'I like old things .... '

Alan Munns,
President of the Friends

... really old things. Geologically old. So my favourite part of the Botanic Gardens has to be the Gymnosperm Loop.

The flowering plants, the angiosperms, are recent arrivals on the evolutionary stage. They have been here for only a little more than 100 million years. But the gymnosperms - the conifers and cycads which mostly bear seeds in cone-like structures - have been here for much longer. They started to appear over 250 million years ago. For the following 150 million years or more, during the 'Age of the Dinosaurs', the world's dominant plants were conifers, cycads and ferns.

The Gymnosperm Loop contains a wonderful selection of Australian conifers and cycads. Plants from four conifer families occur in Australia and represetatives of each are here. There are podocarps, auracarias (including a Wollemi Pine, now bearing several male cones), callitris and a member of the sequoia family, the Taxodiaceae (Athrotaxis laxifolia from Tasmania, a close relative of both the King Billy and Pencil Pines).

And most stunning of all at the moment (early June 2007) is a cycad (Macrozamia communis, the Burrawang) with brilliant red fruit spilling onto the ground like red-hot coals tumbling out of a fire.

Photo : Alan Munns

"Watch your Friand!"

White-winged Choughs in the Gardens

The Late Tom Green

The White-winged Chough ('chuff') is a familiar bird to ANBG visitors. Choughs should fit well into the Canberra environment for they are the ultimate socialists. They are mid-sized dull black birds with a down-curved bill and a big white panel in each wing. This white patch is only visible when the wings are extended in flight or threat display. They live in extended family co-operatives.

Photoshopped by Rawson

Photo : Geoffrey Debb

While walking in the ANBG you will often come across a flock of Choughs busily searching through the leaf litter and garden mulch for the spiders and insects that make up most of their diet. Food is shared among the group, apportioned according to need. Sharing food helps strengthen group bonds. The cafe is an easy source of food for the Choughs which swoop on any unguarded food items. While you protect your small tart from their depredations you may seea unique response from the Chough - they are able to force blood into both eyes and the surrounding membranes.

The resulting big blood-red eye is both an expression of anger and an attempt to dominate you. Please don't be bluffed into sharing your food, they have become quite a nuisance around the cafe.

Choughs seem to have adapted to the Canberra urban fringe and are increasing in numbers. They do need to retreat into nearby bushland to breed and several groups breed in the ANBG.

The group combines to construct a big nest out of mud, building it up in coils like the clay pots we made as children. A mud nest only works well in dry country and Choughs are uncommon in the humid country east of the Great Dividing range. When it rain some poor team member has to perch over the nest, with wings extended, to divert the raindrops. Conversely if mud is in short supply they may use fresh cow manure instead! More than one female may lay in the next and the whole family helps to feed the nestlings and protect them from passing Currawongs.

Sharing a nest works out for the Choughs. Several studies have shown that larger groups bring more food to the nestlings which grow faster as a result. Groups of Choughs are better able to protect the next and fledglings than pairs nesting alone, so more chicks survive to join the flock.

Choughs have a reputation for being a bit dim but they can see the advantages of belonging to a large group and trying to recruit passersby into their family. If they meet a fledgling from another group they will offer it food and grooming in the hope that it will join them. Often this 'kidnapping' works and the confused youngster will wander off with its new family.

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Wondering About Feather Lice

Ian Fraser

A very short extract from Ian's talk to the Friends on 19 April 2007 entitled
'At least 25 things to wonder about in autumn'

'As a complete generalist, I'm fascinated by extreme specialisation. How about species of feather lice which not only specialise in a single bird species, but in different parts of the bird's body? A bird may have up to a dozen species of feather lice, all limited to that one bird species and never coming in contact with each other.'

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When is a native species a weed ?

Geoff Butler

The ACT Weed Strategy considers a weed '...to be a terrestrial or aquatic species of native or non-native plant that is harmful to the natural environment, agriculture, and other industries, and public amenity and health.' In recent years there has been a stronger emphasis on native plants as weeds. So when does a 'native' plant become a weed ?

OVERSEAS

There are a multitude of Australian species that have been introduced to other countries around the word as ornamentals or for a particular function. They have proven so adaptable to their new surrounds that they have naturalised. The intensity of infestations varies, but a not inconsiderable number have become significant weeds that are difficult to manage. South Africa, Central American countries, New Zealand and Mediterranean countries in particular have many Australian species aa weeds. Australian species that naturalise in this way are surely weeds, growing well outside of their original natural distribution.

