Forest Research Institute, Canberra
J.W. Turnbull
INTRODUCTION
The overseas demand for seed of eucalypt species from the tropical inland and tropical interior climatic regions of Australia is increasing and Eucalyptus camaldulensis, E. microtheca and E. alba are most frequently requested. The lack of settlement and the absence of forestry operations in these areas have resulted in seeds being unobtainable except by special expeditions. The 1972 expedition by staff of the Forest Research Institute's Seed Sub-section was jointly sponsored by the Forestry and Timber Bureau and the F.A.O of the United Nations.
OBJECTIVES
To collect seed of a wide range of tropical provenances of E. camaldulensis and E. microtheca and at least one bulk collection of E. alba from the Kimberley area of Western Australia.
To collect seed of other species listed as Priority 1 or 2 by the F.A.O. Panel of Experts on Forest Gene Resources if the opportunity was presented.
To collect botanical material and to take photographs for use in the Forestry and Timber Bureau Forest Tree Leaflet Series.
FIELD WORK
The field work occupied approximately ten weeks from 15 May – 20 July 1972. This period corresponded with the dry season in the tropics and also with the reported seeding time of E. camaldulensis.
The first section of the trip from Canberra to Darwin was supervised by Mr. D. Boland assisted by Mr. D. Kleinig and Mr. W. George. The remainder of the expedition was under the supervision of Mr. J.W. Turnbull, assisted by Mr. E. Cole and Mr. W. George.
CANBERRA - DARWIN
Seed collections began in the Flinders Ranges of South Australia with E.morrisii, E. gillii, E. camaldulensis and E. microtheca. From there the party travelled northwards through Marree and Oodnadatta and then turned eastward into the Simpson Desert to collect seed of Acacia peuce near the North Bore of Andado Station. Approximately 1,000 trees of A. peuce are found in this area with the only other species E. microtheca of poor form. The acacia is of impressive size, reaching 15 m. tall with a diameter to 60 cm. considering the very dry site.
Between Andado and Alice Springs the main species collected was the desert oak, Casuarina descaisneana. This is an impressive tree reaching a height of 14 m., dbh 90 cm., growing on deep loose red sands away from watercourses. In the Alice Springs area seed of E. camaldulensis, E. gamophylla and E. sessilis were obtained.
Small seed samples of several dry country species including E. normantonesis, E. pachyphylla, E. setosa, E. brevifolia were collected between Alice Springs and Katherine.
A small collection of E. camaldulensis was made in Chainman Creek west of Katherine and another at Ferguson River north of Katherine.
In general seed crops were light on E. camaldulensis and poor on E. microtheca. However, valuable collections of E. brevifolia, E. gamophylla, E. umbrawarrensis and Acacia peuce were made.
DARWIN-KIMBERLEY - ALICE SPRINGS
E. camaldulensis seed crops were light to moderate, but occasionally heavy on individual trees, in most of the north-western area. Collections of this species were made in the following river systems -
| Locality | System |
| Chainman Creek | Katherine River |
| Victoria River | Victoria River |
| Dunham River | Ord River |
| Ord River | Ord River |
| Mary River | Fitzroy River |
| Fitzroy River | Fitzroy River |
| Lennard River | Lennard River |
| Isdell River | Isdell River |
| Gibb River | Drysdale River |
| Drysdale River | Drysdale River |
| Stuart Creek | Inland |
| Yallagoorie Creek | Inland |
| Napperby Creek | Inland |
All provenances, with the exception of those of the Inland System, were of typical northern form of this species. This form has long narrow pale green leaves, a smooth white bark with no ‘stocking’, and a distinct axis. For tropical forestry purposes this form appears to be more desirable than the southern form.
The seed on E. microtheca had been shed before the collecting team arrived. It appears that April–May would be the best time to collect this species in the Kimberley area. The forester at Alice Springs suggested that January–February is the best time to collect the Central Australian provenances of E. microtheca.
E. microtheca is a very variable species, it ranges from a small sprawling shrub to a tall tree up to 24 m. in height. It may have rough bark extending to the smallest branches, have a ‘stocking’ of rough bark, or be completely smooth barked. It is a species which needs detailed taxonomic study. The best phenotypes observed were on the Fitzroy River at Fitzroy Crossing, W.A. Here the conditions for growth are close to optimum, plenty of soil moisture and a deep fertile soil with a high pH. The trees reach 24 m. in height and have a reasonably straight stem. They are the type with white smooth bark on at least the smaller branches, usually in the whole of the crown, and frequently extending down part of the trunk.
E. alba was seen growing in mixture with E. camaldulensis on the Lennard River and Manning Creek (Fitzroy System) in the Kimberley area. There were some particularly good specimens at Lennard River but there was no seed crops. This species appears to hybridise with E. camaldulensis. A small seed collection was made at Manning Creek but from a tree of poorer form than those at Lennard River.
Seeds of E. lirata, E. confluens, E. argillacea and E. jensenii were also collected in the Kimberley area but seed on species such as E. dichromophloia and E. houseana were too immature for collection.
SEED COLLECTED
The most important result of the expedition was the collection of the wide range of E. camaldulensis provenances. The large quantity of seed will ensure that research requirement for north Western Australian provenances of this species can be met for several years. The E. microtheca seed collection were disappointingly small but the information gained on the distribution, variation and seed ripening should facilitate the planning of future collections.
Seeds of the following species were collected. The figures in brackets refer to the number of provenances:-
E. camaldulensis * (25)
E. alba *
E. brevifolia * (2)
E. gillii **
E. jensenii (2)
E. morrisii v
E. miniata **
E. odontocarpa
E. pruinosa ** (2)
E. ptychocarpa
E. sessilis
E. trivalvis
Acacia peuce *
Erythrina vespertilio
E. microtheca * (7)
E. argillacea ** (2)
E. confluens
E. gamophylla ** (2)
E. lirata
E. mannensis
E. normantonensis
E. pachyphylla
E. patellaris
E. socialis
E. setosa
E. umbrawarrensis (2)
Casuarina decaisneana ** (2)
The total quantity of seed collected was 54 kg. of which 48 kg. was E. camaldulensis. The viability of the E. camaldulensis is very good and it is estimated that there is sufficient seed to raise 25 million plants.
* Priority I - F.A.O. Panel of Experts on Gene Resources
** Priority II- " " " " "
BOTANICAL MATERIAL AND PHOTOGRAPHS
230 botanical specimens were obtained, they include voucher specimens for the seed trees, specimens for the F.R.I. Herbarium and material for photographing for the Forest Tree Leaflet Series.
Photographs were taken in the field, illustrating tree form and bark of E. argillacea, E.bigalerita, E.blesseri, E.clavigera, E.collina, E.confluens, E.cupularis, E.houseana, E.lirata, E. odontocarpa, E.ptychocarpa, E.umbrawarrensis.
