News and Events

Botanical Buzz - Olive Tree

Wednesday, May 22, 2013

The Olive Tree (Olea europaea) is a species of small tree in the ancient family Oleaceae which includes lilacs and jasmine. It is drought, disease and fire-resistant, and can live for thousands of years.

The olive tree is grown for olive oil, fine wood, olive leaf, and the olive fruit. It is the oldest cultivated tree in the world. The earliest evidence for the domestication of olives is about 7000 years old and comes from the archaeological site of Teleilat Ghassul in Jordan. 

Olive oil was one of the main exports of the ancient city of Ebla in Syria which at the height of its power (c. 2600–2240 bc) dominated northern Syria, Lebanon, and parts of northern Mesopotamia. 

The olive tree is one of the plants most often cited in western literature and has served a purpose in many different religions and cultures throughout history. It has been a symbol of peace, life, wisdom, glory and fertility. Its association with peace and victory derive from the customs of Ancient Greece. Olive wreaths were worn by brides and awarded to Olympic victors.

These days olive oil is used in cooking, cosmetics, pharmaceuticals, and soaps and as a fuel for traditional oil lamps. Extra virgin olive oil is the most highly regarded of the different types of olive oil. Its fine fruity flavour and aroma make it a valuable ingredient in salad dressings and dips.

Olives are one of the most extensively cultivated fruit crops in the world. They are a naturally bitter fruit which need to be fermented or cured to make them more palatable. The most flavoursome olives are those which have been cured using traditional methods such as soaking them in brine. 

An olive tree can be found in the Sensory Gardens next to the arbour and there is an Olive Grove next to the Cenotaph in Victoria Park.

by Ian McAlister and Karen Hagan

Botanical Buzz - The Wollemi Pine

Wednesday, May 22, 2013

The Wollemi Pine (Wollemia nobilis) is one of the greatest botanical discoveries of our time. It was found in 1994 by David Noble, an officer with the NSW National Parks & Wildlife Service, in a remote narrow, steep-sided sandstone canyon in the extremely rugged Wollemi National Park, New South Wales. 

It is an evergreen tree reaching 25-40 m tall. The bark is very distinctive, dark brown and knobbly, resembling the Coco Pops breakfast cereal. The leaves are flat, 3-8cm long and slightly spiky to the touch.

It is not a true pine but rather is related to Agathis and Araucaria in the family Aracariaceae. Its closest relatives include the Kauri, Hoop, and Bunya pines all of which may be found in the Oasis Valley dry rainforest at the Dubbo Regional Botanic Garden.

Fossils resembling and possibly related to Wollemia are widespread in Australia, New Zealand and Antarctica, but Wollemia nobilis is the sole living member of its genus. The last known fossils of the genus date from approximately 2 million years ago. It is thus described as a living fossil and was certainly around during the time of the dinosaurs.

Fewer than a hundred trees are known to be growing wild. It is very difficult to count them as most trees are multi-stemmed.

Genetic testing has revealed that all the specimens are genetically indistinguishable. This suggests that at one point the wild population was greatly diminished leaving only a few survivors. Lack of genetic variation detrimentally impacts upon the ability of a species to evolve and adapt to changing environmental conditions through natural selection.

To protect the rare wild-growing trees from being damaged or stolen, their location has been kept secret from the public and a successful commercial propagation program instigated to make the plant widely available for purchase.

Sadly, despite all precautions in 2005, the wild-growing trees were found to be infected with Phytophthora cinnamomi. It is suggested that this virulent water mould may have been introduced by unauthorised visitors to the hidden site.

There are two Wollemi Pines in the Dubbo Regional Botanic Garden; one in the Oasis Valley and another in the Sensory Garden.

by Ian McAlister and Karen Hagan

Botanical Buzz - Persimmon

Wednesday, May 22, 2013
"I am going to be victorious because a large persimmon has fallen into my hand," boasted the Seventeenth Century Japanese feudal shogun Tokugawa Ieyasu. 
An omen based on a real event or a figure of speech? Did a persimmon really fall into the shogun’s hand or is he referring to a major strategic advantage that has come unexpectedly his way? In any event, the swollen golden fruit of the Japanese persimmon, redolent with scent and sweetness is a rich prize indeed. 

