Education Articles1

In closing, next time you’re hiding out in the forest from whatever dominant paradigm you have challenged, don’t forget to appreciate the leaf litter that you are snuggled down in and wonder at all those marvellous little fungi on the log you’re using as a pillow. And as the Clash sang back in the 80’s “I fought the law-n and the law-n won, I fought the law-n and the law-n won” - well for now anyway!

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RAINFOREST 'SUCCESSION'
By Spencer Shaw

The beginning of the long process of succession commences with bare soil, as a result of landslip, fire, storm damage or tree fall.
As the forest regenerates the bare soil is quickly covered with young plants, then the process of succession begins as one stage in the vegetation gives way to another. Together, these stages form a succession.

PIONEERS - THE FIRST COLONISERS
On bare soil and in hot bright sunshine, the seeds which will germinate belong to species of the first stage of succession, the pioneers. In the shade of the surrounding forest, these species do not survive, and their nearest location may be kilometres away. Yet the seeds are there. Either they were already present in the soil, or they have travelled far. A full-grown pioneer plant produces large quantities of small seeds readily dispersed mainly by birds in our local area.
Their small hard-shelled, long-lived seeds wait for the opportunity of a break in the canopy and exposed soil to grow and in turn set seed again. Wherever there is open soil, pioneers grasp their opportunity. They quickly produce a mass of foliage on weak stems, cast shade and leave litter on the soil (thus enriching it), and may just as quickly die. Other species, ones that do not need light quite so much when they are young, take their place.
Typical species are: Omolanthus nutans, Macaranga tanarius, Pipturus argenteus.

SECONDARY SPECIES - THE NEXT STAGE
We call this vegetation "secondary" because it grows where the original, primary forest has disappeared. At first, secondary forest does not have structure. It is thick, but its vegetation is not strong or long-lived. Other types of vegetation can easily replace it i.e. environmental weeds. Secondary species often require the protection of the pioneers to germinate and grow and create the increased shade and humidity suitable for the germination of climax species
Typical species are: Polyscias elegans, Melicope micrococca, Guioa semiglauca

MATURE OR CLIMAX FOREST - THE CYCLE COMPLETED
Seed from the mature phase species is short lived and does not persist in the soil seed-bank. Therefore, seed of these species must come from a seed source forest that exists close by the regenerating gap otherwise the regeneration will at best stagnate at the pioneer or secondary stage, but most likely become dominated by exotic species i.e. Lantana and/or Privet. In the ideal situation, the forest will progress through the various stages of regeneration until a mature stage rainforest ecosystem is re-established. This process may take several hundred years to complete. The regenerative process will however only continue to progress from the initial pioneer and secondary species mix if there is a ready seed source of mature phase species close by. Mature forest is made up of ancient trees that will last as individuals in excess of 800 years.
Typical species are: Argyrodendron trifoliatum, Sloanea woolsii, Ficus macrophylla.

References: Growing Rainforest - Rainforest Restoration and Regeneration. R. Kooyman.
Living Earth, livearth@gn.apc.org
Natural regeneration of the rainforests of Brisbane - Kenneth McClymont

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Sweet Dreams
By Spencer Shaw

When the sun goes down at the end of the day, what happens in the forest?
Many of us may think as we settle in for the evening that plants will also be taking it easy during the night – the hard day’s work of photosynthesis is over and surely it’s time for them to stand tall and relax! But this often isn’t the case. In the forest things are often just getting started - life for the trees is one big around the clock party!

So what is really happening out in the forest at night? Are the animals really the stars of the show? Or are they just bit-players in a much bigger drama? Are the animal’s mere pawns in a game that is being played out by higher life forms- that is to say the Trees (if you’ll pardon the pun)?
We know that fruit and nectar eating birds are on the day shift for spreading the seed and pollen of various trees and plants. However, we are often completely unaware (because we are curled up in front of the telly or in bed or both) of the important role our fellow mammals play in the dispersal and pollination workforce for our local forest plants at night. For instance are you aware that most eucalypt cross-pollination occurs at night courtesy of the much maligned, flying foxes. In a recent study of flying foxes Pteropus sp. it became apparent that eucalypt flowers where at their most receptive to cross-pollination during the hours of darkness. These trees rely upon flying foxes and other blossom bats to facilitate some serious genetic interchange over the vast distances that they travel in search of food. Some local eucalypts that attract nectar-feeding bats include Flooded Gum - Eucalyptus grandis, Tallow wood - Eucalyptus microcorys and the Pink Blood Wood – Eucalyptus intermedia.