Weeds overseas : Left : Paraserianthes lophantha (M.Fagg)        Below :Grevillea robusta     (C.Green)

WITHIN AUSTRALIA

A similar situation exists in many parts of Australia. Some 'native' species have been introduced to other parts of the country, particularly as ornamentals, and they have managed to establish themselves. The best known and publicised example locally is probably Cootamundra Wattle (Acacia baileyana).

However, it is of some concern that many species within their natural ranges are being labelled as 'woody' weeds. This is particularly so on the western slopes and rangelands. There are a number of species in these areas that are unpalatable to stock. As they are not eaten, and everything else is, they can rapidly multiply and fill overgrazed bare spaces. Other land management actions may also affect some of these species, for example, fire and fire frequency, but as they grow they compete heavily with species preferred by stock and can develop into almost monocultures. Probably the best know examples are Desert Fuschia (Eremophila gilesii), False Sandalwood (E. mitchellii) and Turpentine (E. sturtii).

There are some innovative people, however, who are examining other uses for some of these Eremophila species, for example, fuels and oils. If these prove feasible, farming production could diversify and become a more sustainable activity, if the grazing of such marginal lands is to continue.

These species, along with various Senna species (S. artemisioides, S. nemophila, S. eremophila), Hopbushes (Dodonaea viscosa subsp. angustissima, D. attenuata), Mulga (Acacia aneura) and White Cypress Pine (Callitris glaucophylla) are actually 'thickening' stands of vegetation by their 'infestations'.

As the landuse is currently grazing, they are a 'weed' in the sense of most definitions of weeds, but concerns are held about their current weed status. They are the result of particular land management activities, and they are being provided with the opportunity to recruit new generations. If these lands continue to be used beyond their carrying capacity, these 'woody weeds' will continue to escalate. In some places that have been severely cleared of native vegetation, these indigenous species are often all that is left on the overgrazed roadsides. It would be outrageous if these last reserves of indigenous vegetation were targeted as woody weeds. In cases such as this I take issue with the fact that they are weds, as better land management and uses would probably eliminate the 'problem'.

LOCALLY

There are some local species that are regarded by some as woody weeds. Examples are Purple Kunzea (K. parvifolia), Burgan (K. ericoides) and Silver Wattle (Acacia dealbata). Once again, they are indigenous species doing what they have evolved to do. We are seeing, in the smallest blip in time, the early successive regeneration of landscapes by these species. While recognising there are land uses where these species are less desirable, the answer is not to just knock them down or burn them, as this disturbance is what they best respond to. I again take issue with them being weeds in the local area.

Local Weeds   From top left : Kunzea parvifolia (G. Manley), Kunzea ambigua (A. Lyne), Callistemon subulatus (S. Douglas), Sollya heterophylla (M. Fagg), Grevillea rosmarinifolia (A. Lyne), Acacia pravissima (unknown), Crowea exalata (W. Molyneux)

However, there are some introduced native species that we need to recognise are spreading in the local region. Examples of these are the Cootamundra Wattle mentioned earlier, Snowy River Wattle A9A. boormannii), Ovens Wattle (A. Pravissim), Rosemary Grevillea (Grevillea rosmarinifolia) and grevillea hybrids (mainly from G. victoria, G. juniperina, G. rosmarinfolia and G. lanigera).

Some other species being monitored locally are Coast Wattle (A. sophorae), Blue Gum (all those species generally referred to as such), WA Bluebell Creeper (Sollya heterophylla), Waxflower (Crowea exalata and hybrids), Calistemon subulatus, Correa reflexa, Philotheca myoporoides, Coast Tea-tree (Leptospermum laevigatum) and Tick Bush (Kunzea ambigua). Some of these species are throwing occasional seedlings, especially in garden situations, but this does not necessarily mean they should be immediately removed as weeds. they should be monitored, and if the escapes continue to grow, there may be a need to review their status.

FINALLY

A word of caution about weed publications which include native species. Sometimes these publications try to deal with too many categories of weeds under one cover. Some of these publications have Blue Devil (Eryngium rostatum) or Native Violets (Viola hederacea) clearly illustrated and readers presume they are weed species without checking the text for the context in which they may be weeds. In the case of Blue Devil it looks thistle-like and is sometimes illustrated with the explanation it is not a weed, and violets are said to be found in turf in moist areas - big deal! So be careful before assuming that those native species which you have growing, and which are illustrated in that new weed book, are actually weeds!

