FRIENDS of the AUSTRALIAN NATIONAL BOTANIC GARDENS

The cover of this month's Newsletter shows Corunastylis aff. sagittifera, an undescribed
Midge Orchid, one of the lesser known ACT orchids.

Photographed by Tony Wood and click here for his description

 

This is a sample of our Newsletter's diverse and interesting content.
Join the Friends to receive your own full copy of each issue.


November, 2007
  
Welcome to our New Patron
Some Lesser Known ACT Orchids
Living Collection Review
Araucaria cunninghammii
Welcome Stephen
Boobook ... Mopoke ... Moreport ...
Diseases in the garden and Gardens
Growing Friends
Friends Briefs
  

Welcome to Her Excellency Mrs Marlena Jeffery
our new Patron

The Friends are delighted to announce that Her Excellency Mrs Malena Jeffery has accepted our invitation to become Patron.

Photo : Murray Fagg

Some of our members met Mrs Jeffery when she officially opened the Rock Garden Shelter in March this year. At that time she spoke of her great affection for the Botanic Gardens and we look forward to welcoming her again to other events in the Gardens.

Our retiring Patron, David Young, has been Patron since 1995. Earlier, in September 1990, he was a member of the committee which initiated the creation of the Friends. Subsequently, he encouraged the formation of a guides service for the Gardens and, in 1992, was involved in interviewing and selecting the first intake of guides. Though he has many commitments in the gardening world, with writing, broadcasting and travelling, David has supported the Friends generously through presentations of talks and participation in Friends events. The Friends Council is very grateful for David's support over these years and hopes that we will see him at Friends' events into the future.

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Some Lesser Known A.C.T. Orchids

Tony Wood
                                                                          
All photos by Tony Wood      

The blue Waxlip Orchid (glossodia major), the yellow Donkey Orchids (Diuris species) and the white to pink Finger Orchids (Petalochilus species) will be a familiar sight to those who venture into the Canberra nature reserves in spring. But there are many other terrestrial orchids that are not so well known, some that flower at other times of the year, some that are very localised, and some that are rare and endangered. The following is a selection of the less commonly encountered orchid species to be found in the A.C.T.


Thelymitra cyanea
,

known as the Veined Sun Orchid, flowers in summer in sphagnum bogs at high elevations, often forming small colonies. The distinctively veined flowers open freely in warm weather

 

Arachnorchis actensis,

is Canberra's own spider orchid. A very localised species known only from a few colonies on
Mt Majura and
Mt Ainslie. Flowering is in spring. Considered to be critically endangered.


Corunastylis aff. sagittifera,

is an undescribed species of Midge Orchid that occurs on Black Mountain. It is quite widespread, but only seen in small numbers in dry, more open habitats. Flowering is in early autumn. Easily overlooked because of its small size.

 

Sullivania minor

flowers in late spring. The flowers are yellowish green to reddish brown and bear a resemblance to a flying duck, hence the common name of Small Duck Orchid. It is locally common on Black Mountain on forested ridges and slopes. A small orchid that is easily overlooked.

Oligochaetochilus hamatus

is not common in the ACT. The flowers are greenish brown and the lower sepals have a hooked appearance, giving the orchid its common name of Hooked Rustyhood. It can be found in open forest, often among rocks. Flowering is in sping.




 


Cyrtostylis reniformis

is a small orchid with a ground hugging, heart shaped leaf. Known as the Gnat Orchid, it flowers in early spring. It often forms quite extensive colonies. It is quite widespread and reasonably common, and can be found in several locations on Black Mountain. The labellum is broad and pinkish brown in colour. Often overlooked because of its small size

Hymenochilus bicolour

is one of the spring flowering Midget Greenhoods. The pale green labellum has a dark greenish black appendage that gives the orchid its common name of Black-tip Greenhood. It is quite common and widespread, growing in forest, woodland and grassland habitats.

 


Bunochilus umbrinus

is one of the tall leafy green-hoods. A recently described species, it is only known from a few localities, including several colonies on Black Mountain. It grows on sheltered, southern facing slopes. Flowering is in late winter to early spring.





