of a radial wood sample to obtain, directly, the variation in density of the wood.

Having obtained the X-ray with its standards we analyse it with a recording microdensitometer. This machine gives a trace such as the one I have here.

XXXXXXXXXXXXXXX PASS AROUND DENSITY TRACING XXXXXXXXXXXXXXXXX

The height of the trace above a base line is proportional to wood density. By measuring the area under the trace for a short distance we can obtain an average value for that location. We can relate this value to the set of standard density values that we know accurately. I have done that for six points along this trace.

Using a number of these traces we can depict the pattern of density in the tree.

XXXXXXXXXXXXXXX TRANSPARENCY OF DENSITY PATTERN XXXXXXXXXXXXXXXXXX

As you can see the density pattern is not as straight forward as the fibre length pattern. (Explain diagram)

We can rank these trees for density by calculating weighted whole tree density (WWTD) in the same manner that we calculated whole tree fibre length.

XXXXXXXXXXXXXXX WEIGHTING PRINCIPAL TRANSPARENCY XXXXXXXXXXXXXXXXXX

We substitute density for fibre length in the first equation and weighted disk density (WDD) for WDFL in the second formula. Here are the figures for the nine trees –

XXXXXXXXXXXXXXX DENSITY FIGURES TRANSPARENCY XXXXXXXXXXXXXXXXXX

Excluding the three non-plantation trees, phenotypic variation in densities is evident, covering a range of some 20% at 8% moisture content.

For pulp manufacture, densities of around 27 to 30 lbs per cubic foot [432.5 to 480.6 kg/m3] have been advocated in the past. However, the present opinion of the major pulp and paper companies using eucalypts, including APM, is that one should look for a low-density species and select for the higher densities within that species.

In the selection of “plus” trees of E. deglupta I advocate we do not specify a density and select for it. We should aim to segregate our candidate trees into two or at the most three density categories, for example, low and high or low, medium and high. I think it would be best to sort into low- and high-density groups, ignoring those in the middle. We could consider two other special classes: a low extreme and a high extreme.

XXXXXXXXXXXXXXXXX DENSITY CATEGORIES TRANSPARENCY XXXXXXXXXXXXXXXXXX

Thus, we could get two possible outcomes, one with high density and one with low density. The resulting increased uniformity within a stand is likely to be of most importance in the future.

It seems likely that by looking at the wood properties of 100-150 plantation trees (the breeding population) we should end up with 30-40 good quality clones for our orchard (the propagation population).

Again, we come up against the issue of obtaining a representative sample from an individual tree without cutting it down. Let’s look at the correlation coefficients for density.

XXXXXXXXXXXXXXXX DENSITY CORRELATION TRANSPARENCY XXXXXXXXXXXXXXXXXX

The relationships between whole tree density and density at ground level and at breast height are statistically not significant. However, the correlation with 10% of total tree height is fairly good, being significant at the 1% level.

Therefore, our density sample must come from the 10% height level, that is, about 15 feet [4.6 m] from the ground. Although this will be more difficult than sampling at breast height, I think we can manage it using tall ladders

Wood density is the result of a complex of characters including cell wall thickness and vessel volume in eucalypts, thus the criterion is not straightforward. Maximum efficiency in breeding for density cannot be achieved until one knows what

influence the components have in determining it. Only correctly designed clonal or seedling progeny trials can indicate the extent to which the genetic component is affecting wood density.

We are presently cruising plantations looking for suitable “Candidate” trees. We are not paying much attention to volume production.

If you examine the height and diameter growth data derived from growth plots at Keravat and which I have graphed in Figure 1 attached to your papers you will see that growth potential is quite adequate for our needs.

XXXXXXXXXXXXXX TRANSPARENCY OF FIGURE 1 XXXXXXXXXXXXXXXXXX

The preliminary selection is being made for desirable external features, as these are easy to assess and also contribute to gross aspects of wood quality.

We are choosing trees that are straight and do not have marked fluting and spiral twists in the stem. Where possible we are selecting trees with minimum buttressing. It is likely that most of these features are largely genetically controlled and the form of the bole should be improved by selection.

Having selected 100-150 Candidate trees, we will apply our wood quality selection criteria. Samples will be removed from standing trees using a special machine incorporating a chainsaw motor power unit adapted to drive a mortising chain. This will give a pith to bark sample about 2’’ x 2’’ [5 cm x 5 cm] in tangential dimensions.

