About Me

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Canberra-based naturalist, conservationist, educator since 1980. I’m passionate about the natural world (especially the southern hemisphere), and trying to understand it and to share such understandings. To that aim I’ve written several books (most recently 'Birds in Their Habitats' and 'Australian Bird Names; origins and meanings'), run tours all over Australia, and for the last decade to South America, done a lot of ABC radio work, chaired a government environmental advisory committee and taught many adult education classes – and of course presented this blog, since 2012. I am the recipient of the Australian Natural History Medallion, the Australian Plants Award and most recently a Medal of the Order of Australia for ‘services to conservation and the environment’. I live happily in suburban Duffy with my partner Louise surrounded by a dense native garden and lots of birds.

Thursday, 29 June 2017

On This Day, 29 June; Rembert Dodoens and Dodonaeas

Rembert Dodoens is probably not a name that features regularly in your life, and fair enough too, but he made a contribution to the Australian botanical landscape in particular (plus quite a few others in a more minor way), albeit with no intention of doing so. Indeed, having been born on this day, 29 June in 1517, he could have had no concept of 'Australia'. 
Rembert Dodoens, courtesy University of Mannheim; date and artist apparently unknown.
He began life in Mechelen, Flanders (now Belgium) and was clearly a bright lad; I doubted it when I first read that he began his university studies at Leuven (Louvain) at the age of 13, but several separate sources seem to agree on this. He graduated at age 18, when most modern students are just embarking on their studies, in medicine, geography and cosmography (the last being the science of mapping the universe, but please don't ask me to explain more precisely). He became the great herbalist of his time, which also meant a doctor. He spent 13 years as the court physician to the Holy Roman Emperor in Vienna, and ended his life as Professor of Medicine at Leiden. 

He authored several books, but by far his most famous and influential was his Cruydeboeck (ie 'herb book') which offered one of the earliest attempts at a classification, albeit only 'use-based'. Its value at the time however was that it summarised all known medicinal uses, contemporary and historical. It was translated into French as Histoire des Plantes, and into English as A new herbal, or historie of plants. Later Dodoens translated it into Latin, which led to it being regarded as a basic herbal text for the next 200 years. Other than the Bible, it was the most translated work of its time. 
Dodonaea boroniifolia, Tallong, New South Wales.
The papery three-winged fruits are characteristic and diagnostic of the genus.
It was in acknowledgment of that that Linnaeus named the genus Dodonaea for him in 1738. (As a curious taxonomic aside, the official credit for the genus name goes to Philip Miller in his Gardeners Dictionary Abridged Edition 4, 1754, who cites the earlier Linnaeus publication of the name. The  correct name for any species of plant is the first one published since 1753 – ie since the publication of Linnaeus' great Species Plantarum, in which he listed every plant name published in his two-name system that he knew of. The implication is that he left Dodonaea out of his opus - or perhaps he had only published the genus, and not a two-name species, so his name was unavailable to Species Plantarum? If you know the answer to this conundrum I'd be grateful.) It's not clear where Miller got his material, but it seems that D. viscosa was already being grown in England by then, which would explain why he published it in a gardening dictionary.

Dodonaea is the largest genus in the world-wide family Sapindaceae, which also includes maples, rambutans, tamarinds and lychees. The seventy or so species are all found in Australia, but one, D. viscosa, a highly variable species, has spread throughout much of the world - not by human intercession as has been widely believed and reported, but in the last couple of million years. Presumably the small wind-distributed seeds made this possible but it does seem remarkable. 

D. viscosa, Inca Track, southern Peruvian Andes;
Europe is the only unfrozen continent where this remarkable species does not grown naturally.

D. viscosa fruit, Great Sandy Desert, Western Australia.

D. viscosa immature fruit, Black Mountain NR, Canberra.
In Australia many other genera in the family are trees, both in rainforests and arid lands. 

Here members of the genus Dodonaea (which is widespread, common and familiar) are known as hopbushes, as the bitter fruits were used in place of hops in beer-brewing. (I'm pretty sure that this is true, though some sources suggest the name only reflects an apparent similarity to hop fruit.) I have read that they were also used in baking in place of yeast, but I can't imagine how that might have worked or what effect it might have had on the flavour of the bread!