Prasophyllum canaliculatum

is one of the many species of Leek Orchid that flower in summer. In the ACT it is only known from a locality where it grows among grass tussocks adjacent to swamps. An endangered species whose biggest threat is probably from the activities of feral pigs.

 

 

Lyperanthus suaveolens

is known with certainty from only three colonies in the ACT, two of which are on Black Mountain. It is found in open forest, often in grass tussocks. The flowers, which appear in spring, are long-lived. The common name is Brown Beaks.

 

 

Corysanthes incurva
commonly known as the Slaty Helmet Orchid, is a tiny orchid found in moist sheltered sites in open forest. The single dark purple flower, about 1 cm across, is strongly hooded and sits on a small rounded leaf. The labellum is fringed with short incurved teeth. It often grows in dense vegetative colonies, with only a very small proportion of flowering plants. Flowering is in late winter/early spring. Easily overlooked because of its small size, with the plants often covered by leaf litter.

 

Acianthus collinus
is one of the so-called Mosquito orchids. Only recently found in the ACT, and now known from three colonies on Black Mountain. It has a small heart-shaped leaf that is purplish underneath. The flowers are pinkish with a somewhat darker labellum. It can form quite extensive vegetative colonies. Unusual in its winter flowering habit.

 

 

 

 
  

Living Collection Review

Joe McAuliffe and Anne Phillips

Climate change is an issue of global significance which represents a challenge and an opportunity to the Australian National Botanic Gardens. Practically, the ANBG has to be as efficient and effective as it can be3 in both energy and water use, as an example to the national community and to other gardens. Strategically, the Gardens has to consider what its role is and, specifically, what the role of the living collection is, in contributing to national climate change adaptation efforts. The Gardens' work in horticultural information and research, ex-situ conservation of threatened species and community awareness are some of the area where the ANBG could make significant contributions.

The complexity of the living collection and its relevance to today's political and environmental climate are increasingly coming under the spotlight. As an element of the strategy to position the ANBG as a leader in climate change adaptation, the Gardens has commenced a substantial review of its living collection to better define its role in relation to climate change and drought (the immediate physical impact of climate change).

The first step in this process is a census of the ANBG living collection. This entails a blitz on the stocktake process, which usually takes three to four years. Nursery staff are currently on loan to Plant Records to speed up this process. It is estimated it will be completed in one year when the collection's actual holdings in the Gardens will be realised. From this information the ANBG will be able to make assessments of the collection and to develop and implement a living collections policy that will provide the Australian public and scientific community with a nationally relevant collection and thematic displays.

The review may also enable new projects to be developed at the ANBG. Alpine communities have been identified as plant communities likely to be threatened by climate change. With the proximity of the ANBG to alpine areas, it may be that ANBG is well placed to take on national responsibility for ex-situ conservation of threatened alpine plants.


Greg Flowers, inventor, with the stocktaking
pulpit he made attached to a trolley

Photo : Tim Mulcahy



Joe McAuliffe and Craig Cosgrove collect Pratia serrepens
  seed from the icy waters of Mt Kosciuszko National Park

 

Staff have already commenced collections from Alpine Feldmarks and Short Alpine Herbfields in Kosciuszko National Park in conjunction with climate change experts and NSW NPWS, in order to assess feasibility of this as a major ANBG project. (See also Newsletter No. 55 March 2007 or click here to view it in Archives).


Little is known about alpine seed germination and many species have proved difficult to germinate and propagate in the past - this could also form a major contribution to climate change studies.

In order to make significant investment in this project, an ex-situ conservation strategy needs to be developed for target species which will address seed collection and banking requirements as well as propagation techniques and living collection requirements. ANBG staff are keen to be involved in this work of national significance and are working towards developing this strategy with partners.