The wood property selection will be made firstly for density and a high selection differential will be applied. I would hope to discard at least two-thirds of the candidate trees in this initial stage. Density will be determined by the analysis of X-rays as I have described. A number of trees could be rejected on visual assessment of positive photographic prints of the X-rays, such as this one here.

XXXXXXXXXXXXX PASS AROUND POSITIVE PRINT OF X-RAY PLATE XXXXXXXXXXXXXXXXXX

The remainder will be analysed with the help of the recording microdensitometer to enable a decision to be made on the suitability of a particular tree.

A low selection differential will be applied to fibre length for reasons already discussed. The few trees with very short fibres will be rejected. We may have to eliminate another 5 – 10 trees at this stage.

By examination of X-rays from separate longitudinal and tangential irradiation of the wood sample, spiral grain may also be assessed.

XXXXXXXXXXXX PASS AROUND TWO X-RAY PLATES (EXPLAIN) XXXXXXXXXXXXXXXXXX

On this basis we may throw out a few more trees if we can afford to do so as spiral grain is supposedly strongly inherited and detrimental to most end uses of solid wood compared to use for pulp.

What else should we consider for the future genetic programme?

We must be very careful of just how much we include in our selection programme. If we try to extend our selection over too many characters our gains will be less and also the number of possible clones in the seed orchard would be reduced.

Cellulose content of the wood of E. deglupta may prove to be an important factor in pulping. Von Koeppen stated in 1958 that a sulphate pulp yield similar to that from other tropical species was obtained from 5-year-old plantation-grown E. deglupta; however, in 1965, Petroff, test pulping Kamarere grown in the Congo, found cellulose to be lower than that for all five other species of eucalypt tested at the same time.

A pulp industry operates on a large turnover and the profit margin per unit is relatively small. Thus, a very small increase in cellulose over lignin content could lead to a large increase in profit for the operating company. We haven’t yet looked at treeto-tree variation in cellulose content in E. deglupta grown in the Territory but I think we must do this. Perhaps it may pay to include it in the breeding plan in some way. This could lead to an increase in pulp yield from a given volume of wood but a general lack of heritability studies on chemical constituents of broadleaved species makes it difficult to predict any gain that might be achieved.

We hope to start off a seed orchard next planting season. We will probably use stock grafted by the “top-cleft” and “patch” methods and half-sib seed.

Kamarere has been routinely propagated by leaf and stem cuttings at Keravat from source material up to 6 months of age so far and several thousand cuttings of a number of unselected clones have been planted in a plantation near the Vudal River.

Experiments are continuing to try and find a method of routinely propagating cuttings from the crowns of mature trees. These involve variations of the mist spray regime and the application of different rooting hormones. We will see how we go!

Some experiments concerning seed orchard management are underway or proposed. Techniques to be used for breeding are being investigated. For example: the manner in which the inner operculum is shed, how the flowers open, and how and when to carry out emasculation.

A seed production study is underway at Keravat in an effort to ascertain how many trees will be needed in a seed orchard to produce a given amount of seed.

Seed collection from mature Kamarere is difficult because of its height growth and because it has a smooth branch-free trunk making it difficult to climb. We will be trying various combinations of lopping and tying down of branches to see if we can obtain a more compact tree crown and keep the seed crop low to the ground. The orchard will be laid out on a square or triangular grid so the possibility will exist in future to use hydraulic “cherry-pickers” like the ones used for picking fruit in Australia and elsewhere. I have seen one used by APM for pruning poplars, they are very handy, particularly the type that can be mounted on an ordinary wheeled tractor.

The collection of seed and scion material from select trees in the field has always been a problem in Australia and overseas. Australian experience has shown that a high-powered rifle fitted with a telescopic sight is ideal for this type of work. We are negotiating purchase of a .222 Remington rifle and a 3-9 magnification zoom telescopic sight for use at Keravat.

We hope to get some type of provenance study underway also. Attempts are being made to obtain small quantities of seed from selected trees in various parts of the Territory. It is also hoped to include seed from Indonesia and the Philippines but we have not had much success in that direction yet.

III. PRODUCTION STUDIES

In addition to the genetic program there is the need to determine appropriate economic procedures for the establishment and maintenance of large-scale plantations of E. deglupta with the primary objective of wood supply to the pulp industries. The use of clearing and burning for land preparation and the planting of tubed stock for plantation establishment should be reexamined. Away from the plantation area some type of planting on snig tracks and logged clearings will have to be used.

