Thursday, December 31, 2009

Irongate Nature Conservation Reserve

This delightful reserve, between Pittsworth and Mt Tyson, will be well worth a visit over the next weeks, as it is springing to life with the rain we've been having.


These resurrection ferns (Cheilanthes distans) would have been so shrivelled, a few weeks ago, that they would have been hard to spot. Already they’ve turned into lush green things that wouldn’t look out of place in a rainforest.








Not everything will be as quick to produce new leaf, but we can expect plenty of it there in the coming weeks, as well as a number of plants putting out fresh flushes of flowers.


Across the road from the reserve is this specimen of Silver Croton, Croton insularis, in the most spectacular state of flower that I’ve ever seen from this plant. Don’t miss it!




(For more about crotons see this blog July 2009)









Irongate Reserve is an interesting example of our district’s driest type of “rainforest”. It is so far from the usual conception of rainforest that the name “ dry vine thicket” certainly suits it better - yet the plants belong in the rainforest plant spectrum.
They are from its dry and drought-hardy end, and are plants which should find their way into our “waterwise” gardens. They are all tougher than prickly pear, yet can look very lush and pretty in easier environments than Irongate offers.
An added virtue, from the point of view of responsible gardening, is that they lack the serious weed potential of some of the exotics - particularly cactus, aloes, and agaves that have we have been seeing promoted in nurseries, TV shows and magazines as a waterwise “answer” to climate-change induced drought. They are making depressingly quick progress from the glowing magazine articles to the environmental weed lists.

TO GET TO IRONGATE CONSERVATION RESERVE:
(The route is all on bitumen.)
Go to Mt Tyson, (35 mins from Toowoomba, out Hursley Road).
Head west out the main street. After the property called Adora Downs the road makes a right-angled turn to the left (south). Follow this until it hits a T-intersection. Turn left, and note the Irongate Hall on the left. Turn right (south) almost immediately after the hall, and follow the road for something like 3.5k until you come across the reserve on your right. Keep your eye out for the iron gate that marks the place. There is a toilet and picnic table.
For more about it, follow this link:
http://irongatereserve.blogspot.com/
(And this blog June 2008)

Brush Hovea

Hovea longipes
Famiily: FABACEAE
I have been trying to catch this plant in flower for ages, and am surprised to have found it (at Irongate Nature Conservation Reserve) at this time of year.
Most Hoveas flower, magnificently, in late winter. This one is said to flower from March to September, though I have not actually seen it myself.
I now wonder whether it is a very flexible opportunist, able to take advantage of rain, whenever it occurs, to try for a successful crop of seeds - as do so many of the plants of the inland. Perhaps the rather modest number of flowers was also normal.
I would love to grow this plant. It is regarded as being so different from other hoveas that some botanists would like to see it reclassified under a new name. The flowers are blue, rather than the usual hovea purple, and the seedpods are a different shape.
It is a particularly attractive plant, even when not flowering - a large, rounded shrub, between 2 and 3 metres tall, and with a more substantial trunk than we usually expect in a hovea. Cattle pruned examples suggest that in a garden it could be persuaded with the secateurs to become a dense shrub. I suspect it of being longer-lived than other hoveas.

Native Daffodil

Calostemma luteum
Family: AMARYLLIDACEAE
The native daffodils began to come into flower just before Christmas. Unlike the introduced bulbs, all our local native bulbs flower in summer rather than in spring.
These plants are daffodil-yellow, but in form they are more like scentless jonquils. It’s something of a puzzle as to why they are not grown more often in Australian gardens, as they are very attractive plants.
Not all the flowers open at once, so you don’t get a good flower for vase use, as you do with jonquils - you do get a longer flowering time per head. For a good display in the garden, quite a few bulbs are needed.
The flowers are followed by shiny green bulbils, which drop off and germinate on the soil surface if they find a damp and shady niche. Otherwise, they need a little help from a friend. In two years, they develop large bulbs which pull themselves down about 20cm under the soil, and then proceed to flower for many years, dying down every winter, and reappearing in early summer.
They are only moderately drought hardy. Young plants need quite frequent watering in their first year of life. Mature bulbs are hardier, but for best results they need a good soaking in November, and another one or two as the flowers die down and the leaves feed their nutrients back into the bulbs.

