Thursday, 30 September 2010

Precipitous pea*

This rare species of pea has just (17 September 2010) been given what is called a 'preliminary determination' as a Critically Endangered Species in New South Wales. The NSW Scientific Committee will now seek and consider public submissions before making their final determination on  Pultenaea sp. 'Genowlan Point'.

In the latest survey by Jan Allen, in May this year, there were 15 plants, only two more than the worrrying low of 13 four years ago. This is what I said about it in 2006, on the Weekend Show with Simon Marnie (702AM): 

The Wollemi Pine is perhaps our best know ‘very rare’ plant, but more than a thousand plant species are threatened with extinction in Australia.

Not all threatened species are as charismatic as the Wollemi Pine. The Nightcap Oak (Eidothea hardeniana), a member of the generally charismatic protea family, is know from only 23 individual plants on the Nightcap Range in northern NSW.

The Nightcap Oak is being propagated at the botanic gardens, but its tiny white flowers won’t compete with the showy waratah or banksia.

A plant on the brink literally has been nicknamed – by definition rare plants are rarely common enough to be given ‘common names’ – Precipitous Pea. This species of Pultenaea was discovered nine years ago but is yet to be given a formal scientific name.

The Precipitous Pea is a small nondescript shrub, only attracting attention when in flower.

Although it sounds like the name of a jazz band, the nickname is particular apt. This plant clings precariously – physically and for its long term survival – to the edge of a cliff above Capertree Valley, just north of Lithgow. Drought and browsing by feral goats has meant that the 64 individuals discovered in 1997 have now been reduced to 13.

A few weeks ago, volunteers joined staff from the Botanic Gardens Trust (at Mount Tomah Botanic Garden) and the National Parks & Wildlife Service to give the remaining plants some much needed TLC.

Tree guards were erected and the plants were watered with chlorine-free water. The team were careful to wash their boots and equipment to make sure no pests or diseases were brought into the site.

Locals are helping not only by volunteering, but by keeping clear of the area at all other times to help protect the plants from trampling and disease. If you want to see the Precipitous Pea, its best to visit the Mount Tomah Botanic Garden where we have a single plant on display in our, unprecipitous, Rock Garden.

*From the Archive (spoken but not wroten). Images by Simon Nalley, posted on the 2005 Department of Environment, Climate Change and Water plant profile for this species.

Tuesday, 28 September 2010

Fungus Fart

This charming little story comes care of friend and colleague Jim Croft, who is always on the look out for botanical novelty and novel botanicalty.

I wasn't sure whether to use Jim's original title, Fungi Farts, or the more adjectival Fungal Farts. In the end I went with the more classical approach, borrowing from Titus Groan.

The story comes from the latest edition of the Proceedings of the National Academy of Science, via New Scientist, via Jim.

But enough of the prelude. It seems that some fungi fart, or more politely, 'produce wind'.

They do this to spread their spores further, so they can find new hosts to bother or debri to compost. In general they use the wind, just like many flowering plants do when they produce winged and feathery seeds. But as New Scientist point out, sometimes there just isn't a good breeze.

Researchers at the University of California, in Berkeley, lead by Marcus Roper, have been studying what I used to call ascomycetes. Goodness knows whether they are still called this but all ascomycetes produce spores in little sacks called 'asci' - hence the name.

These asci-producing fungi have a range of vessels for holding and releasing these spore sacks, and about 8,000 of them produce what are called 'apothecia'. These apothecia are cup-shaped structures lined with asci. So there you go. That's pretty much what I remember along with what New Scientist provides as background.

The problem for any fungus is that its spores are small, extremely small. If they were to be ejected one-by-one they might only travel a few millimetres and it would be a pretty energy intensive process to fire of each ascus.

Instead it seems that some species, and maybe all, use a shot of air to fire off all their spores.

Roper and his team have been filming the spore ejections, as they call them, from fungus called Sclerotinia slerotiorum, which causes White Mold and other nasty rashes and diseases in a range of crop plants.

What they found was by ejecting thousands of spores at the one time (from their asci in the apothecia...) a small jet of air resulted in the spores travelling 10 centimetres rather than 3 millimetres if a single asci releases alone.

It's thought a drop in air pressure triggers this syncronised release, starting with a few 'pioneer spores' and then leading to changes in the apothecia tissue causing the mass ejection.
While it's fun to use this research as an excuse to head a posting with Fungus Farts, something like $1 billion is spent each year in the US to protect crops like tomotoes and sunflowers from Sclerotinia slerotiorum. Marcus Roper tells New Scientist that understanding disperal better may lead to vastly improved control of this troublesome pathogen.

Image: What I hope is an ascomycete, beside Roses Gap Road in the Grampians, in Victoria, about this time last year. I know it looks a lot like a chocolote confectionary of some kind, but it certainly isn't that.