When walking round the Gardens you can see the results of this stocktake process. A red paper tag means the plant has lost its metal tag or has had its name changed and needs a new tag. A yellow ribbon means the plant has to be removed because it was never part of the collection, usually a seedling, etc. A blue metal stake in the ground means that plant needs a flowering specimen collected for the Herbarium

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Araucaria cunninghamii
Hoop Pine

John Turnbull

An entrant in the 2007 Bernard Fennessy
'What's in a Name?' award

Photo : John Turnbull

From dinosaur tree to producer of paddle pop sticks, the Hoop Pine, Araucaria cunninghamii Alton ex A. Cunn., is very much at home in the Australian National Botanic Gardens. It can be seen thriving in the rainforest gully (Sections 61, 62, 64) and the conifer area adjacent to the caged Wollemi Pine in Section 78. (Editors' note : The Wollemi Pine has since died - see Friends Briefs).

This large, elegant conifer belongs to the Araucariaceae, a widespread and abundant family on the super-continent Gondwana, long before Australia broke away and began its drift northwards. Araucarian fossil plants go back over 100 million years to the early Cretaceous age and ancestors of these trees certainly co-existed with dinosaurs.

These days the Araucariaceae family includes Bunya Pine (A.bidwillii), Kauri Pines (Agathis species) and the recently discovered 'living fossil' Wollemi Pine (Wollemia nobilis). Species in the genus Araucaria grow in Southern America, New Guinea and some Pacific islands as well as in Australia. So not surprisingly the name 'Araucaria' is derived from 'Arauco', a province in southern Chile where Araucaria araucana, the Monkey Puzzle tree, is native. Some botanists believe the derivation is from 'Araucanos', a tribe in Chile formerly inhabiting the region where the first Araucaria species was discovered.

In Australia this tree is commonly referred to as 'Hoop Pine' and occasionally as 'Moreton Bay Pine' or 'Colonial Pine'. Young trees have attractive reddish brown to coppery bark that splits and peels in horizontal strips. Old trees fall eventually to the forest floor where their soft coniferous wood decays rapidly and all that remains are hoops of bark. These hoops have inspired the tree's common name.

Early in the nineteenth century Englishman William Townsend Aiton (1766-1849) published the name Araucaria cunninghamii. Aiton gained distinction as a landscape gardener and was the Royal Gardener at Kew for almost 50 years from 1793. He was also one of the founders of the Royal Horticultural Society. The specific name, 'cunninghamii', honours Allan Cunningham (1791 - 1839) who was an explorer and one of Australia's great early botanical collectors. Cunningham studied law and initially worked in conveyancing. He soon became dissatisfied with this profession and found employment as the assistant to William Aiton at Kew Gardens. It was Aiton who recommended Cunningham to Sir Joseph Banks and helped him secure an appointment as a botanical collector.

After a short time collecting plant specimens in Brazil, Allan Cunningham was sent to New South Wales to collect plants on John Oxley's 1817 expedition to the Lachlan and Macquarie Rivers. He was the botanist on Captain Phillip Parker King's survey of the Australian coasts from 1817 - 1820 and later made botanical collections in New South Wales, Queensland and New Zealand.

Although primarily a botanist, he was equally proficient as an explorer. In a series of expeditions he discovered Pandora's Pass through the Liverpool Range (1823), located the rich agricultural area of the Darling Downs (1827), a route to them from Moreton Bay through Cunningham's Gap (1828), and mapped the Brisbane River to its source (1829). He would have encountered Hoop Pines on many occasions during his travels in northern New South Wales and southern Queensland.

In 1831 Allan Cunningham returned to England where he arranged his botanical specimens in the Kew herbarium and prepared papers for publication. He came back to Australia in 1837 and for a short time was the Colonial Government Botanist in Sydney. His health failed after a visit to New Zealand and he died from tuberculosis in a cottage at Sydney Botanic Gardens on 27 June 1839.

Hoop Pine in the Australian National Botanic Gardens

Photo : John Turnbull

Cunningham's main collections are in Kew Herbarium but duplicates exist in many herbaria. Numerous taxa have been based on his collections and many of his manuscript names have since been taken up. His name is also commemorated in the genus Cunninghamia and in several Australian species including Acacia cunninghamii Hook, and Casuarina cunninghamiana Miq.