Mammals aren’t the only creatures of the bush being enticed into working for the plants during the night. As the sun sets in the forest, the air can become thick with the intoxicating perfumes of some forest plants and although humans may appreciate these scents the real targets of these perfumes are the moths. Just like some humans use perfumes for the purposes of romance, these night time flower scents are designed to attract moths to their flowers and so spread their pollen from flower to flower – the moths thus play an unwitting role in the love lives of plants. The moths are rewarded with a small prize of nectar for their work, but not too much, just enough to get them to the next flower! Some night/evening perfumed flowers are Wilkea - Wilkea macrophylla, Native Jasmine’s - Jasminum sp., Mat rush’s - Lomandra sp., and Musk wood - Alangium villosum.
The flowers of the night are often white to reflect whatever light is available ie. “by the light of the silvery moon”. Flowers aimed at the moth demographic are often small simple flowers such as Chain fruit Alyxia ruscifolia, Banana bush Tabernaemontana pandaqui and Native currant Carissa ovata. Flowers aimed at the larger mammalian pollinators such as flying foxes, possums and many other nectar-loving marsupials often carry a larger reward of nectar to satisfy these sugar-hungry mammals. The flowers are brush-like in design to cover the snouts of the foraging animal in pollen. Flowers of the family Myrtaceae such as Eucalyptus sp., Syzygium sp. are typical of the flowers designed to attract mammals.

Crucial to the health of most forests is their relationship with mycorrhizal fungi. Mycorrhizal fungi actually engage in a symbiotic relationship with plant roots whereby they form a protective sheath over the plant roots and make more water and trace elements available to the plant through their hyphae (a fine network of tissue, that comprises the fungi feeding organ). In return, they receive carbohydrates from the plants. What has all this got to do with the night time activities of the forest, I hear you say? Now here’s the really amazing bit! Some of the mycorrhizal fungi have truffle like fruiting bodies. These truffles are an important food source for about 37 native mammals that include wallabies, bandicoots, rodents, potoroos and bettongs. The nocturnal bettongs and potoroos are specialist truffle eaters. Bettongs in particular have a specialised digestive system for making the most of the truffles they eat. The spores of truffles pass safely through the digestive systems of the animals and are deposited in a neat little fertiliser package ready to colonise new ground. These animals are crucial to the spread of some of these mycorrhizal fungi and in turn the fungi are crucial as a food source to the animals. What a wonderful case of mutual benefit!

However what happens when small marsupials such as the bettongs and potoroos become extinct in an area, due to habitat loss and feral animal predation? It could be speculated that not only do we lose some of our wonderful local fauna but that mycorrhizal fungi populations will be affected, by the loss of their main dispersal agent. Flowing on from that, tree health will be affected. The old analogy about ecology being like a spider web becomes more and more relevant in a story like this, because removing one thread often has serious effects on all the other threads and the web as a whole.

So we must all do what we can to maintain the diversity of our local ecosystems and be awed and thankful for the amazing local environment that we live and work in.

References:
Wildlife of Greater Brisbane, QLD Museum Publication
Tropical Topics, Wet tropics Management Authority
Thanks to Les Hall for his information re. flying foxes and eucalypt pollination and Jim Reside for his information on the importance of small marsupials and truffles.

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The Maleny Strangler Strikes Again
An over dramatic report by Spencer Shaw

Deep in the forests of Maleny is lurking a silent killer. The victims are often taken by surprise and their death is slow and drawn out.

But don’t worry too much, unless you do a Rip van Winkle and fall asleep for a few decades in the forest, these guys won’t be able to get a grip on you because these stranglers are Figs.
The main ‘strangler figs’ include Ficus watkinsiana Watkins fig, F. macrophylla Morteon bay fig, Ficus obliqua Small-leafed fig and also to a lesser extent Ficus virens White fig, Ficus superba Deciduous fig and Ficus platypoda Rock fig.

What a superb evolutionary step these guys have taken in the competition for life in the forest. Whilst all other trees start their life on the forest floor this particular group of trees has figured out a short cut to the canopy. They have the amazing ability to germinate not just in soil but in moist patches of humus high in the forks of branches on existing trees. You can imagine that life in the tree tops must become very dry after months without rain like we have seen recently, but somehow fig seedlings survive on what little moisture is taken from the air or that collects on the trunk of their host. This ability also makes them one of the few plants that can strike on rocky outcrops where moisture collects in fissures - Ficus virens the White fig can commonly be seen on rocky outcrops beside waterfalls throughout the Range.