The flowers are wind-pollinated, and have no petals or nectar. 
D. viscosa flowers, Gawler Ranges NP, South Australia.
I'm sorry that Rembert Dodeons didn't ever see or even hear of the plant named for him. I hope he'd have appreciated them; after all, even if he was only interested in their utility, he would surely, as an inhabitant of what was to become Belgium, valued their contribution to beer in the Antipodes!

Here are a couple more, to end with. I hope you've enjoyed meeting them and the man who unwittingly gave them their name. If so, you might like to raise a glass to him to acknowledge his birthday.
D. lobulata, Whyalla Conservation Park, South Australia.

D. stenozyga, Yalata, south-western South Australia.

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Thursday, 22 June 2017

Alone in the World; single species families

I've long been intrigued by organisms which have no close relations, having separated off from their ancestral line very long ago. I'm not just talking about animals and plants which are the only ones in their genus - indeed it is claimed (and I've not attempted to verify it!) that there are more animal genera with just one species than of any other number! I'm talking about a whole family with only one genus, which in turn has only one species. What this means is that the species has been alone with no close relatives for millions of years, and almost certainly ten of millions. 

This in turn means - at least it seems so to me - one of two things, though I've never actually read a discussion of it. Either the species has been living for a long time in a very stable environment, and perhaps in a small area, so that it hasn't ever split into separate populations which in time evolved into separate species, or all its sister-species for some reason became extinct. However that's as far as I'm going the pursue the 'whys' today, preferring to introduce you to some of these special species and simply admire them. 

At the end I'm going to go a step further and offer you some really ancient animals and plants which are the only survivors of an entire Order!

There are about 30 singleton bird families of the 230-odd living families recognised. I have chosen to use the International Ornithological Congress (IOC) list as my standard taxonomy, in large part due to their excellent website which is updated (with explanations) every three months. Let's meet some of them.
Family Dromaiidae.
Emu Dromaius novaehollandiae father and chicks, northern Flinders Ranges, South Australia.
This one is perhaps borderline, as two Emu species - from Kangaroo Island and from King Island in the Bass Strait
between Victoria and Tasmania - may have become extinct in the early years of the 19th century.
The 'may' does not refer to any doubts over their extinction, sadly, but to whether they were indeed
full species. Many think they were (including me for what it's worth) but IOC does not.
Family Anseranatidae.
Magpie Geese Anseranas semipalmata, Territory Wildlife Park, south of Darwin (but these are wild birds).
A strange Daffy Duck lookalike, with knobbed head, half-webbed feet and odd breeding habits, whose ancestor
apparently split from the waterbird line before the extinction of the dinosaurs 65 million years ago, long before
the more modern ducks/geese/swans family arose.
Once found across south-eastern Australia, now common only in the tropics of Australia and New Guinea
(though I feel that they're making a slow recovery in the south).
Family Scopidae.
Hamerkop Scopus umbretta, Entebbe Botanic Gardens, Uganda.
Widespread in sub-Saharan Africa and Madagascar, its resemblance to herons is coincidental.
Its closest relatives are probably pelicans and the Shoebill (coming up) but flamingos
seem to be in there somewhere too...
'Hamerkop' is from Afrikaans meaning 'hammer head'.
Family Balaenicipitidae.
Shoebill Balaeniceps rex, Murchison Falls NP, Uganda.
A remarkable bird and a large one, up to 1.5 metres tall, found in swamps of central eastern Africa.
The huge sharp-edged bill apparently evolved to eat large fish, notably catfish and lungfish,
but frogs and reptiles, including monitor lizards and young crocodiles, are also taken.
Family Eurypygidae.
Sunbittern Eurypyga helias, Manu Special Reserve, Amazonian Peru.
A lovely bird which has only recently lost its even more special status as a single-Order bird,
being now placed in the same Order as an another member of the single-family club, the equally enigmatic
Kagu of New Caledonia.
Family Aramidae.
Limpkin Aramus guarauna, Manu Special Reserve, Amazonian Peru.
It looks rather like an ibis, but is apparently closest to (though still distant from) the cranes.
It is found throughout eastern and northern South America, central America and the Caribbean, and Florida.