Monday, 27 September 2010

Here Today...Flowers that Change*

One more from the archive. By the way, the rose mentioned at the end is in spectacular flower at the moment. But in 2006:

Violet yesterday, blue today, white tomorrow… That’s a Brunfelsia flower – well more or less. The flowers may take a few days to change colour, but that hasn’t stopped this Brazilian shrub being given the rather explanatory common name ‘Yesterday Today and Tomorrow’.

These brunfelsias are sometimes also called ‘Kiss Me Quick’, presumably a reference to the fleeting colouration of the flowers.

The commonly grown shrub around Sydney is probably Brunfelsia bonodora - there is some confusion over the names used. It’s an easy to care for garden plant, but just watch the pods which are poisonous to dogs and seem to be attractive to them.

YT&T, as it might be tweeted, is not the only plant with transforming flowers. Most aspects of the flower are related in the way the plant reproduces, and colour is usually linked to the method of pollination.

The best know example of this is the Victoria Lily, Victoria amazonica or V. cruziana, from South America. The flowers emerge white from below the water each night. The first night the flower attracts insects, trapping them within the flower when it submerges in the morning.

The second night the flower is flushed pink, an unappealing colour to insects and the bedraggled bugs fly away to pollinate another (white) flower. So far we’ve had only produced small-leaved plants in the botanic gardens ponds, but when fully mature the leaves can famously support a small child.

And there is a lovely China rose, Rosa chinensis ‘Mutabilis’, whose species name is Latin for changeable. And change it does, from pale yellow to red. You can see it doing its thing in the garden opposite the Robbie Burns Statue, in the Domain on the way to the Art Gallery from St Mary’s. (By the way, this is a rose that’s easy to grow in Sydney – it needs little spraying or dead heading, and its limp branches are difficult for possums to climb…)

Of course even plants with flowers that don’t change colour will be different yesterday, today and tomorrow. That a pretty much sums up a garden – something new to see every day.

A less common species of Brunfelsia, Brunfelsia pauciflora, in the Royal Botanic Gardens

*From the Archive

Saturday, 25 September 2010

Waratahs, and this time they're red, pink and white

My last posting was all about Blue Waratahs and some creative use of Burton Blues low sheen acrylic. This time the blooms were all natural, albeit with a little creative breeding.

I've been up the mountains, at Mount Tomah Botanic Garden, helping to open the Wild about Waratahs Festival for 2010.

The Festival runs from today until 10 October and includes a whole bunch of waratah related activities. Today we featured Waratah Passion, and exhibition of works by Jenny Kee, including (amongst some portraits of waratah flowers) a 1.4 metre silk scarf featuring a collage of 24 of Jenny's favorite pieces.

This is Lynda (Entwisle) rather than Jenny peaking out from behind the scarf, but Jenny and her grandchild were both draped in one of these scarfs. Jenny told us red was her trademark colour, and the waratah her 'totem'. She is keen to have something she calls 'Waratah Park', a garden or planting in and around Mount Tomah Botanic Garden celebrating this indigenous spectacular plant.

The Waratah Bloom Competition winners were announced, with Craig Scott of East Coast Wildflowers scooping the pool for another year, including the top prize for Champion Bloom. Community Education Officer Rusty Worsman launched the Waratah School Art project, which include the painting featured at the start of this posting.

Outside the hybrid waratahs were in bloom and our photographer Simone Cottrell was gathering together staff (Rusty Worsman on right), children and pixies for the seasonal pictures.

Down the hill, the bulbs were doing their best, and doing quite nicely, to match the splendor of the waratahs...

Friday, 24 September 2010

Flossy silk pillows*

My wife Lynda bought a kapok pillow recently, persuaded by the claims of comfort, health and sustainability in production. The kapok is a rain forest tree from Tropical America, and the pillow is stuffed with fluff from its fruits.

Botanically the tree is called Ceiba pentandra. Ceiba is also the name now given to the Floss Silk Tree, a distinctive tree in the botanic gardens. It has a spiny trunk, pink flowers and then fruits that open up to release…fluff.

The Floss Silk Tree used to be called Chorisia speciosa but recent taxonomic research has meant it’s been combined into the now expanded genus Ceiba. So we now call it Ceiba speciosa. Or you can still use Floss Silk Tree. (Confusingly there is an Australian tropical tree called the Kapok or Cotton Tree – Cochlospermum fraseri – which also produces fruit fluff, but is unrelated to the Floss Silk Tree.)

Ceiba is in the plant family Malvaceae, which also includes the baobab or boab trees of Africa and the Kimberly (as well as hibiscus). The flowers of many species are bat pollinated, probably by smaller bats than the flying foxes roosting in the Royal Botanic Gardens.

The fluff-producing fruits are characteristic of Ceiba. The seeds are embedded, but not attached, to the fluff which spreads through the forest, or botanic garden. Each fluff fibre is a few centremetres long and covered in wax, making them water repellent and presumably good pillow stuffing material.