The next task for the fig to complete after germinating high in an existing canopy tree, is to send roots down to the ground, just enough leaf is produced to provide the energy for this process. The survival of the fig depends on its roots reaching the forest floor and finding permanent water. Once that connection of root to soil is made, the days of the host tree are numbered (well the decades anyway - time moves bit slower in the plant world). Soil contact and permanent water allows the fig to rapidly accelerate its growth and send more roots down, these roots eventually surround host tree giving it an unintentional hug of death! *

Mature Ficus sp. that apparently start life in such a gruesome manner go on to become fountains of life within forests, through the massive quantities of fruit they produce. The fruit themselves are unique in that the flowers are born internally within the ‘fruit’ and are pollinated by remarkable mini-wasps that in turn complete their lifecycle within the ‘fruit’. The fruit provide a life sustaining supply of food to numerous birds and animals and are sometimes born in quantities that could possibly be estimated not by the kg but by the ton.
However before you race in to Barung and buy a fig to plant in your backyard, consider that amazing root system that these plants have and what they may do to your/or your neighbours drains or foundations. Their root systems can be expansive and are great at holding landscape together, but putting one in your backyard is like trying to keep an emu in a budgie cage – sooner or later something is going to give!

Acreage’s are best for these guys and they are one of those amazing plants that once established are incredibly hardy and will live on for centuries. Help make the future a better place and find a place in your world for a fig.

*Gosh it’s easy to slip into the ‘natures a battle field’ descriptions of natural processes. After watching obviously one too many of the Crocodile Hunter series (enforced upon me by my kids!) I imagine myself as an intrepid, if somewhat hyped botanist, battling through deep dark jungle, dodging flailing tendrils of lawyer cane, wrestling dangerous strangler figs and advising the viewers at home to never, ever try anything at home like this with their petunias.

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To Mow or not to mow, that is the question!
By Spencer Shaw

The year is 100,000 B.P., a cave man by the name of Ug McUg walks forth from his cave in the early morning light and ponders the day ahead of him. He notes with his still rudimentary thought processes that the grass surrounding the cave entrance is long. For the first time in history a curious thought enters his mind – “the grass out there is getting a bit too long, there could be snakes or other wild beasts hiding in it? I know I’ll cut it!” He fashions a rustic scythe from a branch and makes the worlds first lawn, and so begins the fall of man!
One of the greatest causes of the ecological disruption we are wreaking in Australia is our obsession with a so-called neat and tidy environment. Our local ecosystems are complex and diverse and can start to fall apart at the seams when we tidy them up.

Vast swathes of lawn may look attractive and appeal to certain needs, deep within our psyche, but not only are they a massive drain on the resources of the planet, they are sterile deserts when it comes to species diversity. Unlike Ug however we have no survival excuse for maintaining these ordered grasslands. We wiped out all the other creatures at the top of the food chain and don’t have to fear marsupial lion or giant goannas sneaking out of the undergrowth (but there’s still snakes of course - if your lucky). Our only excuse for the vast lawns and well ordered garden beds is that we are so wealthy (in real terms) that we can alter vast areas of land that would otherwise be home to complex self-maintaining ecosystems purely out of indulgence and not for survival or production of economic wealth.

Before I jump down of the soapbox (or get knocked off!) I’d just like to add that the usual characters that are blamed for threatening our local ecosystems such as the woody weeds (Privet, Lantana and Camphor laurel) are largely innocent. In fact they often have very little impact on overall ecological processes compared to the grass lands we indulge ourselves with for lawn or even dare I say it horse paddocks. The woody weeds may even have many positive effects on the local ecology, especially if they are spread by local wildlife.
Now before the Motor Mower Retailers of Australia Association take out a contract on me and try and put me six foot under the lawn. Or the local pony club decide to play an old fashioned game of polo with my head - I’d just like to add that I too have a spot of lawn (literally - we keep it in a pot in the patio and mow it with a set of hair clippers!).

Seriously now, small grasslands can be very useful for recreation and amenity values but do we really need as much as some acreage blocks maintain. Instead of scattered clumps of trees amongst our vast artificial grass lands I’d prefer to see scattered grassy clearings amongst ecologically diverse and complex forestlands.
Out at the Bunya Mountains National Park grassy knolls are found within the forest and were previously maintained by the local Murri’s fire stick farming practices. These grasslands are welcome sources of food for the local herbivores – but they also need the forest for food, shelter and water. It’s a matter of balance. Perhaps our own Bald Knob that we see at the front of the range was so named because it was a small patch of grassland amongst the dark forests of the Blackall range.

Now we’ve all been good little revegetators for the last few years and busily planting trees. The next thing we must learn to do is how to regenerate the understorey of our forests and even rehabilitate our native grass lands. See I’m not anti –grass, well actually you could even say I’m pro-grass, but that’s another story !! There are a whole swathe of fantastic native grasses and herbs we can encourage or plant. Suprisingly some grasses grow in or on the edges of our native forest such as Oplismenus aemulus, the Creeping Beard Grass or Ottochloa gracillima. These grasses can even be mown to create shade-loving lawns (see I can even use the L-A-W-N word in a positive sense).