(There is also a pink Calostemma, which grows naturally in western NSW, north-western Victoria, and South Australia. It is sometimes classified as a variety of C. luteum, and sometimes as a separate species, C. purpureum. Its flowers don’t open as widely as those of our local yellow one, but it’s a pretty thing nonetheless, and a more drought-hardy plant than our local.)

Thursday, December 10, 2009

Weeping Bottlebrush

Callistemon viminalis (Melaleuca viminalis)
Family: MYRTACEAE
This widespread Australian native is one of our only two locally indigenous Callistemon species. It has a graceful shape and long flowering season, and is much used in local gardens and streets. As with all callistemons, its flowers attract honeyeating birds, and butterflies.
The natural habitat of these small trees is in watercourses, on all kinds of soil. They would once have been very common in all along the creeklines of the district, including those in inner-city Toowoomba, where they would have grown with black tea-trees (Melaleuca bracteata), river she-oaks (Casuarina cunninghamiana), and an assortment of rainforest trees, shrubs, and vines.

We still see many of them in creeks along the range, but they have been largely cleared from the red and black soils west of it.

The early white settlers gave particular attention to clearing the vegetation in our creek-beds. In the early days, it was because scrub-covered watercourses provided cover where aborigines could hide, and provided them with routes along which they could travel inconspicuously, and from which occasional attacks on white settlers were launched.
Later, it was done because of a belief that vegetation in creeks impeded the water flow, making floods worse.
What a pity that this ruthless clearing drove our local platypuses to extinction!
Early attempts at revegetation, once the value of trees in preventing erosion was recognised, was done with willows, because of their quick growth as well as the widely held belief that they were more beautiful than any native plant. Unfortunately, willows exclude low-growing vegetation under their canopies so effectively that the soil under them is poorly defended from scouring by floods.
Modern revegetation efforts in creeks use natives, including this species.
Despite their natural preference for a creek habitat, weeping bottlebrushes have proven to be very hardy trees in situations where they can be quite challenged for water. They are widely used as street trees in Crows Nest (photo at right), and are a favourite front-yard tree on smaller suburban blocks in Toowoomba.
There, they may be the only remaining plant of a “native” garden of the kind which was popular in the seventies. Most of the plants chosen tended to be short-lived species, which have now lived their life-spans and are only memories.
Fortunately, the weeping bottlebrushes are relatively long-lived and continue to grace many Toowoomba gardens.

Thursday, December 3, 2009

Ivorywood

Siphonodon australis
Family: CELASTRACEAE
The ivorywoods in Franke Scrub, Cawdor, are still flowering at present, even though some of the fruits are already ripe. These pretty trees are also called “wild guavas”. Their beautifully aromatic fruit is edible. The Franke scrub ones are rather small and dry as we've had little rain, but the fruits on well-watered trees can be 5cm diameter. The flesh smells beautiful and tastes good - something between an apricot and an apple in flavour - but it is unpleasantly gritty.
Ivorywoods have the capacity to be canopy trees, with a trunk diameter as much as 45cm, in their natural habitat which is the moist and dry rainforests of northern New South Wales and southern Queensland.
They are rarely seen approaching this size nowadays. They were much cut for their fine, straight-grained timber, which is good for turning, carving, inlays, marquetry, and making engraving blocks. Modern turners and carvers seek it out - but cannot often find it now.
No doubt many of the older trees, which produce good residential hollows for wildlife, were also cleared to make way for “better” trees, as part of the typical strategy in forests which are managed for timber.
Unfortunately, these very long-lived trees are slow-growing, so the large old trees which have vanished may take several centuries to replace.
Once established, ivorywoods are drought tolerant, and hardy to light frosts. They
prefer to spend their early lives in shade, so are good plants to establish in the shelter of shrubs. There, where they are in nobody’s way, they would be hardly noticed for years. By the time they are becoming pretty small trees, with dense canopies of dark -green, shiny leaves, the shorter-lived plants will be getting to the end of their lives.
If we are to leave something of our gardens for future generations, we should all be planting some of these slow-growers.