Hoop Pine is long-lived and can reach the impressive height of 60 metres and have a basal stem diameter up to two metres. Its narrow scale-like leaves are sharply pointed and slightly curved. They are arranged in spirals on branchlets and, like the well-known Norfolk Island Pine (A. heterophylla), the leaves and branchlets are shed as single units. The globular cones, up to 10 cm in diameter, develop at the ends of branches and break up on the tree when the seeds are mature.

This tree flourishes on well-drained, relatively fertile sites dominated by subtropical rainforest in coastal areas of northern New South Wales and Queensland. It is found on many islands off the Queensland coast and extends into Papua New Guinea and West Papua. Mature trees often emerge above the canopy of broadleaved rainforest species. In wetter areas its associates include Queensland Maples (Flindersia species), Rosewood (Dysoxylum species) and species in the Lauraceae family. On alluvial sites and near creeks it is associated commonly with Black Bean (Castanospermum australe) , Brown Pine (Podocarpus elatus) and Silky Oak (Grevillea robusta). On the driest sites, the Queensland Bottle Tree (Brachychiton rupestris) is an associate.

Hoop Pine is the most important native conifer for wood production Queensland. In addition to the natural forests there are about 40,000 hectares of Hoop Pine plantations, mainly in southeast Queensland. The white to pale brown wood is relatively free of knots. It is strong and easy to work, paint and stain. With these characteristics it makes excellent timber for internal beams and flooring, cabinet work, boat building and plywood products. The wood is also tasteless, odourless and very fine-grained and it is one of the few timers in the world that can be used with foodstuffs. For many years it was used for boxes in which butter was exported and today a Queensland company uses hoop pine to supply ice cream sticks globally !

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Welcome Stephen Speer

Stephen Speer has been appointed to the position of Program Manager, Communications and Visitor Services (formerly Public Programs) within the Gardens. Steve was formerly a member of the CSIRO's Discovery Centre team.

He started with the Gardens on 15 October. This is a key management position responsible for a range of important functions, including liaison with Friends and Guides. The Friends look forward to getting to know Steve and wish him success and fulfilment in his new position.

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  Boobook ...

     Mopoke ...

         Morepork ...

          

Tony Lawson

Since May this year, a Powerful Owl has caused great excitement for bird watchers by regularly returning to the same part of the Gardens. This is either the first or second record for urban Canberra. They are more usually found in the forests to the east (Tallaganda) or west (brindabellas) of Canberra. The Powerful Owl is Australia's largest owl.

At other times, we are much more likely to spot his smaller cousin, the Boobook Owl, Ninox novaeseelandiae. If the Gardens were open at night we would be more likely to hear rather than see the Boobook. In fact, it gets its name from an attempt to represent its call. Other names, such as 'Mopoke' and 'Morepork', are also attempts to represent the two-syllable call.

The bird in the photograph was seen beside the rainforest gully in the Gardens. If you look very carefully, there appears to be another owl behind and to the left. This is typical daytime behaviour by owls. They roost quietly where they hope that they won't be seen, particularly by other birds which would mob them. Sometimes dense vegetation is chosen or alternatively a tree hollow may be used.

Owls hunt at night, using their powerful claws to grab their prey, unlike other nocturnal hunters, such as the Tawny Frogmouth, which grabs prey with its large mouth. Owls have three special features to help them with their nightime hunting. They have very good eyesight to see in the dark, and very good hearing to find their prey. Thirdly, they have 'soft' features so that they can fly silently and not alert their prey before it is caught. The Boobook fees on insects, and small mammals, birds or lizards.

The Boobook is Australia's smallest owl. It is about half the height of the Powerful Owl and a quarter the weight. For some reason, Australia is not well endowed with owls - there are around nine species, of which five have been seen around Canberra. In other parts of the world, much smaller owl species are to be found. The Boobook is the most common owl and is found throughout Australia, as well as New Zealand and parts of Indonesia and Papua New Guinea.