So next time your strolling across your vast lawn ask yourself - do you really need all that grass? And next time your walking through or along the edge of you local forest don’t forget to appreciate all those wonderful small native plants at your feet – I just love dichotomy!

	Some fantastic native groundcover
	Pollia crispata – Pollia (left)
	Viola hederaceae - Native Violet (right)
	Oplismenus aemulus - Creeping Beard Grass
	Ottochloa gracillima – Ottochloa
	Lobelia trigonocaulis – Rainforest Lobelia
	Carex polyantha – Rainforest Carex
	Hydrocotyle pedicellosa – Money-wort
	And a whole range of ferns of course!

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To Weed or not to weed, that is the Question.
By Spencer Shaw

A year ago, on the Blackall Range we were treated to the sight of big flocks of Topknot Pigeons Lopholaimus antarcticus cruising around the skies. To witness these big groups of birds can be an inspiring sight for many. However when I mentioned that the large number of Topknot’s also coincided with a particularly good fruiting of the exotic camphor laurel’s Cinnamomum camphora the joy tends to evaporate and is replaced with a look of concern.

What a confusing situation! On one hand an inspiring, immense and beautiful flock of native birds. On the other hand we have an insidious, noxious and invasive weed tree. Unfortunately the two are quite firmly entwined in their lifecycles.

General consensus is we should be getting rid of all weeds, right? However, if we get rid of all the lantana, privet, tobacco and camphor, are we then depriving the native birds and animals that spread them - of habitat possibly crucial to their survival. It is often said that weeds are damaging the local ecology, invading native ecosystems and reducing biodiversity, but is this true of all weeds, in all situations?
The question I wish to pose is ‘can weeds actually increase biodiversity?’ I’m going to play the devils advocate here and say yes. What’s that I hear you say, he’s finally gone mad - perhaps spent a little too much time out in the sun or taste tested one too many funny looking mushrooms?

Weeds such as camphor laurel, privet and lantana are spreading in our local environment because of the relationship they have with our native fauna. Weeds most often thrive in disturbed ecosystems or ecosystems in a state of change. Mature rainforest is very stable and one of the most resilient of ecosystems to weed invasion. However areas that have been cleared of rainforest are highly susceptible to weed invasion. In an area like the Blackall Range we thus have the perfect conditions for weed establishment, large tracts of cleared land and the birds capable of spreading weed seed. Most remnant rainforest is highly fragmented in small patches throughout the range. Much less than 10% of the landscape on the red soil areas of the range is home to remnant rainforest ecosystems. These fragments are so small and isolated that many species will die out in these remnants, the areas are just too small to sustain them. However the spread of many weeds such as camphor, privet and lantana has created vital links between many forest fragments and also created buffers to protect the edges of remnants.

What we must remember when we view these weeds as a problem, is that the weeds didn’t arrive in this area independently of us, create wide scale ecological imbalance and then plant themselves. We created the situation and exotic plants are exploiting that situation. What’s left of the native fauna are also exploiting whatever resources are available - they certainly don’t pause to consider whether a fruit is of an exotic tree or not, they are just hungry!.

I’m not for one second suggesting that weeds don’t require management, I for one like nothing better than a good bit of lantana smashing or privet and camphor felling. But when undertaking these activities we should also be giving due consideration to habitat values for native wildlife?

In my particular reveg plot when we started 90+% of the habitat was exotic. We left the majority of the camphor laurels and planted the grassed areas. We also left 50% of the lantana patches but as the replacement habitat has developed from the planting’s, the exotic weeds are now being cut out or being out competed.

Thank goodness we now have projects such as the Corridors of Green projects and other reveg activities both private and public that are establishing corridors of native vegetation through planting or regen’. But also let’s not underestimate nature’s capacity to create its own corridors out of whatever is left available. The good news is that the more native vegetation we plant or regenerate the greater will be the future seed production of these species and maybe one day we will see as many native seedlings popping up as exotics

Solanum mauritianum fruit are a valuable food resource for birds such as Macropygia amboinensis the Brown Cuckoo-Dove.

Ligustrum lucidum fruit are a valuable food resource and corridor tree for many birds such as Satin Bowerbirds Ptilonorhynchus violaceus and Catbirds Ailuroedus crassirostris crassirostris *.

*If you think botanists have made the scientific names for plants complicated, then you will soon realise that zoologists have taken the art of complicated names to a whole new level.

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