COLLECTIONS OF EUCALYPTUS CAMALDULENSIS DEHNH. AND EUCALYPTUS TERETICORNIS SM. SEED FROM NORTHERN AUSTRALIA IN 1977 FOR EX SITU CONSERVATION/SELECTION STANDS

by J.C. Doran & D.J. Boland

CSIRO Division of Forest Research P.O. Box 4008
Canberra, A.C.T. 2600
Australia

SUMMARY

During 1977, seed collections of the Petford, Katherine and Gibb River provenances of Eucalyptus camaldulensis Dehnh. and the Mt. Garnet provenance of E. tereticornis Sm. were made by the CSIRO Division of Forest Research for the establishment of ex situ conservation/selection stands. This article details these and other collections made during this period.

BACKGROUND

Previous collections

Australia-wide provenance seed collections of Eucalyptus camaldulensis Dehnh. were commenced in 1964. These collections were initially conducted by the late Mr. E. Larsen who also collected some provenances of the closely related E. tereticornis Sm. Much of the seed obtained was distributed internationally and subsequent field trials indicated that the best seed sources for many tropical countries were located within the Australian tropics. E. camaldulensis has been the more widely successful of the two species and better-known tropical provenances include Petford (Queensland), Katherine (Northern Territory) and Gibb River (Western Australia). The best known tropical E. tereticornis provenances are probably Mt. Garnet and Cooktown (Queensland).

The Seeds group of the CSIRO Division of Forest Research has made several collections in northern Australia since Larsen's original collections at Petford in 1964, and at Katherine and in the Kimberleys (Western Australia) in 1966. Five further trips were made to Petford in 1966, 1970, 1971, 1973 and 1975; one to the Katherine area in 1972, and two more to the Kimberleys in 1968 and 1972.

Performance of the Petford, Katherine, Gibb River and Mt. Garnet provenances as exotics

A brief summary of their performance as exotics is given below. The main sources of information were Lacaze 1970, 1977, many of the papers listed in Eldridge 1975 plus personal communications with visitors to Canberra and correspondents.

1. Petford: The Petford provenance has been consistently superior in the moister tropical savanna conditions. It is the favoured provenance for planting in the Congo, Madagascar, the median and northern Guinea zones of Nigeria and Rhodesia. It has shown superiority in recent trials in the sub-humid tropical and sub-tropical zones of Brazil, in Laos, in tropical lowland Mexico, and in Nicaragua.

   The Petford provenance is also ranked among the leading provenances in trials in India, the Philippines and Zambia and shows remarkable adaptability to be amongst the leading provenances in trials in Italy, Algeria, Greece and Turkey, although inferior to the Lake Albacutya (Victoria) provenance in each of these cases.

2. Katherine: This provenance has proved consistently superior in the more arid tropical savanna conditions. Katherine seed is favoured for the harsh dry conditions on the edge of Lake Chad and is the only provenance with satisfactory survival in the dry northern Sudan zone of Nigeria. It has also performed well in the moister parts of Nigeria when grown under non-irrigated conditions, and is the leading provenance in a trial at Dehra Dun, India.

   The Katherine provenance has shown encouraging early growth in provenance trials in the Congo, the savanna area of Brazil, in the arid part of the Negev in Israel, on semi-arid sites in Malawi, in tropical lowland Mexico, in Nicaragua, in Thailand, and under irrigation in Pakistan.

3. Gibb River: Seed has been distributed to over 40 countries since the initial collections were made at Gibb River in 1972 by J.W. Turnbull. The first provenance trials including seed from this collection were established during 1973 and because of their young age little has been published on the relative performance of this provenance.

   In recent trials in Thailand the Gibb River provenance has shown superior performance to other northern provenances including Irvinebank (Petford area) and Katherine. It is among the leading provenances in Nepal and Laos although in the latter case is slightly slower growing than Petford. The Gibb River provenance along with several other provenances from northern Australia have been selected for further trials in the savanna regions of Brazil.

4. Mt. Garnet area: Provenances of E. tereticornis from north Queensland have generally performed well in the humid to sub-humid tropical to sub-tropical zones of Africa, Brazil and Mexico.

   In the Congo, provenances of E. tereticornis from the Herberton and Mt. Garnet areas of north Queensland have done exceptionally well. In Nigeria good results have been obtained from a E. tereticornis source from Mysore, India and an unnamed provenance from north Queensland. In Brazil, provenances from the Cooktown area are of major interest, as is the case in tropical lowland Mexico where provenances from the Cooktown-Laura area of north Queensland gave similar growth and survival to northern provenances of E. camaldulensis at age 19 months. The Helenvale and Kennedy River provenances from north Queensland have proved to be amongst the most successful provenances in recent trials in Colombia.

Objectives of the 1977 collections

Because of the international importance of these northern provenances the FAO Panel of Experts on Forest Gene Resources recommended that some form of conservation should be undertaken to ensure their survival and the availability of seed. A grant of US$5 000 was made available to the CSIRO Division of Forest Research from the United Nations Environment Programme (UNEP) funds for the collection of seed of important provenances of eucalypts for the establishment of ex situ conservation/selection stands. High priority was given for seed collection of the Petford and Katherine provenances of E. camaldulensis. The Panel also recommended that seed be collected from a minimum of 25 well separated trees in each provenance, in order to avoid excessive narrowing of the genetic base.

SEED COLLECTIONS

Timing of Collections

The 1977 collections were made in two separate field trips to northern Australia. A two man field party carried out collections of E. camaldulensis in the Katherine and Petford area, and of E. tereticornis near Mt. Garnet, between 10 – 29 January, 1977; and two, three man teams made collections of E. camaldulensis in the Kimberleys and then in northwest Queensland in one major field trip between 9 July – 19 August 1977.