Family Pluvianidae.
Egyptian Plover Pluvianus aegyptius, BenouƩ NP, central Cameroon.
Once thought to be an aberrant pratincole, it is now recognised as being somewhere near
the true plovers and painted snipes.
It is found by rivers in a band across Africa south of the Sahara.
Family Steatornithidae.
Oilbird Steatornis caripensis, Yasuni NP, Ecuadorian Amazonia.
A remarkable fruit-eating nocturnal bird - the only one in the world - from the north of
South America. They nest in caves and are among the very few birds to echo-locate.
They seem to be closest to the frogmouths and nightjars, as theirs superficial appearance seems to suggest,
but there are some who would put them in their own order.
This one remarkably appeared above our canoe on a creek one night.

Family Donacobiidae.
Black-capped Donacobius Donacobius atricapilla, Yasuni NP, Ecuador.
This one is the unwitting cause of considerable controversy; until recently it was thought to be
an unusual mockingbird, then a wren, but current thinking puts it in its own family (though not all agree)
with its nearest relations being in Africa. A bold, curious bird found along waterways throughout much of the
northern half of South America.
Family Coerebidae.
Bananaquit Coereba flaveola Umbrellabird Lodge, southern Ecuador.
Another controversial one, which has been swapped between the tanagers, to a sorry 'unknown status',
to being placed in its own family, though again not all yet agree with this.
It's a bold familiar little bird around lodges and feeders across northern South America and the Caribbean.
'Quit' is apparently a Jamaican-English name for a small bird, but there the trail of its origin ends!
We'll come back to one more remarkable single-species bird family towards the end, but meantime, how about mammals? There are relatively few compared with birds, but there are some familiar ones, and Australia has more than its share.
Family Ornithorhynchidae.
Platypus Ornithorhynchus anatinus, Tidbinbilla Nature Reserve, near Canberra.
One of only two groups of monotremes (along with the four species of echidnas), the
only egg-laying mammals. It is also, along with the Water Rat, the only fully aquatic endemic
Australian mammal.
Family Phascolarctidae.Koala Phascolarctos cinereus, Mount Eccles/ Budj Bim National Park, Victoria.
(And I can't believe I don't have a better picture than this!)
The ancestral koala parted from its relatives that were to become the two species of living
wombat (and many extinct ones) some 40 million years ago.
Family Myrmecobiidae.
Numbat Myrmecobius fasciatus, Perth Zoo.
A termite specialist, once found across southern Australia but now restricted to a few isolated
colonies in the south-west. It is placed with the Australian marsupial carnivores, and was possibly
closest to the sadly late Thylacine, but its ancestor seems to have gone its own way more than
30 million years ago.
Family Thylacinidae.
A moving tribute to the magnificent big marsupial carnivore, Launceston, Tasmania.
It was deliberately driven to extinction in the 1930s in Tasmania, having been extirpated on
the mainland with the arrival of the Dingo some 4000 years ago.
(I wrote about it in more detail some time ago, here.)
 Family Dugongidae.Dugongs Dugong dugon, Shark Bay, Western Australia; you rarely if ever see a whole one at once!
There are only four members of the Order Sirenia; the other three, the manatees, form a separate family.
The Dugong is found in warm shallow seas from Australia and through south-east Asia,
as well as on the east coast of India and the east coast of Africa.
The sirenians are the only fully vegetarian marine mammals.

The old South American rodents are an ancient group, having arrived from Africa by rafting some 30 or more million years ago, like the South American monkeys. A couple of large aquatic species form their own families.
Family Myocastoridae.
Coypu Myocastor coypus, Chepu River, Isla de ChiloƩ, Chile.
I wrote about them very recently here.
Family Hydrochoeridae.
Capybara Hydrochoerus hydrochaeris, Tambopata NP, southern Peru (plus a couple of Giant Cowbirds).
The world's largest rodent, up to 130cm long and weighing up to 65kg, living in groups of dozens.
Some would put it in the family Caviidae with guinea pigs, but I find the competing claim convincing.
(I hope to have a better photo by the end of the year!)
I don't think I can illustrate any singly-species plant families, though in Australia the Albany Pitcher Plant Cephalotus follicularis, Family Cephalotidae, is a good example.

Which brings us to the real isolates - sole members of an entire Order! Among mammals the wonderful Aardvark Orycteropus afer is the only one I can think of. Among reptiles the sole example (I am almost sure) is the ancient New Zealand Tuatara Sphenodon punctatus, Family Sphenodonidae, Order Rhynchocephalia. The key thing is that they are not lizards, but something far older.