In the middle of the last century, life jackets and car seats were almost always stuffed with kapok fluff. Nowadays other materials are used and there is little commercial harvesting of kapok, but a small niche market exists.

The advertising spiel says a kapok pillow is resistant to mites, mould and mildew. The fluff, it is said, will never absorb any moisture.

Apparently the fruits are harvested sustainably. The kapok has always has a special significance in its native habitat. The Maya of Central America held that a giant Ceiba tree stood at the centre of the earth, connecting our world to the spirit-world above - very 'Avatar'... Even today, the kapok is often left when other trees around it were felled.

We don’t have the kapok growing the Botanic Gardens, but we do have at least two species of Ceiba, including of course the grand Floss Silk Tree. You can see a couple of the Floss Silks at the western edge of the Palm Grove – the biggest is just over 50 years old.

Image: Fluffy seed pods on a Floss Silk Tree in Sydney’s Royal Botanic Gardens.

*This Passion for Plants posting will also appear on the ABC Sydney website (under 'Weekends' or search 'gardening'), and is the gist of my 702AM radio interview with Simon Marnie on Saturday morning, between 9-10 am.

Tuesday, 21 September 2010

From the Archive: Golden Surprise*

This species has been flowering for the last few weeks in my neighbourhood. In 2006 it flowered later, after the Wisteria. This is how I described it then.

There’s this wonderful wisteria wrapped around a now dead eucalypt near my home. A couple of weeks ago, the wisteria’s purple haze was interrupted by a succession of massive golden coloured flowers.

‘Cup of Gold’ had joined the wisteria. It doesn’t take long for this rampant climber to take over a fence, or unsuspecting tree. The leaves are thick and shiny, soaking up the Sydney sun.

The flowers are spectacular. They are great big trumpets, about 15 cm across the mouth, with dark purple stripes along each of the yellow segments. They look very exotic, and indeed they are.

The Cup of Gold is one of eight species of Chalice Vine native to the tropical forests of central America. Chalice Vine, or Solandra, belongs to the notorious plant family Solanaceae, along with Deadly Nightshade, Mandrake and Datura (called Angel’s or Devil’s Trumpet, depending on your perspective).

It’s probably no surprise that its flowers and leaves contain some nasty toxins, a fact not lost to the Aztecs who used them as an hallucinogen. But edible plants, such as tomatoes and potatoes, are also members of this unsettling plant family.

Like many plants around Sydney, Cups of Gold are flowering their heads off this year. In a wet year, or if well watered, this plant will divert its energies into leaves rather than blooms. Drought often brings out the best floral displays – just look out for this year’s Jacarandas in a few weeks.

Plants tend to respond to tough conditions by producing more flowers, and potentially more fruits and seeds, and therefore more chance of surviving. Quite sensible really. The only problem with Cup of Gold, or Solandra maxima, might be that it can sometimes survive too well and it could smother native vegetation at the edge of bushland reserves.

Image: Cup of Gold in bloom, October 2006

Sunday, 19 September 2010

From the Archive: Nuts to You*

After making an obscure reference the other day to 'Nuts to You', my first Passion for Plants (P4P) chat with Simon Marnie in October 2006, I realised there is a batch of strories sitting on my computer but not blogged.

Back in their day these notes were posted on the ABC Sydney Radio pages but haven't survived the ravages of internet time and the remakes of this site. (My earlier chats with Angela Catterns - from 2002-2006 - are still available on the Botanic Gardens Trust pages. You'll notice the occasional borrowing/recycling from these in later posts...)

So...I thought I'd post a few of these from time to time. They still seem interesting, I think, and it means I can send people a URL if they become interested in one of the topics covered. Of course it also means I can post them I'm bereft of new ideas!

But enough preamble, to Nuts to You, or as I termed it yesterday, the Testicle Tree...
You may never look at the low hanging fruit of an avocado tree in the same way again.

I was intrigued to read in the weekly science magazine, New Scientist, that the name ‘avocado’ has an odd anthropomorphic origin. It seems the Aztecs knew the small-fruited ancestors of our commercial avocado well, and called this tree with golf-ball sized fruits, ahuacacuauhiti.

This loosely translates to ‘the testicle tree’. Apparently the fruits were not only smaller but more pendent that those of modern avocado trees.

The Spanish conquistadors had some trouble remembering this name. By 1699, when the British botanist Sir Hans Sloan provided the first English description, ahuacacuauhiti had contracted to avocado.

While this may now be worth a quiet chuckle, when the etymology was revealed to 18th century Europeans it caused quite a stir. The avocado’s suggestive shape and name led to it being banned from monastery gardens.

There are plenty of other plants named after body parts, often based on their supposed health-giving powers. Liverwort, nipplewort and lungwort got their name from the Doctrine of Signatures (or Signs), where plants were used to treat illness of the body part they most resembled.