Japanese persimmons taste best when they have been allowed to rest and soften for a few days after harvest. A ripe fruit will smell fragrant. The delicious, soft, jelly-like consistency is then best eaten with a spoon. Unripe fruits are astringent and bitter.

The Japanese Persimmon (Diospyros kaki) in the Japanese Garden (Shoyoen) of the Dubbo Regional Botanic Garden has a special significance. Dubbo’s Japanese Sister City, Minokamo is famous for its dried persimmons (Dojou-Hachiyagaki). They were offered as gifts to the imperial court during the Heian period and are now an internationally famous local specialty.

Making a traditional Dojou-Hachiyagaki requires considerable patience. It is a labour intensive process that can take several weeks. First the fruit is harvested and peeled. A small piece of peel is left on the bottom of the fruit to stop the sugary syrup dripping out. The fruit is then hung on a string until it develops a skin. During autumn the thousands of golden drying persimmons hanging in the breeze are a spectacular sight in Minokamo.

Once the drying fruit has developed a skin, it is massaged every 3 to 5 days for several weeks to break up the hard inner pulp. Eventually the sugars will come to the surface of the fruit giving it a white bloom.

The persimmons on the tree in Shoyoen are still green but they will soon swell into beautiful, golden fruit.

by Ian McAlister and Karen Hagan

Botanical Buzz - Silk Floss Tree

Wednesday, May 22, 2013

In the myths of early societies all of nature was infused with spirits or a “divine presence” and trees often had a special significance.

A sad yet beautiful Bolivian myth surrounds the extraordinary Silk Floss Tree (Ceiba speciosa).
The Silk Floss Tree is a deciduous tree native to the tropical and subtropical forests of South America and belongs to the same family as the baobab and kapok. It earns its name from the large amounts of fibrous material reminiscent of cotton wool or silk, which surround the seeds inside the 20cm long seed pods. This fibre was once used as stuffing for pillows and mattresses. 

When the tree is young, like the specimen in the Sensory Garden, it has large conical spikes on its green trunk. The chlorophyll in the trunk allows the tree to continue to photosynthesise during its leafless period and it is speculated that the large spikes protect it from grazing animals. 

As the tree matures, the trunk will develop a bulge, the bark will turn grey and the spikes may fall off. Fortunately these disturbing similarities to the stereotypical characteristics of human middle age stop there!
The Silk Floss Tree was chosen for the Sensory Garden because it is one of the most beautiful flowering trees in the world.

According to the Bolivian myth the prolific, large pink and white flowers are the form taken by the spirit of a beautiful woman, Araverá when she wants to be with her husband, Colibri the hummingbird god. Araverá died in the tree after taking refuge there (thus the bulge) to give birth to her son. Evil spirits were trying to kill her because her unborn son was destined to punish them for their wickedness. Her son lived to fulfil the prophecy.

The Silk Floss Tree may be found near the red gates of the Sensory Garden.

by Ian McAlister and Karen Hagan

Botanical Buzz - Lemon Verbena (Aloysia citrodora)

Wednesday, May 22, 2013

During the eighteenth century the sweet smelling Lemon Verbena (Aloysia citrodora) was one of the few survivors of a prized botanical collection deliberately sabotaged in an infamous politically motivated stratagem.

Competition between European countries to collect botanic specimens of new exotic plants was intense. In addition to giving prestige to botanic gardens, the new plants were highly prized for their possible commercial value.

In 1777 ill-fated French botanist, Joseph Dombey was sent to South America to collect new plants for cultivation in France. 

His first shipment of botanic specimens was stolen on its way to France by the British. This act of piracy became an international scandal – the “Dombey Affair”.

A second shipment comprising artworks of rare plants was erroneously confiscated by the authorities in Peru and given to Spanish botanists.