Thursday, November 26, 2009

Now Flowering in Ravensbourne

Here are three plants whose fruits we notice more often than their flowers. A walk along the lower track at Ravensbourne National Park takes them all in.

Blue ginger Alpinea caerulea



There are a lot of buds on the plants beside the track, so they’ll make a pretty show for some time yet.
Though not as showy as the flowers of exotic gingers, they are pretty little things. They will be followed by showy electric-blue fruits around May next year.

(See entry May 2009 for photo of some of the last crop of fruit.)






Palm Lilies Cordyline petiolaris



The long-lasting bright red fruits are more often seen than these more ephemeral flowers. These beauties are right beside the main walking track, this week.













(See post July 7, for more on this plant)



Black Bean Castanospermum australe
This is one of the dominant trees of the dry rainforest in Ravensbourne National Park. The flowers are everywhere this year, so we can expect a great crop of the giant chestnut-coloured seeds about next Easter. The trees can flower while still quite young, with the flowers sprouting from old wood. Gardeners shouldn’t get too enthusiastic about pruning these plants, as they could accidentally remove future crops of flowers.
On older trees, the flowers tend to be hidden within the canopy. Our attention is often drawn to them by the clamour of nectar-eating birds.
Grown in the open, black beans trees typically become well-shaped specimens, with a dense canopy of shiny, dark-green leaves. (See the tree on the right, in this photo).




They are ideal for gardens which have room for a medium-sized tree, and make an excellent background plant for large gardens.
I noticed recently that the nursery in the Ikea shop in Brisbane was selling “magic beans”. These were pots with newly sprouted black bean seeds sitting on the soil surface. Very ornamental! Young trees can be used as indoor plants, in well-lit situations, for a number of years.
Black beans are toxic, but not really a family problem, as their seeds are not a size which an innocent toddler could easily swallow. Aborigines, whose diet tended to be low in carbohydrates that could be had from them, did eat these starchy things after a long process involved crushing and soaking them in many changes of water to remove the poisons. Modern bushfood-experimenters have tried it. Reports of the results vary. Some have made themselves very ill. All agree that the taste is so boring it’s not worth the trouble, especially when flour is cheap in the shops, safe, and tastes much the same.
The trees were rigorously exterminated from our area by the early white settlers, who believed them to be also toxic to cattle. Some also claimed that it was the size of the beans rather than the toxins which were the problem. Cattle, they said, swallowed them whole, then were unable to regurgitate them for cud-chewing. Intestinal blockages were the result.
I accepted the idea that black bean trees and cows don’t mix until told otherwise by a dairy farmer who had lived all his eighty years on the same property. This contained many of them dotted about the paddocks as shade for the stock, and cattle ate the seeds freely, he told me. He had never had any problems.
He had recently begun to discourage them, but only because he’d found a market for the seeds in Japan, where they were being used to develop a medicine to combat AIDS.
The dark streaky black bean timber is beautiful, and the trees are plantation-grown in the US as well as here. This is a great tree to grow on a “boutique” timber plantation.
Typical dry rainforest trees, they are drought hardy, and tolerate light frosts. They are quite fast-growing, which is why they dominate parts of Ravensbourne National Park. This park was logged with bulldozers in the thirties, so much of what we see there is still in the relatively early stages of progression to mature rainforest. Slower-growing trees will come later.

Thursday, November 19, 2009

The Best Butterfly Host

Native Caper
Capparis arborea
Family: CAPPARACEAE

If we all had a native caper of some kind - one of the Capparis species - in our gardens, we would never (except for a brief period in winter) be without butterflies.
Five local species of butterfly can only breed on caper trees, which are also called bumble trees, for their large, edible lumpy round fruits.

Two of them are pretty butterflies marked in black and yellow; the Caper White (Belenois java teutonica, previously Anaphaeis java teutonica) and the Caper Gull (Cepora perimale scyllara).
The caper white (right) is one of our most common butterfly species. It is a strong flyer, able to travel hundreds of kilometres. In some years enormous numbers of them fly over and through Queensland, delighting butterfly lovers, and providing food for many thousands of nesting birds.






The other three are rather undistinguished: the Chalk White (Elodina parthia) (at left); the Common Pearl White (Elodina angulipennis); the Narrow-winged pearl white (Elodina padusa). These can be a little difficult to tell at a glance from the feral cabbage white butterfly which is the most common white butterfly seen in our gardens.