Conservation Collections

Collections were made from standing trees at Petford, Katherine and Mt. Garnet and from both standing and felled trees (18 trees) at Gibb River. A throwing rope with a weighted end or .308 inch calibre rifle were used to break off seed bearing limbs from standing trees. In general, seed was obtained from trees of average form, although a wide range of form class was included in each collection. The distance between seed trees varied from a minimum of 30 m to some kilometers. Most of the seed was extracted in the field shortly after the fruits had been gathered. Further information on the stands and individual trees can be obtained on request.

Individual trees at Petford, Katherine and Mt. Garnet only were mapped roughly and tagged with aluminium embossed labels at about 0.5 m above ground level. Trees at Gibb River were mapped roughly but not tagged. Photographs and herbarium voucher specimens were taken of all trees.

The total weight of seed collected from the Petford, Katherine, Gibb River and Mt. Garnet stands was 43 839 kg. Details of these collections including location, average size of parent trees, and seed data are given in Fig. 1 and Table 1. Tables 2 and 3 present a summary of meteorological data recorded at the nearest representative weather station in each case.

The trees of best form were undoubtedly those at Gibb River and Mt. Garnet. A photograph of an average tree in each stand is shown in Fig. 2, where the characteristic white bark of northern provenances of E. camaldulensis is clearly illustrated. Typically, the surface of the bark of trees at Gibb River, Katherine and Petford is covered with a fine, white powdery substance which can be readily rubbed off.

The remoteness of these stands restricts regular scientific seed collections and while their survival as nearly natural stands is not immediately endangered, in situ conservation measures would be difficult to implement. All provenances are located in grazing rather than in agricultural or forest lands. The Petford, Gibb River and Mt. Garnet provenances are on crown land leased for grazing while the Katherine provenance is on a reserve administered by the Northern Territory Reserves Board.

Additional Collections

Further small amounts of E. camaldulensis seed totalling 13 356 kg were collected during the period the field parties were involved with the conservation/selection stand collections. Details of the more important of these collections are indicated in Table 4 and Fig. 1.

SEED TESTING AND STORAGE

All seed collected was cleaned of all leaf and branch debris and fumigated with carbon disulphide. The seed was then tested for viability at 30°C and the moisture content of the seed plus chaff determined by the oven-dry-weight method. The results of these tests are shown in Table 1.

As the viability of E. camaldulensis seed can deteriorate over several years the seed collected has been placed in air-tight tins in a coolroom set at 3–5°C.

DETAILS OF SEED ALREADY DESPATCHED FOR EX SITU CONSERVATION/SELECTION STANDS

Seed of the Mt. Garnet provenance of E. tereticornis has been sent to the Forest Department, Republic of Zambia; Forestry Research Institute, Nigeria; the Centre Technique Forestièr Tropical, Republique Populaire du Congo; and the Fiji Pine Commission, Fiji. Seed of the Petford and Katherine provenances has been sent to the Forestry Research Institute, Nigeria and the CSIRO Division of Forest Research Regional Station at Darwin, Australia; and seed from Gibb River and Petford has been despatched to the Thai-Danish Pine Project in Thailand.

ACKNOWLEDGEMENTS

We wish to acknowledge the technical assistance of Messrs. E.G. Cole, J. Turner, W.J. George, D.A. Kleinig, M.J. Connell, P. Saardavut and J. Cusack in making the seed collections. Information on seed moisture contents was provided by Mr. Cole. Mr. Connell provided most of the information on seed viability. The map was produced by Mrs. M. Risby.

REFERENCES

Anon. 1975 ‘Climatic Averages Australia’ metric edit. (Aust. Govt. Publ. Serv. Canberra).

Eldridge, K.G. 1975 An annotated bibliography of genetic variation in Eucalyptus camaldulensis. Tropical Forestry Papers No. 8, Comm. For. Instit., Oxford.

Lacaze, J.F. 1970 Studies on the ecological adaptation of Eucalyptus. Operational report for 1970 on project No. 6; Document, 4th Session Committee on the Coordination of Mediterranean Forestry Research; FAO Joint Subcommission on Mediterranean Forestry Problems, Ankara, No. FO: SCM/FR 70/2/10, 25pp. (Fr.) (Unpublished).

Lacaze, J.F. 1977 Etude de L'adaptation ecologique des eucalyptus etude de provenances d'Eucalyptus camaldulensis. Project F.A.O. No. 6. Paper, 3rd FAO/IUFRO Consultation on Forest Tree Breeding, Canberra, 1977.

Table 1. Provenance location with some parent tree and seed data for three provenances of E. camaldulensis and one provenance of E. tereticornis

Table 2. Mean monthly rainfall data * (mm) for the Petford, Katherine, Gibb River and Mt Garnet provenances

* Information supplied by Bureau of Meteorology, Department of Science, Australia

Table 3. Monthly temperature and humidity data* for the nearest representative meteorological stations to the Petford, Katherine, Gibb River and Mt. Garnet provenances.

* Anon (1975)

Table 4. Provenance and seed details for other main collections of E. camaldulensis made during 1977

Fig. 1 Location of the 1977 E. camaldulensis and E. tereticornis collection sites. Collection sites are indicated by numbers and cross-referenced to provenance names in Tables 1 and 4.

Fig. 2 Photographs of an average tree of E. camaldulensis from: (a) Petford, (b) Katherine (with river levee bank on left hand side) and (c) Gibb River, and of E. tereticornis from: (d) Mt. Garnet showing typical tree form (associate tree species with dark bark consist of E. crebra, E. intermedia and E. polycarpa).