Among living plants, the Gingko and the Welwitschia apparently fall into the category, though modern plant taxonomy can be pretty hard to keep up with!
Family Ginkgoaceae, Order Ginkgoales.
Gingko Ginkgo biloba, growing as a street tree in Canberra.
Native to China, it is known from 260 million year old fossils.
Family Welwitschiaceae, Order Welwitschiales.
Welwitschia Welwitschia mirabilis, Damaraland, Namibia.
(A scan of a faded slide, but this is too fascinating a plant to ignore!)
The plant comprises just two constantly-growing leaves, which are shredded by wind.
The plant can be almost 10m across. Individual plants are believed to be in excess of 1000 years old.
And we'll finish with a bird, one of just two species in the world which represent entire Orders (the other being the Cuckoo-roller of Madagascar, which I'm hoping to see in a few weeks!).
Family Opisthocomidae, Order Opisthocomiformes.
Hoatzins Opisthocomus hoazin, Tambopata NP Peru, above, and at dusk, Yasuni NP Ecuador, below.
A large but sluggish bird, found throughout the Amazon basin. Its somnolence is largely due to its diet;
it lives almost entirely on leaves, and is the only species of bird which digests leaves by bacterial action,
like a herbivorous mammal. The fermentation chamber is so large that it is has largely displaced the sternum,
the keelbone which anchors the great flight muscles, so it is essentially flightless.
Chicks can drop into the water to escape danger and dive and swim, climbing back out again with
the assistance of sharp claws on fingers two and three.
All this is pretty amazing, but they've had 64 million years of evolution to come up with
unique adaptations. They're one of the things I most look forward to when I go back to the Amazon.

There are very many wonderful and surprising things in this wonderful and surprising world; among them are the organisms without close relatives. I hope you've enjoyed meeting a few of them.

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Thursday, 15 June 2017

Australia: Living in a Land of Fire

Over most of Australia (excepting perhaps only the rainforest pockets and the alpine systems) fire is a natural, even essential, part of the ecology, and has been so for at least 20 million years since the land began to dry out and the narrative of receding rainforests and expanding dry forests, woodlands and grasslands began to unroll. During the current Quaternary Ice Age (ie the past 2.6 million years) the typical 'modern' sclerophyll - ie hard-leaved vegetation - began to appear and fire became more dominant in the landscape.

Aftermath of a managment burn, Townsville Common, Queensland.
The presumption (still occasionally asserted) that fire in Australia is a human construct, or that fire ecology was human-sculpted, needs to be put into that context. If you were to drive across Australia from Perth to the east coast (some 3,300km), tracing the history of fire in the continent with kilometres as years, you would reach the start of human influence just 8km from the east coast. Even if we consider just the current ice age, the time of greatest fire influence, we would be within just 60km of the end of the journey before people entered the equation.

This is not to say that humans did not manage the landscape via fire, and influence it to varying degrees.
Managed burning of spinifex grassland, central Australia.
People used fire, in a very directed and sophisticated manner, to tilt the ecological balance in favour of large grazing herbivores, as well keeping portions of the country open for ease of usage and almost certainly even wildfire control. (It continues to be suggested that we should try to rediscover and employ indigenous fire management in national parks, but their management now is for an entirely different purpose from that of our management predecessors.) Over much of the country the knowledge has been lost, wholly or partly, but in some remote traditional areas it is still applied.
'Hunting burns', Great Sandy Desert, Western Australia, above and below.
People, (mostly women, I understand) of the Kwirrikurra community, burn small areas to expose
and flush out small animals, and to encourage a patchwork of habitats.

Before I leave this interesting and important part of the discussion, I must at least acknowledge the impact a recent book, The Biggest Estate on Earth by Australian National University historian Bill Gammage, has had on the debate. Meticulously using a wealth of historical accounts, he concludes not only that people managed the land, but did so at a continent-wide scale to the extent that no 'wilderness' remained by the time Europeans arrived. It is inevitably controversial, but has sparked a very valuable and ongoing debate. Bill's a former neighbour and ongoing friend, who I greatly admire, but I don't agree with all his conclusions, a situation which I see as perfectly normal and healthy. For a couple of randomly-selected and well-argued opposing reviews of his book, see here and here.