In the bush, a concentration of fluttering white butterflies draws our attention to the presence of a caper tree. Having one in a garden would ensure that butterflies were present the whole season long, their fluttering hordes (and the birds they attract) being as much an ornament to the garden as the plant itself.
This native caper is in flower in Franke Scrub at the moment. It’s worth a visit, just to smell the strong, sweet perfume of the flowers. Each flower lasts only a day, but the tree still has hundreds of yet unopened buds so will continue to delight for some weeks.
Look for it on the northern edge of the scrub, close to the road. (You can see it easily from your car). It is a good specimen of this small tree species, showing the typical dense, shady canopy.
Capparis is a prickly genus. Tiny plants are very prickly indeed, with a pair of thorns at the base of each leaf. As adults, they lose the prickly habit to a certain extent, but if you examine the Franke Scrub caper tree you will still find traces of those paired thorns, which help to identify the tree.





There are lots of chrysalises on the Franke Scrub caper tree, and some evidence that caterpillars have been at work. I took this particular chrysalis home to see what would hatch out.












And here is the result.










(For more on native capers, see articles Sep09 and Dec08)
For directions to Franke Scrub, see article, Sep 09

Thursday, November 12, 2009

Bat’s Wing Coral Tree

Erythrina numerosa
Family: FABACEAE

Now is the time to get out to Prince Henry Drive, to see this glorious tree in flower. It’s really excelling itself this year.

This is also a great opportunity for birdwatchers to see the smaller honeyeaters which flock to the flowers.

If you’re like me, you’ll want to wear your bushwalking boots and get out three times along the route for a little walk down the slope, to appreciate this beautiful plant to the maximum.

If you're not into stopping and walking, do at least get someone else to drive you, so you have time to look across the hillside and appreciate just how many hundreds of these trees grow in this area. They tend to be inconspicuous until this time of the year, when they drop their leaves and blossom profusely.


The “batwing” leaves vary in shape according to the age of the trees, with those on young trees being particularly ornamental.





These coral trees grow naturally in and on the edges of dry rainforest. Their presence all over these slopes tells us that this environment was once extensive there.
There are few large trees in the area. Normally, we would expect to see them with diameters of up to 80cm, in the gullies and more sheltered places, but no doubt the fires which occasionally ravage the area keep them under control
Bat’s wing coral trees are easy to grow, provided they can be protected from frost in their early years. They also need to be protected from hares, wallabies, cattle, camels, etc, until their edible leaves and twigs reach a safe height.
Not everyone loves them, because of their prickles. The trunks of young plants, bristle with very sharp ones (which they need because so many animals find them tasty). I have found it worthwhile to go over the trunks of the trees in my garden with manicure clippers, to create something a bit more hand-friendly and child-safe.
As the trees age, the bark tends to grow over the prickles, and old trees have smooth trunks. Removing the tips does mean that they disappear all the sooner.


The soft timber was regarded as valuable by aborigines, who used it for coolamons and shields. Coral tree shields were also used as a base, when making fire with the friction method. European settlers used it for floats for fishing nets, polo balls, and brake blocks for horse and bullock-drawn vehicles.
The very hard orange seeds have a long history of use for jewellery.

