Author: Susan Parsons
In the forests of Chile, in the locales of La Campana National Park and Cerro La Campana, the Soap Bark tree (Quillaja saponaria) is associated with the Chilean wine Palm (Jubaea chilensis). This felicitous link has determined our decision to write about both species in the one Tree Story for the National Arboretum Canberra. Quillaja saponaria will be planted in Forest 85.
Mark Richardson, botanical consultant to the Arboretum, has shared with us the signage information gathered for site. We have referred to the entry for Quillaja in ‘Trees and Shrubs in Canberra’ (2001) by Pryor and Banks and in
‘Horticultural Flora of South-Eastern Australia’ by Roger Spencer .
The trees grow up to altitudes of 2,000 metres in dry, poor soils. It can tolerate temperatures of -12C and is drought resistant. This attractive, medium sized evergreen tree has a rounded dense crown and thick ashy grey bark. The alternate, leathery leaves are sometimes slightly toothed. The white flowers are borne in summer in dense clusters of three to five, the lateral ones being male and the central ones female. The decorative fruits consist of five leathery follicles. In Canberra, Q saponaria has grown to more than 6m in height however it can reach 20m with a spread of 10m.
The inner bark, when reduced to a powder, is used as a substitute for soap, as it forms a lather with water. It is used as a food additive and an ingredient in pharmaceuticals, personal care products and fire-fighting foam. It has also been used as an additive for photographic films and foaming for drinks. The wood is used in cabinetry and scents derived from the tree are added to perfumes and cosmetics. The Andean people use it especially as a treatment for various chest problems.
The handwritten records of Canberra’s tree introductions at Yarralumla Nursery, which we researched in May 2012, show that Quillaja saponaria arrived:
“About 24 July 1947, seed ex Chile from W.AW. de Beuzeville, Forestry Commission of NSW 1oz Seed to be grown on half share basis”.
Seed was sown on “16/9/47, potted 11/3/48 number 55 and 5/11/4848 number 44. Transplanted on 16-10-48 number 25 position: Cotter?”
On 2.9.53 Q. saponaria came from Botanic Gardens Melbourne and on
20 November 1961 seed came from Forestry Commission NSW Pennant Hills.
In Bernadette Hince’s M.Sc thesis “A Pryor commitment: Canberra’s public landscape 1944-1958” there is a reference to Quillaja saponaria under infrastructure for landscaping and experimental work:
“Parks & Gardens exchanged plant and seed material with various Australian and overseas bodies. In July 1947, the New South Wales Forestry Commission sent Pryor seed forwarded from Chile (Laurelia aromatica, Maytenus boaria, Notofagus dombeyi, N. oblique, Podocarpus chiliana, Quillaja saponaria and Weinmannia trichosperma; A860/1, Dept Interior 1/12, 29.4.49.”
There is a small planting of Quillaja saponaria in Westbourne Woods in Canberra. The Woods are within the Royal Canberra Golf Course in Yarralumla, ACT and the trees grow in Plot 88 to the right of the 18th fairway at the golf club. On a Westbourne Woods walk led by FACTA (Friends of ACT Arboreta) in January 2011, those attending were fascinated to hear that the powdered bark lathers with water. A member of FACTA says, at a guess, he thinks the trunks of the trees are about 30cm in diameter and 6-8 metres tall.
The FACTA member also referred us to Quillaja saponaria growing at the Cotter Plots in Curtin, ACT. This was a trial planting ground for tree species in Canberra. In the substantial experimental area requested in 1945 by Lindsay Pryor, a limited number of introduced plants were established to see how they would fare over a period of years in the Canberra climate.
We understand the Quillaja trees at the Cotter Plots came from both seed and cuttings and photographs of these trees, taken in 2012 by John Turnbull, accompany this Tree Story.