Even after a plant had been more mundanely named, links were made for medical purposes. Sometimes you have to use your imagination to see the resemblance. An odd example cited by New Scientist is the pomegranate, which means ‘seeded apple’. It was considered good for toothache because when the fruit’s peel is stripped way, the seeds and pith were thought to resemble rows of teeth between the parted lips.

If you want to read more about the origin of the name avocado, or the Doctrine of Signatures, see New Scientist 9 September 2006 and 7 October 2006 respectively. By the way, botanists refer to the avocado by its very tasteful scientific name, Persea americana.

Image: A pair of avocados borrowed from

Friday, 17 September 2010

Rare Plant Survives Black Saturday

"@kewgardens #PlantOfTheDay Find out about shining nematolepis and how it became close to extinction"

That's the promise of a tweet sent by Royal Botanic Gardens Kew this morning, a promise fulfilled by visiting the Plants & Fungi pages of It's a good news story from last spring but why not revisit it as we celebrate spring in 2010?

I was curious about this story because the plant wasn't from the UK. It's all about a rare species from Victoria, Australia, described in the genus Phebalium by two of my old friends from the Royal Botanic Gardens Melbourne - Neville Walsh and David Albrecht - then moved to a new genus, Nematolepis, by the person they named the species after, Western Australian botanist Paul Wilson.

It's now called Nematolepis wilsonii.

When 'we' published the Flora of Victoria in 1999 (Neville and I were editors, but Marco Duretto wrote the account of this plant's family Rutaceae), the species was known from a single population of some 200 individuals near Marysville.

As most readers will know, the fierce fires that ripped through Victoria ten years later (February 2009)destroyed most of the town of Marysville and burnt and blackened much of the surrounding vegetation.

As reported on Kew's website, more than 4,500 square kilometres of land was burnt, more than 2,000 homes were destroyed and 173 people lost their lives. The entire population of Shining Nematolepis, as Kew calls it, was wiped out by the Black Saturday fires.

Three months after the fire there were no seedlings of the Shining Nematolepis to be found and it was feared  the species might now be extinct in its natural habitat. Thankfully seed had been collected as part of the Millenium Seed Bank Partnership, a project involving Royal Botanic Gardens Kew and many environmental organisations around the world, including most botanic gardens in Australia. (That's the link to Royal Botanic Gardens Kew!)

A good representative sample of the 200 plants was, and is, held in the Victorian Conservation Seedbank, with duplicates sent to Kew. All up, an insurance policy of 16,000 seeds.

So was it time to cash in that policy? Turns out not. Come spring of 2009, thousands of healthy seedlings appeared near Marysville. As the Kew site notes "although this is not a surprising response for the hard, black-seeded Rutaceae...there were fears that owing to the intensity of the fires and the deep-burning of the humus-rich soils...the soil-stored seed bank might have been destroyed".

For added projection, the seedlings have been fenced from animal damage (including accidental damage by the human species).

There is also the cheery report of a new population discovered. Parks Victoria staff were out checking on the well-being of the rare Broad-toothed Rat, also an inhabitant of the area burnt on Black Saturday. They found a small population that had been mostly burnt in the fires but with a "handful of surviving adult trees" and "numerous seedlings".

Seed from the new population will be collected in due season to improve the genetic representation in the Seedbank.

Image: The forests around Marysville when I drove through in spring 2009.

Wednesday, 15 September 2010

Cadi Jam Ora Garden continues to provoke and inspire

I've been surprised by a lot of things during my twelve years in Sydney. I came up from Melbourne a little unsure of the city and its people but both have exceeded expectations (of course some improvements could be made in each but this isn't the place to dwell on such things).

My first surprise was that the Olympics were actually fun. I had planned to find an excuse to travel back to Melbourne during September 2000 but ended up enjoying the excitement, variety and even some of the sport...

A big surprise closer to home (or work) was the Cadi Jam Ora - First Encounters Garden in Sydney's Royal Botanic Gardens. Some visitors find the storyline confronting and challenging but almost without exception they read it. The Garden is situated next to the First Farm, where European agriculture and horticulture began in 1788, and is an important addition to interpreting the history and importance of this place and of its plants.

It's just over ten years since the first plantings in this provocative and inspiring garden, telling the story of Aboriginal history in this country with an emphasis on the Gadigal (or Cadigal) people of the Eora nation.

A community planting day was organised for 9 August 2000 - United nations International Day of the Worlds Indigenous Peoples - with elders and students from Plunkett Street Public School, Redfern Public School and Soldier Settlers public school participating. We hope to have some of them return today to celebrate the garden's first decade and to plant an Angophora costata seeded from a remnant tree in the Yurong Precinct of the Domain. Other plantings will be from the 2000 list, included at the end of this posting.