Our Escarpment’s Vegetation

Before white settlement, the vegetation along the escarpment of the Great Dividing Range in the Toowoomba area would have looked very different.
It would have consisted largely of dry rainforest, with pockets and lines of dense moist rainforest in the gullies and stream beds. Both kinds of rainforest were described by the settlers as “scrub”, a term still often used for the drier types of rainforest vegetation.
There were plenty of permanent waterholes, such as the large one, still being marked on late 19th century maps, below Prince Henry Drive. There are still people who can remember swimming, on hot summers’ days, in the pool at the base of Highfields Falls.
Eucalypt grassland would have been restricted to ridgetops, probably existing in a more or less pure form only on those ridges which were traditional aboriginal travelling routes. Aborigines all over Australia regularly “cleaned up” such routes, by burning. White explorers followed them, because the going was easier, and these ancient travelways have since become our modern roads and highways.
It is worth noting that aboriginal use of fire normally resulted in only small areas being burned at a time. Most of it was done to improve the food-producing ability of the land, where the aim was to create a mosaic pattern of fire recovery areas of different ages. This gave them the maximum variety of foods.
One result was what they called a “clean” landscape, which wouldn’t carry a fire for long distances. Another was that areas of fire-sensitive plants such as rainforest and scrub species were not swept away, as they are nowadays by the runaway bushfires which are the result of post-European fire management - or the lack of it.
The process of wholesale clearing the escarpment’s rainforests and scrubs began in the earliest days of white settlement, when aborigines set extensive fires in attempts to get rid of the first invaders.
Timbergetters arrived with the squatters, felling rainforest trees at first, then turning to the eucalypts. Toowoomba’s early industries - a boiling-down works which produced tallow, and a fellmongery, as well as the steam sawmills which were soon introduced - used much of the “scrap” timber for fuel.
Settlers cleared as much of the “scrub” as they could, because they feared the aborigines who hid in it. They paid particular attention to exterminating small bunya trees, as bunyas were known to “attract” aborigines.
In the late nineteenth century the escarpment near Toowoomba was subdivided into tiny farms, mostly taken up by Irish settlers, who were energetic about clearing the land and keeping it clear, both manually and with fire. The result was the development of the current fire ecology, dominated by eucalypts and wattles, which invaded former rainforest territory. These fast-growing trees created the modern impression that our current fire-prone escarpment vegetation is the natural environment there.
The ease with which privet grows, wherever fire fails to keep the ground clear, tells another story.
Meanwhile the original waterholes and streams have largely dried up. Some of this has been from silting, as clearing exposed the soil. Some resulted from the change in groundwater levels which always results from the clearing of hilltop trees. Drought has an effect, of course, but it has been exacerbated by pumping from bores. Originally the greatest effect came from those used for market gardens, but recently the enormous increase in domestic bores in our suburbs, used largely for watering gardens, has had an effect, with the escarpment streams drying up or being reduced to trickles. This is most easily seen in the huge change to Highfields Falls in recent years. Only 15 years ago I saw a large eel in the pool where now there is only a circle of dry kikuyu grass.
That praiseworthy group, the Friends of the Escarpment Parks, has worked very hard to restore some of our original environment. In this they were supported and aided by the Toowoomba City Council, and perhaps the new council is being as helpful.... There are also private landholders doing wonderful work of a similar kind.
It’s hard to say, though, which is having most effect - the brave efforts at restoration, or the continuing destruction of our original landscape.

Friday, November 6, 2009

Black Jezabel

(Delias nigrina)


He does look painted, doesn’t he? The funny thing is, for a female Jezabel, the glamorous side of this butterfly is not these beautiful undersides to his wings, but the pure white wingtops, which he flashes when he flies.


The grey-topped females find the white very appealing!
With their wings folded, you can’t tell the boys from the girls.
This one, which flew into our garden last week, was looking for a mate.
He would have done better to hang around the bushland, as the girls don’t get too far from the plants where they lay their eggs.
Little caterpillars of every butterfly species can only survive on the correct host plants, and for the glamorous jezabels, mistletoes are it.
They are fairly broad-minded. Any mistletoe from the Loranthaceae family will do.
A good reason for growing one in your garden.

Do Mistletoes Kill Trees?

The definitive answer seems to be a simple “no”.
That they do is certainly a fondly-held belief in some quarters. We have seen it raise its head again with the current debate about the trees lining “Cathedral Drive” at Hampton. One writer to a newspaper has expressed the opinion that the trees might as well be killed, because they’re “infested” with mistletoe.
True, the trees are going to die one day. So am I, but I hope nobody uses this as a reason why I “might as well” be killed at once.
The trees are not going to die from mistletoe infestation, however.
Mistletoes don’t poison trees. Nothing passes from the mistletoe to the tree.
Variable mistletoe Amyema congener.  
 Family: LORANTHACEAE
This plant is growing on a boonaree (Alectryon diversifolium) in Franke Scrub.
 





This tolerant mistletoe grows on many different host shrubs and trees, including introduced ones like oleanders and crepe myrtles. Some local native hosts are Auranticarpa rhombifolia, Geijera salicifolia, lillypillies and callistemons.