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Managing bugs in your garden

 Paul Janssens 

Pests are commonly described in horticulture as insects that eat or damage plants. Pests can also refer to all pathogenic organisms that affect plants including diseases (rusts, smuts, pythium and armillaria). Pesticides as a consequence refer to a chemical or substance that controls all pest organisms including diseases and insects. This is an abridged article on insect pests; the complete article is on the website. An article on diseases will appear in a later newsletter.

For many years we assumed that all insects were bad and we sprayed our gardens to kill them all. in the past 20 years there has been a significant shift towards treating them on a case by case basis. This is known as Integrated Pest Management (IPM) and is managing pests with cultural, biological or chemical means. you can manage the insects in your garden by using IPM.

The first thing you must know is what sort of pest it is. If you are unsure, you can ask at the Australian national Botanic Gardens or your local nursery. And remember, some insects in our gardens are beneficial and actually feed on the bad pests.

The Goodies

Green Lace Wings - as the name suggests they are green and have clear wings. Females lay up to 600 eggs in clusters on a small stalk to protect them from ants. The larvae feed on aphids, mites, mealy bugs and white fly.

Lady Birds - lay their eggs in the egg mass of common pest insects like mealy bug. When the eggs hatch, the larvae immediately begin feeding on the host eggs.

Some Baddies - Sap Suckers

Scale - there are several species varying from a small round dome to clusters of 'cocoons', protected by a crusty surface. If the population is low and the plants aren't stressed, leave them; if it is high, apply a pest oil, e.g white oil, to coat the leaf surface and suffocate the scale.

Psyllids (Lerps) - small insects with sugary crusty coating for protection. Can have an impact on eucalypts if in large populations. Control can be difficult when in upper branches. If numbers are low, don't worry but monitor. If spraying is required use a pest oil to 'smother' them.

Spittle bug - nymphs attach to leaves using mouthparts and suck, producing foamy liquid 'spittle', formed by air being taken into abdominal channel and expelled through anus, forming bubbles. Bugs are rounded, slightly dome-shaped, 10mm long. Nymphs resemble adults but lack wings. Control not necessary if in low numbers. If damage is seen, then spray with a pest oil or Confidor*.

Aphids - small pear shaped, green insects; can occur in large populations. Have wide range of hosts, exotics and many natives, e.g Chrysocephalum apiculatum, orchids such as Thelychiton and grevilleas. Best not to spray if in small numbers as they are food for the Goodies. If damage (leave discolouration) is occurring, control with a pest oil, soapy water, some soap insecticides or Confidor*.

Mealy bug - found above and below ground so can attach roots of indoor plants without being seen. Are small, 'woolly' and white and move slowly on leaves and branches, but if numbers are high they look like a mass of white fluffy material. If populations are low they are food for ladybird lavae. If numbers are high, control first with pest oil,then an insecticide, Confidor* or Folimat**.

More Baddies - Leaf Eaters

Cup Moth - named after cocoon like structure it pupates in. Adults are small moths, 4 cm long. Lay eggs in clusters on eucalypt, melaleuca, guava and apricot leaves. When hatched many larvae feed on the same leaf; as they mature, they get a leaf each. Have retractable spines as a defense, which sting if touched. Best control : remove with gloved hand and squash with a sturdy foot.

Processionary Caterpillars - small hairy caterpillars that move in a line along branches or leaves. Hairs can irritate if touched. The affect eucalypts and some Acacia species. Some species bind leaves together to form a 'nest', which they eventually eat; can then defoliate whole trees. If numbers are low, best control is to remove them with a gloved hand and squash with a sturdy foot.

Steel Blue Sawfly Larvae - 'spitfires', as they spit a substance that irritates open wounds and/or eyes. The larvae do the damage; can defoliate entire eucalypt trees in several weeks. Best control : knock them from the tree (if within reach) and squash them with a sturdy foot.

Christmas Beetles - largish beetle, about 20mm long, present in large numbers in summer. Adults feed on eucalypt leaves; can cause severe defoliation if lots of them. The larvae develop in the soil, eating decaying organic matter or plant roots, causing plants to wither and turn yellow. Adults emerge in spring and fly to the nearest food plant to feed and mate.

 

*    Confidor is a pesticide that is purchased as an aerosol. It is convenient as no mixing is required
      but protective equipment (gloves, mask, overalls) must be worn.

**  Folimat is an aerosol pesticide, easy to spray on small infected areas but protective equipment
     (gloves, mask, overalls) must be worn.