The Boobook is the best studied Australian owl. Jerry Olsen and his team at the University of Canberra have been studying them for over a decade on the other side of Black Mountain to the Gardens. Unfortunately that area has been disturbed by the new road that is being constructed and some sites have been abandoned by the birds, due to the loss of roosting trees, next hollows or habitat for hunting. A lot has been learnt about their behaviour from these studies. For instance Mum takes on the main responsibility during the early stages of breeding but once the birds are fledged she takes off for a vacation and leaves the rest of the bringing-up to Dad.

The Boobook can be readily distinguished from other owls by its size and by its call. Otherwise, there are two broad groups of owls distinguished by their face masks. The eye discs of the Tyto family (Barn Owls) nearly meet on their forehead and they have dark eyes. The second group comprises Hawk Owls which have eye discs separated by a broad forehead and light eyes. The Boobook is a Hawk Owl. Its distinctly dark eye discs are surrounded by a pale border.

The photo was taken in the Gardens on 14 January 2007
by Rose Miller, a visitor on a guided walk
.
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Diseases in the garden and Gardens

Paul Janssens

Part One of this series, 'Managing bugs in your garden', was published in Newsletter No. 56 July 2007 (click here to view it in Archives). Diseases, for the purposes of this article, are pathogens such as smut, rust, fungal and viral organisms that can be found on plants.

Diseases are often constantly present within a garden environment. It is when favourable conditions aren't present that they remain in small populations and the plant can cope with the presence of the disease. It is usually when conditions favour the disease pathogen that the disease increases in number and size and this can have an effect on plant vigour and general health. It can also be when the conditions for pathogens are favourable, that these same conditions can cause plant stress. When plants are stressed they can be more susceptible to disease infection.

Diseases can be either soil borne or occur on the surface or within plant tissue.


Armillaria and remedial action in the Gardens

Photo by Heino Lepp

Phytopthera cinnamomi is a disease of plants that can be devastating to plant health, and occurs in the soil. It is a very mobile disease that can move through soil in soil water. If a garden has Phytopthera then it can be very hard to control. Foot dips are the best way to prevent the disease spreading as well as good water management. Run off and excessive watering of gardens can spread Phytopthera. A soil test would be required if Phytopthera is present. Plant symptoms include die back and usually plants growing together will be affected as the disease moves through soil. This isn't common in domestic gardens but is worthy of a mention as it has affected the Jarrah forests of Western Australia and is mentioned by visitors to the ANBG.

Armillaria melia is another soil borne fungus. It has been known to devastate many forested areas. It doesn't move through soil by free water and so isn't as mobile as Phytopthera. A related Armillaria (Armillaria luteobabalina) occurs at the ANBG and has killed many species growing in affected areas. It destroys plant roots in the cooler months and the plant can't survive increasing temperatures because it is unable to supply water due to a depleted root system. This isn't common in domestic situations and is mentioned due to its effect on certain sections at the ANBG. It occurs in the Acacia sections above the rockery, at the very top of the Eucalypt lawn and towards the new nursery, to name a few sections.

Leaf blights and spots can occur on some native species. Again, control of these can be difficult and unnecessary in many cases. Two commonly found fungal diseases are :

  • Sooty Mould. This is a secondary condition to scale attack on plants. The scale sucks sap from plant leaves and a residue called Honeydew forms when sap is found on the outer surface of the leaf. Ants love Honeydew and are often found on plants that have scale. The Sooty mould then grows on the Honeydew. The best way to control all of these is to control the scale with a pest oil. If sooty mould is all over a plant and detracts from the look of the garden, it is best to remove and replace that plant. Spraying sooty mould does not remove it.
  • Powdery Mildew . Powdery mildew can be found on young Eucalyptus seedlings when propagated. It occurs as white spots on the upper and lower surface of the leaf. It can be controlled by improving air circulation around the plant or spraying with Lime-Sulphur. It doesn't harm plants but can slow plant vigour.

Diseases may be seen in gardens but the main message from this article is that they are not easy to control; they occur due to plant stress and when conditions are favourable for the pathogen. There is no need to spray chemicals around your garden but rather accept that diseases are a part of the garden ecosystem. If infections are seriously harming plants or the aesthetics in your garden, then consider removal and replacement of badly affected plants.