Sue Johnston of Curtin also showed us specimens of Quillaja planted in the suburb. These plantings were from material left over from the Cotter Plots planting trials in the 1950s. There is a mature tree at the entrance to her property which is on a battle-axe block and three magnificent 30 metre specimens of Quillaja in the private garden of her near neighbours across the road.
Dr Roger Spencer says Quillaja saponaria growing at Geelong Bot Gdns is an old tree and the largest in the state.
Spencer also referred to a specimen growing in the Royal Botanic Gardens Melbourne, near the Herb Garden. He asked Curator of Arboriculture at the Gardens, Dan Thomas, to provide details of the tree. It is 22.4metres in height, canopy width at widest point is 15 metres and trunk at DBH (diameter at breast height) is 105cms.
In personal correspondence on 19 April 2012 Spencer said records of early tree plantings at RBGM were unfortunately destroyed. However he assumes the Quillaja was planted in Guilfoyle’s time when the medicinal area where it is growing was given a major renovation.
Emma De Landre, senior horticulturist at the National Arboretum Canberra, collected seed of Quillaja saponaria from Westbourne Woods on 4 April 2012. The seed is held in pods that look like star anise. The fresher seed germinates best so she emptied those pods by hand and cleaned the seed. The seed was soaked in water for 72 hours during which the fresh seed floated to the top.
De Landre sowed the seed on 7 April 2012. The seed trays were kept on thermostat-controlled trays overnight at 25C and then taken outside during the day to get maximum sunlight hours. The seeds began germinating on 11 April, 2012. The majority of seedlings were ‘pricked out’ into forestry tubes on 18 April and the remainder was done over the following fortnight in stages.
That process has produced 455 plants. Germination rate was almost 100% with the fresh seed and about 20% with the older seed (which De Landre sowed as an experiment). She also sowed some seed in a greenhouse outside and did not bring that in overnight. That batch germinated two weeks after the heated trays with about 50% germination rate even though it was fresh seed.
De Landre thinks, therefore, that mimicking the temperatures of where the species originates is good for germination, even though the species grows well in a colder climate, such as that of Canberra.
There are also 22 plants which were produced from cuttings by De Landre. The strike rate was low with the new growth cuttings striking best. Given the age of the trees at Westbourne Woods, and that they had not been pruned, there was not much new growth to use as cutting material.
At Yarralumla Nursery in Canberra there are 19 super tubes that were produced from seed collected in autumn 2011 at Westbourne Woods by Adam Burgess, curator of the National Arboretum Canberra.
This is the sole extant species in the genus Jubaea and is native to southwest South America, endemic to a small area of central Chile. The world record for Jubaea is at Kew Gardens and this is possibly largest individual specimen of an indoor plant in the world. It was raised c.1846 from seed collected in Chile by Thomas Bridges and transferred from the Palm House to the Temperate House in 1860 when its fronds were two metres in length. It was then transplanted sideways in 1938, a major task as the leaves were already touching the roof and brushing the glass. The palm flowered and fruited for the first time in 1950. It continued in good health despite the removal of the greenhouse roof during the 1970s and lack of heating during reconstruction.
The National Arboretum signage information from Mark Richardson shows its other common names as Coquito Palm, and (Spanish) Palma Chilena. Jubaea is named after King Juba II of Mauretania. The palm grows up to 1,400 metres above sea level in woodlands, almost exclusively on the steep slopes of dry ravines. It is classified as a threatened species.
Jubaea tolerates winter frosts and relatively cool summers. The sap produces a fermented beverage and can be boiled down to the syrup, miel de palma for cooking. However collection of the sap requires cutting down the tree and this harvesting has reduced its natural populations. Edible seeds are also harvested and the leaves are used to make baskets. Seed is slow to germinate, taking from 6 to 16 months.
The trunk of Jubaea has smooth grey bark. The dark green leaves are pinnate and up to 3-5m long. Flowers are produced on long, branched shoots and the oval fruit are bright yellow when ripe.