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Returning Some Balance -

tackling Indian Mynas

Bill Handke
President, Canberra Indian Myna Action Group Inc.

A delight in living in Canberra is the close connection we can have with our natural environment, our native plants and our wildlife. As Friends of the Botanic Gardens well appreciate, the link between people and our native plants and animals is brought together particularly well in the Australian National Botanic Gardens. Many of us will seek to replicate this in our own gardens, using native plants that bring in honeyeaters, wrens, parrots, etc. But our natural environment and our gardens are at a serious risk from an introduced bird, the Indian Myna (or Common Myna). These birds are both a serious threat to our wildlife and a major nuisance in people's backyards, around schools and shopping centres. By taking over nesting hollows and preying on eggs, chicks and young they are a threat to our native rosellas, kookaburras, etc. and small mammals like sugar gliders.

Indian Mynas have been voted the most hated pest in Australia, beating cane toads, feral cats and foxes ABC Wild Watch Quest for Pests, 2005

Many people are also greatly disturbed by the way they scare native birds away from their gardens and foul their patios and barbecue areas. Schools and shopping centres have very high numbers of these pests, while mynas around cafes can be a health risk.

The Indian-Myna-matter in Canberra has taken a positive turn with over 10,300 Indian Mynas removed from around Canberra and Queanbeyan over the past year by 230 backyard trappers. The trappers, members of the community-action group, Canberra Indian Myna Action Group Inc (CIMAG), have made a huge difference. There are now regular reports that myna numbers have dropped significantly in local areas, native birds are coming back into backyards and, last breeding season, rosellas returned to nesting hollows.

Kambah has been a particularly successful area for trapping. With 22 people with traps, 3061 mynas have been removed from Kambah over the past year. Other highly successful suburbs are Garran, Duffy, Pearce, Theodore, Aranda and Hall.

This is wonderful news for our native wildlife. And some considerable respite for people who are concerned about the presence of mynas in their backyards.

But the job has a long way to go. Indian Mynas continue to be seen in big numbers in many parts of Canberra; around shopping centres and in areas where there has been little or no trapping. Gungahlin marketplace is a major roosting site with some thousands of mynas roosting communally at night and fouling the area.

More needs to be done to reduce the opportunities mynas have for feeding, breeding and roosting. All Canberrans can help in this work:

• by not feeding the birds directly or indirectly - don't leave cat or dog food out during
  the day
  
  
• by blocking holes in roofs and eaves and other areas around the house - mynas can use these as nesting hollows
  
  
• by removing pencil pines and similar dense-foliage exotic trees that are used as roost trees at night.

The trap CIMAG members use is quite compact and readily made from our blueprints. We also hold workshops where people can make the traps under our guidance, and we make traps for members at a cost. Alternatively, people can buy commercial traps that are very effective.

If you want to know more about traps or the activities of CIMAG, contact
Bill Handke, the President of CIMAG (phone 6231 7461 or email handke@grapevine.net.au) or go to the website: www.indianmynaaction.org.au

You can have native birds or Indian Mynas - but not both
Ian Fraser, local naturalist and 2006 Winner Australian Natural History Medallion

Happy Birthday, Linnaeus '

Annette Wilson
Australian Biological Resources Study

May 23 this year marks the 300th anniversary of the birth of Swedish botanist Carl Linnaeus, 'Father of Taxonomy'.

Linnaeus pioneered the binomial system of naming living organisms that we still use today, laying the foundations for the systematic study and classification of plants and animals which we call taxonomy. However, he was more famous in his lifetime for his artificial 'sexual' system for the ordering and classification of plants.

Linnaeus was the eldest child of a rural clergyman. He was destined by his parents to become a clergyman, but he was not academic and his school-work was mediocre. He had a passion for plants from his earliest years, and at nineteen he began studying for a career in medicine, which in those days included botanical studies.

He studied first at Lund, then Uppsala where in 1729 he wrote a short paper that described for the first time his sexual system of classifying plants. He was appointed to give botanical demonstrations in the university's garden. The classes were packed, an indication of his charisma, the passionate interest he brought to his subject, or the titillating nature of his sexual classification system.

The theory that plants reproduce sexually was first published by Sebastian Vaillant in 1718. However, Linnaeus recognised that counting the sexual organs of plants provided an easy way to group them in an artificial but useful classification, which could be applied by both professional and amateur botanists. Using this method, anyone could categorise a new species, or easily locate information on a previously described one.