Imagine Dombey’s despair when his third shipment, which he was accompanying back to France, was impounded on arrival in Cadiz and he was thrown in gaol. Dombey was released when he agreed not to publish his research before the Spanish but his priceless collection had been allowed to rot.

The Lemon Verbena survived but it was not new to Europe. Spanish botanists already had a specimen and had named it Aloysia after the wife of King Carlos IV of Spain.

The unfortunate Dombey died after being unjustly incarcerated in a Montserrat prison during another adventure but his contribution to botany was recognised posthumously when a genus was named after him, Dombeya.

Lemon Verbena now has a special place in the Sensory Garden where everybody may enjoy its scent by gently passing their hands through its leaves.

by Ian McAlister and Karen Hagan

Botanical Buzz - Niwaki and the Japanese Black Pine

Thursday, January 31, 2013
Visitors to Shoyoen at the Dubbo Regional Botanic Garden are often intrigued by the bamboo poles and black ropes constraining the limbs of the Japanese Black Pines (“Kuromatsu” in Japanese). 
The trees are being sculpted into idealised shapes using the Japanese horticultural art form “Niwaki”. Niwaki (“garden tree” in Japanese) are highly asymmetric and yet beautifully balanced. The final shape will depend upon the individuality or “essence” of the tree and the ambience desired for that part of the garden.

To recreate a “tranquil wilderness” within the Japanese garden, Niwaki are sometimes fashioned into miniature caricatures of the windswept pine trees found on the Japanese coast.

Niwaki shares some characteristics with Bonsai. Both art forms use a combination of techniques including specialised pruning to create trees which have the appearance of much older, venerable specimens. The foliage is encouraged by careful pruning to become artificially dense. This gives greater definition to the final shape of the tree. 

Japanese gardens use many different tree shapes but the most common are the tama-mono shape and the moyogi shape. The low, simple, rounded tama-mono shape occurs throughout Shoyoen. The Japanese Black Pine is often sculpted into the moyogi shape which is characterised by an S-shaped trunk, cascading branches and an open, upright form. 

It takes many years to learn how to sculpt a Japanese Black Pine and many more to create a beautiful tree which fulfils its purpose in the garden. Pruning skill and knowledge of the underlying principles are interdependent. 

When the Japanese Garden designer, Katsuoki Kawahara was asked how long it takes to produce a pine tree that appears to be 100 years old, he replied, “One hundred years!" 

Council staff use Niwaki techniques to sculpt the Japanese Black Pines in Shoyoen under the guidance of expert Japanese gardeners. Three Japanese gardeners are currently visiting Shoyoen from Minokamo to share their horticultural knowledge with council staff and the Friends of the Dubbo Regional Botanic Garden.

by Ian McAlister and Karen Hagan

Botanical Buzz - Suikinkutsu at Shoyoen

Monday, December 31, 2012

The Dubbo Regional Botanic Garden is growing and changing so rapidly that in all the excitement it would be easy to miss the subtle details that make it a very special place.

Upon close inspection many of the plants and features in the garden reveal surprising and delightful characteristics. One such feature is the suikinkutsu, the Japanese water harp near the Chakoya (Japanese Tea House). 

The mysterious, melodic suikinkutsu cannot be seen, only heard. It is constructed using a large empty ceramic pot, buried upside down in the ground to create a resonant chamber. When water drips into the chamber through a hole in the top, the pot rings like a bell, making a sound resembling a Japanese zither (koto).

The suikinkutsu has been installed next to the chouzubachi, a traditional Japanese stone basin for washing hands before the tea ceremony. Water splashed from the basin drains through the stones at the base into the suikinkutsu causing it to quietly chime. 

The famous tea ceremony teacher, Kobori Enshu who lived during the Edo period (1603-1867), is usually credited with inventing the suikinkutsu and had one in his garden. After the Edo period, the instrument was largely forgotten until it experienced a revival in popularity during the late twentieth century.

When you next visit Shoyoen (the Japanese garden) find the chouzubachi outside the Tea House, gently splash water onto the stones and listen closely for the soothing and relaxing sound of the suikinkutsu.

by Ian McAlister and Karen Hagan