We believe the 'Cadi Garden' was the first public garden to recognize local Indigenous history and culture in Australia in such an overt way. It followed closely the appointment of the Botanic Gardens Trust's first Aboriginal Education Officer, John Lennis, in 1999. John's role was critical in establishing close relationships between elders, local communities and the Gardens.

Today each of the three botanic gardens run by the Botanic Gardens Trust employs Aboriginal education officers, has an identified Aboriginal apprentice, and runs Aboriginal guided tours.

The Cadi Garden won the Interpretation Australia National Awards for Excellence in Heritage Interpretation 2002, and has become the focus of a wide range of educational programs about Aboriginal culture, history and plant-use.

The Parliament of New South Wales voted last week to change the constitution preamble to recognize Aboriginal people as the State's first peoples. So reconciliation continues, albeit with plenty still to do. I would hope that the Cadi Jam Ora - First Encounters Garden is a place where reconciliation can continue to flourish.

*     *     *

This is the original planting list for the Cad Jam Ora - First Encounters Garden, with local Aboriginal names in bold where they are known.

Eucalyptus piperata ssp. piperita Sydney Peppermint
Eucalyptus tereticornis Forest Red Gum
Eucalyptus resinifera Red Mahogany
Corymbia gummifera Red Bloodwood
Angophora costata Smooth-barked Apple Marridugara
Syzigium paniculata Brush Cherry Daguba
Achmena smithii Lillypilly Midjuburi
Cupaniopsis anacardioides Tuckeroo
Backhousia myrtifolia Grey Myrtle
Casuarina glauca Swamp Oak Guman
Casuarina cunninghamiana River oak
Melaleuca linarifolia Paperbark Budjur

Rapanea variabilis Muttonwood
Acacia terminalis Sunshine Wattle
Acacia longifolia var. longifolia Sydney Golden Wattle Wadanguli
Acacia longifolia var. sophorea Coast Wattle
Banksia ericifolia Heath Banksia Wadanggari
Banksia serrata Saw-tooth Banksia Wiriyagan
Banksia spinulosa var. spinulosa Hairpin Banksia
Grevillea linearifolia White Spider-flower
Grevillea buxifolia ssp. buxifolia Grey Spider-flower
Grevillea sericea Pink Spider-flower
Grevillea speciosa var. speciosa Red Spider-flower
Persoonia pinifolia Pine-leaf Geebung Mambara
Lambertia formosana Mountain Devil
Kunzea ambigua Tick Bush
Pimelea linifolia ssp. linifolia Slender Rice-flower
Angophora hispida Dwarf Apple
Melaleuca nodosa Ball Honey-myrtle
Polyscias sambucifolia Elderberry Panax
Carpobrotus glaucescens Pigface
Ficus coronata Sandpaper Fig
Gahnia sieberiana Red-fruited Saw-sedge
Rubus hillii Broad-leaf Bramble
Rubus hillii Native Rasberry
Livistona australis Cabbage Palm Daranggara
Callicarpa serratifolia Black Wattle
Eleocarpus reticulatus Blueberry Ash
Blandfordia nobilis Christmas Bells Gadigalbudyari
Patersonia glabrara Leafy Purple-flag Bugulbi
Podocarpus spinulosus Spiney-leaf Podocarp
Dianella caerulea Paroo Lily
Dianella revoluta Spreading Flax Lily
Lomandra longifolia ssp. longifolia Spiny-headed Mat-rush
Gymnostachys anceps Settlers Flax
Geranium homeana Cranesbill
Dendrobium speciosum var. speciosum Rock Orchid Wargaldarra
Tetragonia tetragonioides Native Spinach
Dodonea triquerta Native Hop Bush

Xanthorrhoea media Grass Tree Gulgadya
Macrozamia communis Burrawang
Telopea speciosissima Waratah Warada

Themeda australis Kangaroo Grass Bamuru
Danthonia linkii Wallaby Grass

Hardenbergia violacea Purple Twining-pea Waraburra
Billardiera scandens Apple-berry
Smilax glyciphylla Sweet Sarsparilla
Clematis aristata Old Man’s Beard
Clematis glycinoides Old Man’s Beard
Stephania japonica var. discolor Snake Vine
Cissus hypoglauca Flat-leaf Water Vine
Eustrephus latifolius Wombat Berry

Blechnum cartligeanum Gristle Fern
Cyathea australis Rough Tree-fern
Pteridium esculentum Bracken Gurgi

*     *     *

Images: At the top, the Cadi Jam Ora - First Encounters Garden today (in fact, 2007), and just above, the first plantings in 2000.

Sunday, 12 September 2010

Covering Portugal in Algae Would Fuel Europe

I've often asked whether algae will save the world. Yes really!

As an algal scientist by trade - a phycologist - I think algae are pretty cool. They look great under a microscope, which is something you can't necessarily say about us. They grow pretty much everywhere in the world. They come in almost every colour and size. And they soak up more carbon dioxide than trees.