Mistletoes are only partially parasitic. They make their own food, by photosynthesis, just like any other green plant.
What they take from their hosts is water. The amount they take does exceed what any other little branch on the same tree is taking, as Mistletoe leaves lose slightly more water than the tree’s own leaves - but there’s not much in it. A very small tree carrying a big mistletoe will have its growth rate slowed down, but the effect on a large tree is negligible.
Mistletoes are accused of killing branches, and this is true of some mistletoe species. They hijack the branch, preventing water from travelling past the point of the mistletoe's attachment. Branches killed are usually only very small at the time the "hijack" occurs, and the mistletoe replaces any small gap thus created in the canopy, with its own foliage.

Lucas’s Mistletoe
Amyema lucasii

This is a mistletoe which only grows on Flindersias, such as crows ash and leopard ash. This specimen was also in Franke Scrub.


Mistletoes are relatively short-lived plants. Trees can outlive generations of them. Some of the mistletoe skeletons we see on old dead trees would be of plants which died before the tree did, and only became obvious when the tree itself came to the end of its life, shedding its concealing canopy.
Trees under moisture stress have the ability to restrict their water loss to some extent by restricting the flow to their outer branches. This also kills off any mistletoes which were living there, so a drought-stressed tree actually has the ability to rid itself of some of its passengers.






Russet Mistletoe, Amyema miquellii restricts itself to Eucalypts.
A well-grown plant is 2m tall, so needs a large host tree.







Mistletoe “infestation” meanwhile can be a bit of an illusion. Mistletoes are forest edge plants, so we see a lot of them along roadsides, where humans have created long strips of their natural "edge" habitat. Only a few metres into the surrounding bush, the mistletoe population is always much smaller.
A lone tree, left in a paddock is a special case. Left in isolation after clearing, it becomes a “forest edge” all of its own and attracts the mistletoe birds which replant as they feed. It only takes 20 minutes for a mistletoe berry to pass through their little systems and for the seed to be deposited on a handy branch. The birds tend to spend longer in isolated trees before moving on, so these trees do get more than their fair share of mistletoe seeds.
Meanwhile, these lone trees in paddocks, often the source of the “mistletoes kill trees” myth, are already doing it tough.







Detail: Russet Mistletoe, Amyema miquellii. This highly ornamental mistletoe has red flowers, but its showy red spring leaves are an even more showy feature.






There are two reasons why paddock trees seem to die at a higher than normal rate.
One is that livestock collect under them in the heat of the day, and compact the soil with their hooves. Australia has no native hoofed animals. Livestock create a hard soil, unnaturally low in microorganisms - NOT a healthy environment for the poor trees' roots. In addition, stock crowded under trees add high levels of fertilisers to the soil. This is particularly hard on native trees which are adapted to Australia's relatively infertile soils. Even non-natives, quite unblessed by mistletoes, can be killed by excessive fertilising of the sort that paddock trees are subjected to.
A second reason is that some farmers, when they cleared, left the large trees for stock shelter but have never made any provision for their replacement as the trees die of old age. This happening at an increasing rate now, more than a century after the original clearing was done. No tree will live forever!
While it is possible that sick and dying trees are less able to fight off mistletoes so carry a heavier than natural burden, it’s a bit tough to blame the mistletoes for the death of these mistreated, elderly, paddock trees.
So we should stop blaming the mistletoes, and relax and enjoy them instead. They are beautiful plants in their own right, and deserve to be planted in mature gardens for their ornamental qualities as well as their environmental ones.



Brush Mistletoe, Amylotheca dictyophleba
 Family: LORANTHACEAE

This one grows on introduced trees as well as a variety of natives. We commonly see it around Toowoomba in winter, where is revealed on the London plane trees as they lose their leaves. It gives these trees no trouble, and provides a good source of fruit for native birds.