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Growing Friends

The Growing Friends were very disappointed they had to cancel the spring plant sale, originally scheduled for 13 October. Hailstorm damage and other problems greatly reduced the stock available for sale. The Growing Friends hope for a very successful autumn sale in 2008.

Water Tank :

On 18 October the Growing Friends took delivery of a 9000 litre rainwater tank to help meet their future water needs. They had been concerned that, if more severe water restrictions were to be introduced in future, their plant propagation activities might become impossible. At their request, Friends Council agreed to provide up to $4,000 for the tank and pump

 

Photo : Barry Brown

 

New propagations :

The Growing Friends recently propagated cuttings of Calothamnus quadrifidus and Acacia covenyi  and hope that they will be available for sale in the autumn .

Calothamnus quadrifidus is in the Myrtaceae family and is found in south-west Western Australia. Commonly named 'net bush' because the long stamens on the one-sided flower clusters resemble a net. Spring and summer flower, and bird attracting, this plant grows best with some overhead cover.

Calothamnus : Greek kalos - beautiful; thamnus - shrub. Named by Robert Brown who collected three species when he visited Lucky Bay near Esperance, WA, during the Flinders expedition in January 1802. Quadrifidus : flower parts in fours. Brown thought this was an unusual character. He was not to know that most species in the genus also have this character.

Photo : Murray Fagg


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Acacia covenyi is in the Mimosaceae family from the southern tablelands of NSW. It can be a large shrub or a small tree to six metres. It has attractive blue/grey foliage and is commonly known as the Blue Bush. The phyllodes are broad-linear to 5 cm and with large bright yellow ball flowers which occur in spring - altogether a spectacular sight. It is hardy and frost resistant.

 

Acacia : Greek akakia was used for a thorny Egyptian tree (from akis, sharp point). Subsequently the genus was formally named Acacia

Covenyi : after R Coven, botanical collector at the Royal Botanic Gardens, Sydney.

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Friends' Briefs

Death of a dinosaur

The Wollemi Pine (affectionately known as "Wally" by some volunteer guides), which had apparently been growing well in its protective cage for the past seven years, has died. Paul Janssens, Curator, Living Collection at the Gardens, believes the drought is not to blame. Gardens' staff will remove the tree and have soil samples analysed. There is some concern that a soil pathogen may be responsible, and soil analysis will test that.

Paul says he is particularly sorry to lose this plant - although Wollemi Pines are now readily available commercially, the dead plant was much closer genetically to the natural stand of trees in Wollemi National Park than those now for sale.

However, all is not lost - other Wollemi Pines (uncaged) have been planted elsewhere in the Gardens and seem to be growing well. Whether one is relocated into the site by the Gymnosperm Loop depends on the outcome of soil testing.

Summer Concerts

Gardens' management has decided that the summer concert program in January 2008 will be significantly shorter than in previous years. The next season will run for only four concerts over two weekends : Saturday 12 / Sunday 13, and Saturday 19 / Sunday 20 January.

For the last few years, summer concerts have been held over five weekends, and before that throughout January and February. This decision is a disappointment to the Friends. It will greatly reduce our ability to raise funds to support the Gardens. The wider Canberra community, which has enthusiastically supported the summer concerts over many years, will surely be disappointed.

Friends Council urged management to retain the five-weekend season. Sadly, budgetary constraints and reduced staff numbers made that impossible. Council agreed to support the limited season this summer, in the hope that a more extensive program will be reinstated in 2009. We look forward to an enjoyable, if shorter, summer concert season.

As in the past, volunteers are needed for the concerts. Members who can help to collect donations from the audience (the 'bucket brigade') and staff the wine table are asked to leave a message on the Friends answering machine (6250 9548) or email : friendbg@netspeed.com.au. Please tell us which evening and which duties you are volunteering for and, if phoning, leave a phone number for us to get back to you.

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Compiled May, 2008 by Shirley McKeown   -  email : wombats1@tpg.com.au