The recent questions about world-saving, though, are to with their conversion into biofuel. As someone who discovers and celebrates algal diversity, I'm more interested in them before they are ground up and poured into our fuel tanks.

Still we can all love algae in different ways and I'm more than happy for algae to provide a solution to the peak oil crisis, climate change and any other of our human-induced ills.

About 40 years ago, during the American oil crisis, scientists first started to convert algae into biofuel. This work faded into the background during the 1990s when oil prices dropped, but has become quite the fashion in recent years.

There was a good review in a recent ABC Science Show which concluded that algal oil was a long way off as plane (or rocket?) fuel.

In the 13 August 2010 issue of Science two Dutch researchers, Rene Wijffels and Maria Barbosa, concludes that production of algal biofuels will be sustainable and economic within 10 to 15 years. The only problem with this prediction is that the 10 to 15 years timeline has been rolled out quite a few times, over the last, say, 10 to 15 years.

The traditional concept has been to extract oil from algae grown in ponds using waste carbon dioxide from coal-fired power plants, which sounds appealing. And in recent years vertical panels have been used to increase the efficiency of converting sunlight into algal growth.

To give sense of the problem, and the potential, Europe needs about 0.4 billion cubic metres of fuel ever year for transport. To supply this from algae would require just over 9 million hectares, about the size of Portugal and based on amount of sunlight a place like Portugal experiences every year.

Now that's fine for everyone but those living in Portugal, who may not like to live and work amid the slime. So scientists are looking at making the process more efficient. They note that production of penicillin by fungi is 5000 times more efficient than it was 50 years ago. Algae is still a relatively new crop.

There is potential for the usual kind of breeding and selection that takes place in all agriculture, aided these days with molecular techniques. It will also be important to combine oil extraction with bulk chemical, food and animal feed production. Water will be a limiting factor but it can be recycled and many algae can grow in salty water.

So lots of potential but also lots of science and development to do. Maybe in 10, or 15, years we'll only need to cover The Netherlands in algae to fuel Europe.

To read more you'll have to visit your local university library or pay to download from ScienceMag.

Image: This could be Lisbon if Portugal decided to provide all of Europe's transport fuel needs... The picture is a mock up of a field of algal bioreactors from the Energy Power Shift site.

Saturday, 11 September 2010

Mountain Biking a First for Mount Annan Botanic Garden

In what I believe is a world first (I await a correction from some far flung botanic garden reader) Mount Annan Botanic Garden now has an Enduro Trail.

For those of you not up with your mountain bike lingo, an Enduro Trail is something you endure, for pleasure.

I was out at Mount Annan this morning to help Caz McCallum open the first stage of what will be a 14 km track. The track zig-zags its way between the M5 Motorway and the top of the hills along the eastern side of the botanic garden.

To create the track, weedy African Olive and Privet were cleared and gullies crossed by bridges or rocky pathways.

The first riders were very happy with the result. Some fine tuning, of course, but overall the rated it highly and all said they will return.

At the moment two loops of the track are available to riders, the Competent and Intermediate. The Competent loop is designed for folk of moderate fitness and bike skills. The Intermediate loop is for riders who have "completed a number of mountain bike trails, have a moderate fitness level and are competent on an off-road bike".

The next stage will be the Advanced loop, for those primed on the first two loops to improve their fitness and skill levels - or who arrived fit and skilled!

Mount Annan’s terrain, vegetation and location make it an ideal cycling venue. The gentle hills are just right for a good cardio workout. And as your heart beats, enjoy the vegetation changes from open paddocks to groves of native Australian bush. Then there are the BBQs and picnic areas nearby, plus the rich horticultural collections of the botanic gardens 'proper'.

This is just the first part of making Mount Annan Botanic Garden the world's favourite botanic garden for cyclists. We have 'pump tracks' planned (you can look this up on your favourite search engine) as well as a regional cycleway across the garden. It's worth mentioning that the local champion for these cycling facilities at Mount Annan is Manager of Horticulture, Dan Bishop.

In case you are planning a visit, the trail is open daily (except Christmas Day) during the Garden’s operating hours - 10 am to 5 pm. If you want to ride around dawn and dusk, join the Friends and get not only free-entry during hours but non-vehicular access when it's light.

Riders must wear an Australian Standards (AS/NZS 2063) bicycle helmet and obey track rules and regulations, particularly 'keep to the tracks. There is a very nice map available - just visit the Botanic Gardens Trust website.

Images: Pictures from today's opening, plus the following gratuitous picture of our seasonal wildflower display near the entrance.

Friday, 10 September 2010

Our Ozzie Nut*

Last year I was invited to a celebration of the world’s oldest cultivated macadamia tree, planted 150 years ago in Brisbane’s City Botanic Gardens. Unfortunately I couldn’t attend the celebration but we have a pretty elderly specimen of Macadamia here in the Royal Botanic Gardens.

