First visit to Keravat by Professor Pryor of the Department of Botany ANU

The all-cuttings plantation area at Vudal in early May 1968, photographed four months after planting. This plantation resulted from the first mass clonal propagation of E. deglupta by cuttings at Keravat. 1. The arrow indicates a line of one of the better clones that at the same time was represented by a relatively high number of genetically identical saplings. 2. Better growth was evident on portions of the site that were relatively still clear of weeds. 3. Growth was poorer on weedy locations, especially where there was already grass competition at the time of planting. 4. Vudal River with a much older routine plantation of E. deglupta on the left and logged over rainforest on the far bank.

First visit to Keravat by Professor Pryor of the Department of Botany ANU, 31 May – 1 June 1968

After our discussions in Canberra, Professor Lindsay Pryor15 of the Botany Department ANU was keen to inspect forests and plantations of E. deglupta at first hand. It was one of only a couple of species of Eucalyptus that up until that time he had not seen in the field. In Canberra he was posing the question to me that “was it a ‘true eucalypt’ in all its features?” He was eager to examine the systematic position of this species in the taxonomy of eucalypts. Maiden in 1910 had pointed out that it was not easy to establish the affinities of E. deglupta. Maiden noted the anthers were anomalous in that although their shape was “renantherous”, the lobes dehisced by separate slits.16 Blakely in 1934 placed E. deglupta and E.

15 Lindsay Dixon Pryor (26 October 1915 – 17 August 1998) was an Australian botanist noted for work on the taxonomy and vegetative propagation of Eucalyptus. He graduated from the Australian Forestry School with a Diploma in Forestry in 1936 and with the 1935 Schlich Medal. In September 1960 he became the first appointee to the Chair of Botany at the ANU. He retired in 1976, but remained at the ANU in several honorary roles until 1990. He was made an Officer of the Order of Australia in 1983 for services to botany. 16 Maiden J H 1910 A Critical Revision of the Genus Eucalyptus Volume II, Part 2 (Part XII of the whole work):80-81, Government Printer, Sydney.

schlechteri with E. raveretiana F Muell and E. brachyandra F Muell in series Myrtiformes of Section Renantherae.17 By 1953 Blake’s uncertainty about E. deglupta was expressed in his statement that the species seemed to be only loosely allied to Australian species of Eucalyptus. 18 Gauba and Pryor, in 1958, described a testa (seed coat) structure different from that of the Renantherae.19 Carr and Carr, in 1959, found the calyptra structure also not to be the same as that of the Renantherae.20 All of these observations had been made on dry herbarium specimens where the shape of these organs may have altered during the drying, treatment and preservation processes.

Following my return to Keravat from Canberra, Lindsay Pryor decided to visit Rabaul and Keravat after he had made a scheduled visit to the Solomons. Before Lindsay’s arrival, I obtained some fresh bud and flower material and took it to the LAES where I was permitted to use a microscope with a camera attachment for a detailed examination and take photographs of early flower bud development and morphology of the anthers.

Early flower bud development in E. deglupta. Left: Outer bud bract whorl enclosing inner bud bracts (x15). Right: Developing flower buds inside the whorl of inner bracts, most of the outer bracts having been shed (x 10).

17 Blakely W F 1934 A Key to the Eucalypts, The Workers Trustees, Sydney. Reprinted by the Forestry and Timber Bureau, Canberra, 1955. Section Renantherae later became equivalent to Subgenus Monocalyptus. 18 Blake S T 1953 Studies on Northern Australian Species of Eucalyptus, Australian Journal of Botany 1(2):185-352. 19 Page 27 In Gauba E and Pryor L D 1958 Seed coat anatomy and taxonomy in Eucalyptus. Proceedings of the Linnaean Society of NSW 83:20-31. 20 Carr D J and Carr S G M 1959 Floral morphology and taxonomy of Eucalyptus, Nature 184:1549-1552.

Left: Flower bud primordia developing inside the whorl of inner bracts (x 10) Right: Outer calyptra being shed from very young flower buds, leaving scar tissue in a ring around the bud. Inner bracts have also all shed by this stage (x 5). Typically from three to seven of these buds would be retained to form the flower umbellaster in this species.

Anthers of E. deglupta are shown under a microscope at high magnification (x 70). Shape is a rounded oblong, almost earlike when seen from the side. Appearance is a translucent pale yellow. Actual average size is about 0.25 mm wide by 1 mm long. The flexible attachment point near the middle of the back of the anther and an adjacent glossy terminal gland are illustrated at left, and one of the two longitudinal slits that occur along opposite sides of the anther, through which pollen has been shed, is shown on the right. The slits remain separate throughout their length. These images confirm the anthers of E. deglupta are not like the distinctly kidney-shaped examples typical of the Renantherae.

Whether a species has one or two calyptra during flower bud development is a diagnostic character used in the classification of eucalypts. E. deglupta definitely has two, an inner and an outer calyptra. The outer calyptra is discarded very early in the life of the developing bud, leaving an annular scar around its circumference.

Anther morphology also is an important diagnostic character in eucalypts. The anthers in E. deglupta are dorsifixed. That is the filament is attached loosely to the back of the anther, such that the anther is free to swivel (also referred to as “versatile”). Longitudinal slits open on each side through which the pollen is shed. The fresh material examined revealed the anthers were not really the definite kidney shape of the Renantherae at all. The slits were mainly parallel to each other on each side of the anther and did not converge to meet at one end as in the Renantherae.

Fresh bark was also examined. The bark of E. deglupta was found to be non-aromatic. That is, it does not contain oil glands and it does not have the typical eucalyptus smell when crushed. The leaves however do have oil glands and the typical eucalypt smell, but the oil content is low.

On Friday afternoon 31 May 1968 Gloria and I travelled by road in to Rabaul to meet Professor Pryor at the Rabaul airport and take him to his Hotel. We stayed in Rabaul overnight and set out for Keravat with Professor Pryor at 7.30 AM on the Saturday. The whole day was spent at Keravat where Lindsay was briefed on my grafting and cuttings work on E. deglupta and he inspected grafts and cuttings in the Keravat nursery, trees in the 1948 plantation, and plantations of E. deglupta along the Kalabus Road. After lunch with us at our place, Lindsay and I made the trip to Vudal Compartment 2 to inspect the E. deglupta cuttings plantation, then just five months old. Professor Pryor was taken back to Rabaul by road, arriving at 8PM. He spent the night of 1 June 1968 in Rabaul and took the plane out the next morning.

Left: Professor Pryor inspects a cutting of one of the best E. deglupta clones in the, by then, five-month-old clonal cuttings plantation at Vudal on 1 June 1968.