Plants were divided into Orders, which were based on the number and arrangement of male organs (anthers), with subordinate Classes based on female organs (pistils). As an example, a species with four anthers and two pistils in an hermphrodite flower was classified as Order Tetrandria (four males), Class Digynia (two females). Ascribing sexual characters to plants was considered risque, especially as Linnaeus called the anthers 'husbands', the pistils 'wives' and the flower the 'marriage bed'.

In 1753 Linnaeus travelled to Holland, and briefly to England and France, before returning to Sweden in 1738. He visited many scholars and scientists and made valuable connections as well as publishing several important works. These included the first editions of Systema Naturae, in which he described his system for the classification of the three Kingdoms of Nature (plants, animals and minerals), and Genera Plantarum.

All his botanical publications employed the sexual system of classification, which was becoming more widely known and vigorously debated. Some writers condemned it for its lewdness, while others admired its utility and yet others deplored its artificial grouping of plants recognised to be only distantly related.

After returning to Sweden Linnaeus took up medical practice to make ends meet. However, matters improved: he made connections at the Swedish Court; married his long-term fiancee Sara Lisa; his son Carl (known to botanists as Linnaeus filius) was born in 1740; and he was appointed professor of medicine and botany at Uppsala University where he remained for the rest of his life.

As he settled into Uppsala his reputation and inspiring teaching brought him students, his 'apostles'. The best-known of these, to Australians at least, was Daniel Solander, who travelled with Cook and Banks and made the first major collection of Australian plants in 1770.

Linnaeus wrote prolifically, but it was the publication in 1753 of Species Plantarum which immortalised him in botany. It was the first catalogue and description of the world's flora, containing nearly 6000 species. The consistent use of a two-part name (genus and species) was quickly adopted by other botanists, and we still use it today. Species Plantarum is now internationally accepted as the starting point for botanical nomenclature; names published before that date have no official standing.

His collections and papers, kept by his son until the latter's premature death in 1783, were eventually sold to J.E. Smith in London. There they became the pride of the Linnean Society of London, and today are kept in a specially designed room at the Society's headquarters.

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Growing Friends

Pauline Wicksteed and Loris Howes

Since 1993, the propagation wing of the Friends has been giving members the opportunity to enjoy hands-on growing. Early meetings were held in the cottage at the top of the Gardens; now they are held each month at the Banks building where matters of interest are discussed, before one or two selected members give a presentation describing specific plants which they have provided for the day's propagation.

All cuttings must be sourced from within the Gardens to prevent contamination, and approval has also to be obtained from the Gardens well in advance, as many plants are not available for various reasons such asinterstate agreements, protection of rare species, and cultivars covered by plant variety rights legislation. Seeds are obtained from authorized seed suppliers, as well as the Gardens.

The Growing Friends have their own space within the Gardens, including a plastic igloo containing a hot bed for cuttings as well as work space, a large shade cloth covered area that houses our potted plants, and a watering system. This area was damaged by the hail storm of 28 February and plants were smashed. Fortunately, this did not unduly affect our plant sale a month later.

Plant sales are held in the Gardens twice a year, in spring and autumn, and the recent sale was our most financially successful to date. We hope it was also successful for those who bought and planted some of the wonderful variety of plants we had to offer.

Two plants recently propagated by Growing Friends:

Schoenia filifolia in the Asteraceae family, was propagated from seed, but it can also be grown from cuttings. It is a compact, branching annual to about 40 cm high with linear leaves about 10 cm long. Flower heads are 4 cm wide, occur singly on the end of stems, and are lemon-yellow with papery bracts around a yellow centre. It prefers well drained soil in a sunny position and makes a very colourful display, expecially in massed plantings.

Photo courtesy Nindethana Seed Service

Photo : Murray Fagg

Platysace lanceolata in the Apiaceae family, was propagated from cuttings from the Sydney Basin area of the Gardens. It is a small woody shrub usually about 1 m high to 1 m wide, with white or creamy flowers in dense compound umbels, flowering in summer. Leaves vary from round to lance-shaped. It is a hardy plant, distributed throughout Queensland, New South Wales, ACT and Victoria, growing on sandy soil in woodland and heath.

 

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Friends' Briefs

Rock Garden Shelter
	The official opening on 29 March of the attractive new Rock Garden Shelter, by Her Excellency Mrs Marlena Jeffery, was a happy occasion. The shelter, designed by Tony Trobe, winner of the 2007 Master Builders House of the Year Award, is the first project to be financed by the Friends Public Fund. Photos : Murray Fagg

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