I’m not sure what species of Macadamia the ‘Walter Hill Tree’ in Brisbane is, but there are two widely in cultivation and used to produce macadamia nuts. Our one is Macadamia tetraphylla, producing festoons of tiny purple flowers in September.

The other is Macadamia integrifolia, with leaves in whorls of three rather than four. Both species are native to rainforests in southern-eastern Queensland, with Macrodamia tetraphylla extending down into New South Wales.

Although macadamia nuts were harvested and eaten by local Aboriginal people, as is well known, they were first brought into commercial cultivation in Hawaii, in 1882. Apparently Australian botanists promoted their potential as far back as 1900 but it wasn’t until 1963 that Australia entered into production.

The invitation from Queensland said the Walter Hill Tree represents the birth of Australia’s macadamia industry now worth over $100 million annually and earning over $70 million in exports. The industry is as old as the State, now 151 years.

According to the media release, the macadamia nut has been called Queensland’s Gift to the World, by Queenslanders, and the King of Nuts by those around the world who know and love it.

The macadamia nut is the only native Australia food to be internationally traded and is currently exported to over 40 countries.

There are other species of Macadamia in Australia, some of them quite rare, and a number of cultivars bred from the commercial species – some of these will flower twice a year, producing two crops.

By the way the name ‘Macadamia’ honours a chemist and academic from Melbourne, John Macadam. He was also Member of the Legislative Assembly for Castlemaine, a town in central Victoria, and my home town.

Images: Two pictures of the Macadamia tetraphylla in Sydney's Royal Botanic Gardens.

*This Passion for Plants posting will also appear on the ABC Sydney website (under 'Weekends' or search 'gardening'), and is the gist of my 702AM radio interview with Simon Marnie on Saturday morning, between 9-10 am.

Saturday, 4 September 2010

Blue Waratah Wonderland Solution Won't Save Blooms from Poaching

Alice wondered why the playing cards in the Queen's garden were painting the white roses red. Sydneysiders might have wondered why scientists were painting red waratahs blue.

I can confirm it had nothing to do with State of Origin. In fact, it was a cunning plan to stop the illegal harvesting of waratah blooms from bushland on New South Wales' Central Coast. A plan that didn't work.

Doug Beckers from the Parks & Wildlife Division of our State's Department of Environment, Climate Change and Water, and Cathy Offord, from the Botanic Gardens Trust, were testing a curious solution to a crime that threatens the survival of some populations of Telopea speciosissima - flower poaching.

Beckers and Offord began by painting 100 waratah blooms blue with Berger Paints 'Burton Blues' low sheen acrylic, leaving 200 unpainted as 'controls'. The hypothesis was that the blue paint would reduce the commercial value of the 100 blooms (around $12 per stem at the florist) and they would be left intact.

Well, the Burton Blues, if I can call them that, were poached slightly less often than the unpainted blooms and overall the total number of blooms 'borrowed' in the test year was slightly less than the previous year. That said, around a quarter of the stems were still ripped off.

Not surprisingly painting the flowers blue reduced fruit set - what self-respecting pollinator would be seen hovering around a Burton-Blue-low-sheen-acrylic coloured pollen trap? That said, plants with a single bloom had a reasonable fruit set in painted specimens, which is odd.

Although painting blooms blue detered the collection of those particular flowers a little, it didn't have much impact overall. Sensibly, Beckers and Offord recommend that painting not be continued.

What might be hard to understand is why any of the Burton Blues were poached. Surely they wouldn't have any value as a cut flower. Beckers and Offord suggest that thefts may take place in the night, to avoid detection, when the blue hue may not be as obvious. Perhaps an irridescent paint could be tried?

So what can we do to protect these plants for criminal vandalism? The authors suggest some kind of surveillance, perhaps even a 'Waratah Watch' program by locals.

If you want to read more about this study, see the latest issue of the Botanic Gardens Trust's ecological journal, Cunninghamia (volume 11, number 3, pages 287-293). The full issue will appear on-line in due season (probably 'sprummer).

Images: The picture at the top is my feeble attempt to create a blue waratah bloom. Below is Cathy Offord sizing up a waratah bloom, perhaps considering how it would look in Burton Blue.

Thursday, 2 September 2010

Kimberley, Blooming Wet

One week in the Kimberley during the wet season, 10-20 plants new to science. That's the tally from a field trip to the Prince Regent River Reserve and Lawley River National Park in March this year.

While from my recent and only experience in the region, I'd suggest that July is the 'wet season' I won't quibble. Matt and Russell Barrett have been exploring the Kimberley since they were teenagers, growing up on a local family cattle station.

For the last 12 years they have worked as scientists at Kings Park & Botanic Garden in Perth, and have been keen to explore the Kinberley in peak flowering seasons, during The Wet.