However, today I want to focus more on how plants have adapted here to surviving in this Land of Fire. Firstly however I should be more precise than I've been so far. Organisms and landscapes don't adapt to a fire, but to a fire regime, which is defined by intensity of 'normal' burns, their frequency and the season they usually occur. This is a much more complex evolutionary challenge. However there is no doubt that Australian ecosystems respond, and quickly, to being burnt, no matter how devastating the immediate aftermath may appear.
Burnt Mulga (Acacia aneura) woodland, central Australia.
Burnt Mulga woodland starting its recovery, north of Alice Springs.
Importantly, this was in the midst of an intense drought.
In January 2003, fires of a scale and intensity locally unprecedented in European times, burnt vast areas of the New South Wales and Australian Capital Territory mountain forest and adjacent lowlands - including over 500 homes in Canberra, the nation's capital. (I wrote in some detail about it here if you're interested, on the tenth anniversary of the fires; even now I don't find it easy to reread and I'm not going to revisit what I wrote then.) My photos of the immediate aftermath are few and muddily pre-digital, but the later shots of the recovery show both the immensity of the original event, and the wonder of the recovery.
Hypoxis hygrometrica flowering in an otherwise entirely blackened landscape.
I can truthfully say that in trips into the mountains in the days following the fires I didn't see a
single green tree. (Again, see the link above for more detail.)

Ten years later. The view west into the Goodradigbee Valley from Mount Franklin.
The original trunks of the Snow Gums are still dead, but they are vigorously regrowing from the base.
OK, so what actually happens to make the landscape recover? There are a couple of basic strategies at work, and both can be seen in this photo, taken in Morton National Park, south of Sydney, a couple of months after the fire in January 2013.
Both the seed cases retained on the trees, and the ground-sprouting, are part of the process.
For this purpose we can divide fire-adapted plants into 'sprouters' and 'seeders'.  The former survive (though all above-ground parts may be destroyed) by reshooting after defoliation; this epicormic growth is a ubiquitous characteristic of an Australian landscape.. Seeders are killed, but regenerate from seed. In both cases, only mature plants are expected to be able to respond in this way.

The buds from which the shoots grow are there under the bark all the time, striving to burst forth but held sternly in check by the hormonal influence of the crown; these buds may be under the bark of branches and trunks, or under the bark of roots. When defoliation occurs though, (which may also be  through insect attack or drought, as well as fire), the buds are released to provide the necessary energy-fixing photosynthesis until the crown recovers. At this point the hormonal block is re-imposed and the shoots die back.
Epicormic growth, Morton NP, above and below.

New epicormic growth on Red Stringybark Eucalyptus macrorhyncha,
Aranda Ridge, Canberra
 As suggested in these photos, epicormic growth is mostly a eucalypt trick, but not exclusively. One of the requirements of this strategy is very thick or heat-resistant bark. While outside temperatures may be 400 degrees C, millimetres away beneath the bark the temperature may be only 40 degrees C.
Epicormic growth on Broad-leafed Geebung Persoonia levis, above, and
Leptospermum sp., below, Morton NP.

After the 2003 fires I was surprised to see widespread epicormic growth on River Oaks, Casuariana cunninghamiana. More recently my friend Martin reported such growth on acacias after a fast-moving grass fire destroyed properties east of Canberra; some of his photos here

On the other hand underground buds are possessed by a range of plant species. Soil is an excellent insulator, and most – 95% in fact – of a fire’s heat rises, so underground is a good place to bury your fire insurance. Eucalypts again have developed this to a fine art, with most of the known eucalypt species having ‘lignotubers’ – a massive woody subterranean structure bearing repressed buds that function in much the same way as the epicormic ones. For subterranean root buds of shrubs in particular, the inhibiting factor seems to be the existence of the stem. When it dies, root suckering commences.

Eucalypts sprouting from underground lignotubers; these four photos were taken in Morton NP.

Lomandra formosa.

A sedge (sorry not to be more precise!).

Lomandra sp. (a lily relation, family Asparagaceae).
Which brings us to the seeders. Most flowering plant species have ‘populations’ of seeds as well as of living plants. There are two essential places to store these seedbanks; ie on the plant, or in the soil. In general obligate seeders which store seed in the ground are shorter-lived than those whose aerial seed banks die when the plant does. In the former case the seeds don’t ‘need’ their parents; in the latter they do. In addition to the ‘ash bed’ effect, providing nutrients for the seedlings and the relative absence of competition (especially from overshadowing mature plants), it has now been shown that burnt soil is ‘sterilised’ of harmful bacteria and fungi which inhibit seedling growth. Additionally, work pioneered in Western Australia has shown that chemicals in smoke can stimulate germination.
Seedlings in burnt soil, Morton NP.
Some species retain most of their seeds on the plant, in the fruit. Such seeds are themselves heat-sensitive, but are protected by well-insulated seed cases. Such species include Casuarina, Hakea, Banksia and some native conifers. This mechanism – of only dropping seed after a fire – ensures that spring seedlings are not destroyed by summer fires without having reproduced. However they must wait a few days before opening, so that the seed is not dropped and cooked.
Banksia cones, opened to drop a single seed from each capsule, Morton NP.