Stuart Read, Heritage Officer with the NSW Office of Environment & Heritage,
referred us to two historic specimens in Australia. A Jubaea chilensis was planted in 1860 in Adelaide Botanic Garden by then director George Francis. Later director, Richard Schombergk wrote of the palm, ‘The grotesque appearance of this palm renders it one of the most characteristic of the trees in the garden’. In 1896 visiting UK nurseryman James Herbert Veitch called it a ‘perfect specimen’ in ‘A Traveller’s Notes’, his privately circulated publication.
In 1893 Veitch visited Geelong Botanic Gardens in Victoria, noting its Jubaea chilensis was 18’ high. This iconic palm was planted c.1869 and it influenced the construction of the Raddenberry fernery in 1885 which was built to accommodate the height of the palm. The tree continues to grow and has been the symbol of Geelong Botanic Gardens’ logo since 1985 and it is entered on the Victorian Heritage Register.
Colin Mills, with his son Euan Mills, are both members of the Camden Park Nursery Group of which Colin Mills is convenor. This is a voluntary organisation dedicated to the refurbishment and maintenance of the colonial gardens at Camden Park. They operate under the umbrella of the Camden Park Preservation Committee, an independent body that oversees the maintenance of the property and which has a not-for-profit charitable status. They are a semi-autonomous, self-financing group, raising money from plant sales and from garden visits etc to pay for their activities. All monies raise go back into the gardens.
In February 2009, Colin Mills emailed to Curator of the NAC, Adam Burgess, the following information about the Jubaeas planted at Camden Park.
The first reference Mills could find was 1853, the year in which plants were given to the Royal Botanic Gardens in Sydney by William Macarthur. Mills thinks it is likely that plants were brought to Camden by John Bidwill around 1844 on his return to Australia from England by way of Rio de Janiero. This is speculation at present. Jubaea chilensis was introduced to England in 1843, a times of active exchange of plants between Camden Park and various individuals and establishments in England and Europe, so importation from England is also possible.
In 2009 Colin and Euan Mills had about twenty Jubaeas at Camden Park and almost all of them were well over 100 years old. With this Tree Story is a photograph of one of the Jubaeas taken when Adam Burgess and Mark Richardson visited Camden Park. On that occasion they collected Jubaea seed for the Arboretum and asked the Mills’ to propagate the seed from the trees planted at Camden Park.
In May 2012 Colin Mills emailed the following response for this Tree Story.
The seed of Jubaea was collected around Easter time 2009 from trees growing at Camden Park. They have about 20 trees from which to choose in the House Garden plus many more in the rest of the Estate (much of it now owned by the Elizabeth Macarthur Agriculture Institute). However all the seed came from the gardens, including from the tree in the photograph shared here. Collection was simple, picking up the miniature ‘coconuts’ from the ground.
The seed was soaked in buckets of water to macerate the outer coat and then it was cleaned with jets of water, followed by manual scrubbing. This was a laborious task. There was no specific stratification.
They sowed slightly more than 2,000 seeds and germination, while variable, took 7-8 months in a controlled environment until the plants were well established, about 18 months. Germination was something over 50%. Plants were delivered to Yarralumla Nursery in two batches of about 500 plants in March 2011 and February 2012.
Mills says there are mature trees within the Camden area, including several in Macarthur Park, Camden, which were donated by Elizabeth Macarthur-Onslow in 1908 (he thinks). There are also mature trees on the site of Ferguson’s Nursery at North Camden (Francis Ferguson was head gardener at Camden Park in the 1840s). Mills says these trees would certainly have come from Camden Park.
The Elizabeth Macarthur Agricultural Institute has also grown plants and planted them around the Macarthur's cemetery, which they now own. The order for the NAC was about as much as they could handle.
There are no records at Yarralumla Nursery showing an introduction of Jubaea to Canberra. The first stage of the planting of Chilean Wine palms at the Arboretum palms is in Forest 12 and the second stage is due to go in later in 2012. This could be the first plantings of the species in Canberra.