The story of their exploits is in the latest (No. 70, winter 2010) issue of For People & Plants, the Friends of Kings Park quarterly magazine.

The Barretts used aerial photography on Google Earth to pick potential collecting sites, finding safe places to land and good habitat variation. Anything to minimise the cost of helicopter time at $15 per minute.

They found on average two novelties a day, with a total of 10-20 new or interesting species. It may take months, or even years, to confirm which are new to science, new to the State or 'extreme variants'. All of which are interesting to scientists and for conservation.

The highlights include a new 50 cm high Boronia, a new scrambling Hibbertia, two new Calytrix species, three new Triodia (spinifex), three new Stylidium (trigger plants), a new Calandrinia and even a new Acacia (wattle).

They confirmed a species first discovered in 1821 by previous Director of the Sydney Botanic Gardens, Allan Cunningham. Aruranticarpa resinosa had not been seen for 180 years until rediscovered in 2001, but only as juvenile plants. Plants in fruit, as seen by Cunningham, were discovered a few years later but it was only on this trip that flowers wer collected for the first time - 'white large bunches...[with]...a beautifully sweet purfume'.

The Barretts also 'rediscovered' the Kimberley Lemon Myrtle, a new species of Backhousia, a genus otherwise only known from the east coast (Queensland and New South Wales).

These new finds come on top of 15 new species found during a trip with the Western Australian Museum in January and its thought there might be another 500 species to be found. Most of the new species are rare and need protection from inappropriate fire, overgrazing and possibly future development of the area.

Image: A Kimberley landscape between Broome and Cape Leveque from my recent trip.

Wednesday, 1 September 2010

Truly Tremendous (Tiny) Trees

This Dragon's Blood Tree in Sydney's Royal Botanic Gardens, but not its offspring, would be on some lists of magnificent/remarkable/signficant trees of the world. Sadly, as I reported some time ago, the parent tree no longer looks like this and its 'Safe Useful Life Expectancy', to use the technical term, is rather short.

There are books on remarkable trees, registers of the largest ones, and plenty of postings of people's favourites - I quite like this 2007 posting of the ten (plus some extra...) 'most magnificent trees in the world' even though there is a lot of human interference here that may not be to everyone's taste.

I started searching through these lists on the weekend after a lawyer from Pakistan, Imran Abbes, mentioned to me a Banyan Tree growing near his hometown in Midh Ranja, Pakistan. He said this specimen, called I think the Bergad (or Bargad) Tree, is one of the biggest and oldest trees in Pakistan, and perhaps the world. At 500 years it may be one of the oldest in his country but there are older and most likely larger fig trees elsewhere. In any case, Imran will send me a picture after he returns home and I'll post that later.

The problem, I find, is that most of these compendia concentrate on old and big trees. The Dragon's Blood Tree (or Dragon Tree or Dragon Blood Tree; Dracaena draco) above is moderately old at 100 or so years, and relatively big for this species. It's a lovely specimen and perhaps one of the favourites in our botanic garden. But should we start loving one of the seedlings (pictured above) that may have to replace it one day?

There seems to be little time or inclination to enjoy a tree in its youth. And as our Dragon's Bood Tree story demonstrates, every magnificent tree has a start and an end.

As an aside, I've given a talk a couple of times about 'why plants are immortal', where I explain the ideas of French botanist Francis HallĂ©, who argues that the length of life of a tree is "only limited by unfavourable external conditions: earthquakes, bad weather, diseases, large predators.” He bases this conclusion on a view that trees are in fact colonial organisms and that each growing tip can be considered an individual - so the tree itself is a collection of individuals that lives as long as it's scaffolding (which he equates to a pile of 'excrement' - wood being primarily waste products of the growing tips...) survives.

Anyway, the reality is that trees to die and our lists much continue to be updated. However I'd like to see a few youthful sprouts added to these lists and I give you two suggestions here.

This is a White Fig (Ficus virens) planted to replace the ten Moreton Bay Figs removed along Hospital Road in Sydney's Domain, in 2004.

This was significant for me of course given the misinformed and misguided campaign at the time trying to stop us do what we do every day - care and manage the plants in our estates, taking into account the past, present and future. This is the beginning of a collection of trees that all the kids in this picture will enjoy through their lives.

And the second example is a pretty obvious one, the first Wollemi Pine grown in cultivation. It was planted in Sydney's Royal Botanic Garden in October 1996, two years after its discovery in a remote canyon north of Sydney. Thanks to the propagation research by our scientists at Mount Annan, and the commercialisation and distribution program by Wollemi Australia, this species is now growing in gardens all over the world. The tree remains threatened in its natural habitat due to low numbers and the risk of fire and disease but the species itself is unlikely to go extinct. So this 14-year-old tree is worth celebrating.

I'm sure there are lots of other remarkably magnificent young trees.