Casuarina cones, likewise having shed their seeds, Mullewa, Western Australia.

Petrophile sp., Morton NP.
Perhaps counter-intuitively, seeders tend to dominate the rarely burnt canopy of wet sclerophyll forests. They do not wait for a fire to seed though; in the case of the ash eucalypts (named not for fire association, but for a European tree with apparently similar timber), normally they do so annually but hold the accumulating seed on the tree for some years after flowering. At any moment there are several years’ crop of seeds on the tree. When the capsules’ pedicels die or are killed, as by fire, the seed literally rains down, saturating the capacity of seed-foraging ants to carry them all away. Normally we would not expect any of this seed to successfully produce a sapling that emerges from the understorey; it is only when the understorey has been cleared by fire that the seedlings can prosper. This is why an Alpine or Mountain Ash forest, unlike most other forests, eucalypt and otherwise, tends to comprise even-aged stands of trees.
Even-aged stand of Alpine Ash E. delegatensis, Namadgi National Park.
Most plants however constantly release seed as they produce it. For these species the seedbank is in the soil and the seed population may long outlive the generation of plants which produced it. Many such seeds – and this includes many wattles and peas – are unlikely to germinate without a fire. That is, they actually require a fire’s heat to initiate germination. It is only when such seeds are cracked by the fire’s heat that water can be absorbed and germination begins. 
Senna sp. post-fire seedling, Watarrka (Kings Canyon) NP, central Australia.
The corollary is that lower intensity fires leave the seed bank of at least some species to await the optimal conditions provided by the aftermath of an intense fire. Some such seeds are very long-lived; Acacia dealbata seeds are extraordinarily persistent and it is suggested that they might wait in the soil for centuries for a fire.

The seedbank of other ‘seeder’ species does not survive fire; either seeds are kept on the plant or on or close to the surface of the ground without a fire-proof safe. In these cases seeds must be introduced to the area from elsewhere after a fire. Examples are mistletoes (carried in by birds) and some daisies (blown from elsewhere).

Some species are triggered to flower by the fire effects, such as leaf loss, the ash layer, or the increase in light. Apart from these ideal conditions, the mass flowering and seeding may increase the chance of pollination, and of escape from seed predators. Such flowering is known as pyrogenic.
Goodenia bellidifolia flowering post-fire, Morton NP.
Some 16 Australian orchid species virtually never flower without the stimulus of a hot wildfire the previous summer. Many others are stimulated into a mass flowering in the spring after a summer wildfire. Drosera spp. (sundews) do likewise. 

The Undertaker Orchid Pyrorchis nigricans (the 'blackish fire-orchid'), never flowers except after a summer fire,
here in the Brisbane Ranges, Victoria.
The strange common name, and the species name, arose because the pressed specimens used turned black!
In the first summer after the 2003 fires in the Brindabellas, for tens of kilometres along the ridge of the range the ground was carpeted with Prickly Starwort Stellari pungens flowers; this is a common enough herb that one can usually find scattered through the understorey, but such a display had not been seen in the ranges before or since. Clearly untold millions of seeds had been waiting in the soil for an intense fire to release their potential.
In the summer following the 2003 fires, tens of kilometres of mountain roads were white with
starwort flowers, as far as one could see in both directions.
After a fire, the regrowing grass trees, Xanthorrhoea spp., produce a spectacular flower spike, bearing up to 10,000 seeds. Timing is important though. Xanthorrhoea will flower the winter after a summer fire, but if the fire comes later, the flowering may be delayed until the second winter.
Xanthorrhoea flowering spikes, Brisbane Ranges NP, Victoria.
Needless to say, this has been a very abridged and simplified version of a complex and intricate story, but it's one that everyone living here should be aware of - and of course elsewhere in the world there are equally wonderful stories of fire adaptation. I hope it's been of some interest.

And as ever, I welcome your response.

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