“Jiffy Pots”, a kind of pots made from compressed peat, have been used successfully for planting Eucalyptus species in many parts of Australia and overseas. Although not entirely appropriate in size, locally available Jiffy Pots have been used successfully to raise and plant out in the field thousands of cuttings at Keravat. It is hoped to obtain a quantity of peat pots of more appropriate dimensions and have a trial established in this year’s planting area at Keravat.

A planting trial was established some four months ago at Keravat to test various types of planting stock. Treatments include tubed stock controls, open rooted stock and stumped stock of various sizes. Some survival results are to hand for this trial. I have summarized these and they are given in Table 2 attached to your own copies of the paper.

XXXXXXXXXXXXX TRANSPARENCY OF TABLE 2 XXXXXXXXXXXXXXXXXX

Apart from the tubed stock, survival was disappointing. Peat pots were not included in this trial.

We still have a lot to do in this part of the programme. I have mentioned several avenues of approach in the last couple of pages of my paper. It will probably be several years before everything is straightened out.

This planting season, we are establishing a second planting trial, which will be similar to the one mentioned here but is planned to include stock potted in tall jiffy pots. A spacing trial is planned with 8 x 8’ [about 2.5 x 2.5 m], 9 x 9’ [about 2.75 x 2.75 m], 12 x 12’ [about 3.66 x 3.66 m] and 15 x 15’ [about 4.6 x 4.6 m] (control) spacing treatments.

Studies will need to be made on length of planting season in various areas, plant size, tending, response of growth and yield to fertilizer application and fertility of soils converted to pure plantations.

Identification and control of nursery pathogens, wood destroying fungi and insect pests will assume more and more importance as the programme progresses.

Well, that’s about all I have to say. Twelve to eighteen months ago about five minutes would have been sufficient to relate our total knowledge ofKamarere. I’ve discussed Kamarere here for more than two hours today and have by no means covered

all of our present knowledge. We know enough at this stage to predict that our programme will be successful, but just how successful remains to be seen!

Above left: Specimen collected by Frans Arenz from the Kigara River (Milne Bay/Raba Raba) and deposited in the Lae Herbarium. Above right: Specimen collected by L D Pryor 4 miles (6 km) up the Kutu River (Milne Bay/Raba Raba) and deposited in the Gauba Herbarium, Department of Botany ANU. Left: Specimen collected by Frans Arenz from the Kigara River (Milne Bay/Raba Raba) and deposited in the Gauba Herbarium, Department of Botany ANU.

Meanwhile, on Friday 23 August Professor Pryor accompanied by Frans Arenz flew by charter to Milne Bay and visited Raba Raba. Saturday and Sunday were spent inspecting and collecting specimens from natural stands of E. deglupta, on the Kigara River

and as far as four miles (6 km) upstream on the Kutu River. They returned to Port Moresby by charter early on Monday morning 26 August and Professor Pryor left for Australia later that afternoon.

I returned to Keravat on Sunday 1 September 1968. On arrival, I found a letter had been sent from the ANU offering me a Commonwealth Postgraduate Scholarship supplemented by the ANU out of research grant funds to study for a PhD30 in the Department of Forestry and building on the work already completed on E. deglupta towards my external Masters degree. However it was a requirement of study for a PhD under the Commonwealth Scholarship that the student attend ANU full time. This meant another prolonged absence from the Territory. Nevertheless I accepted the offer and advised the Department of Forests accordingly by memo dated 2 September.

Kevin White, then Chief, Division of Silviculture, wrote back on 9 September on behalf of the Department, stating the Department had no objection, but raised issues on whether field work would be undertaken in Papua and New Guinea during the period and asking what supporting field work would be needed from staff in the Territory. He also pointed out the necessity that work continued on the volume tables and productivity investigations.

Following the receipt of Kevin’s letter on 21 September I advised the Registrar, ANU that I intended to transfer my enrolment from the external Masters Degree in Forestry to that for a PhD degree and that I intended to arrive in Canberra in early 1969.

30 Under the rules then in place in the ANU Faculty of Science in the School of General Studies, a student with an Honours first degree was not required to have a Masters Degree as a prerequisite to enrolment for a PhD.