At least 41 species of native Australian birds are known to feed on mistletoe fruits. Honeyeaters visit them for their nectar. And a great many small bird species nest in their dense foliage. These are great bird-attracting plants!
There are also some beautiful butterflies which are disappearing from our suburbs because they can only breed on mistletoes. We need more of them!
If you’re worried that a too vigorous mistletoe might damage the tree that is the pride of your garden (though it probably won’t) you can prune it just like any other plant. Reducing its size will give the tree a chance to recover if indeed it was feeling the stress.
(Note: the particular mistletoe species shown here are members of the Loranthaceae family. The majority of Australian  mistletoes belong to this old Gondwanan family, and are characterised by their showy flowers and edible fruits.)

Thursday, November 5, 2009

Grow your own Thatch

Phragmites australis
(Phragmites communis)
Family: POACEAE
This is the plant you need, if you want to thatch your roof with a long-lasting home-grown product.










These plants are growing in the pond at Peacehaven Botanic Park at Highfields.









“Common reed” is a cosmopolitan plant, native to many areas of the world including Australia and Britain, where it is known as “Norfolk Reed”. (The name “australis” is Latin for “southern” - not “Australian” as Australians sometimes believe.)
In Europe, the plant is grown in specially cultivated reed beds, to supply the thatching industry. For good thatch, the whole crop should be cut each year, so that next year’s crop contains no dead reeds. A roof of these reeds can be expected to last for 50 or 60 years.
Thatch roofs have never caught on in Australia, though. Perhaps the bushfire hazard is a little too obvious!
Common reed is used around the world for making all sorts of things, from mats, baskets, and hut walls, to pens and arrow shafts. Its pretty purplish-brown plume-like seed heads are valued by florists.
In Australia, it is a “bush tucker” plant. The fresh root-tips (rhizome-tips, really) are produced in spring, and said to have a delicious flavour, like asparagus. They can be cooked in much the same way.
Not a true reed, this is actually a species of grass, but it grows in water like a reed. Others might suggest that it grows like a weed. It is certainly a very vigorous plant. With its strongly spreading rhizomes, it can easily fill a dam or pond.
It does have very high value as a refuge and nesting site for wildlife, and is grazed by stock. It can prevent erosion, tolerate salinity, grow in water or mud, and thrive in water as acid as pH5.5, or as alkaline as 8.7. Its only demands are full sun and enough water.
It is suitable for use in a planted wetland for purification of greywater, urban run-off, or even sewage waste. (For these purposes, it needs to be harvested annually. Pollutants are removed with the stems, and new growth takes up further pollutants as the plants regrow.)
Cutting below water-level in autumn kills the plant back, a useful technique where control is needed. If vigorous growth is what you want, it should be cut in back spring

Thursday, October 22, 2009

Sandpaper Fig

Ficus coronata
Family: MORACEAE
Figs are plants with very strange habits. Their flowers form INSIDE the young fruiting bodies, and are pollinated by wasps which enter by the tiny hole in the end. The “fruits” we eat may still be flowering inside. And yes, the wasps are always there. They're minute and fig-flavoured, so we never even notice that we are eating them.












This two-year-old  Ficus coronata in Peacehaven Botanic Park has put out a great old crop of fruit. You can see that it’s almost leafless. The species drops most or all of its leaves in early spring. (The leafless, fruiting branches do make a decorative feature in a flower arrangement.)

Ficus coronata also has the strange habit called “cauliflory”, where fruits pop straight out of the large branches and even the trunks, as in this photo I took a few weeks ago in the Brisbane Botanic Gardens.
(I have heard a rumour that Grapetree Road, near Pechey, was named for a plant with the cauliflorous habit. Does anyone know what the “grapetree” was? Please leave me a comment, below, if you do.)
This is the best native fig for garden purposes. Unlike the rainforest giants, the little sandpaper figs don’t have those enormous water-seeking roots (though it is still best to plant them five metres away from your pipes, paths, and foundations).
It makes a bushy little tree if grown in the sun. If it does get straggly, it’s easy enough to prune to shape, and can be kept to large-shrub-size.
Although these plants are most often found in creek beds in the wild, they are drought hardy trees which grow well (like specimen below) in unwatered local gardens.


















Plants can be dioecious (separate male and female trees) or monoecious (male and female flowers on the same tree), so to be sure of getting fruits, it is best to plant several of them. They can be planted close together, (40-50cm apart) to save space. After Christmas, the fruits ripen to this pretty shade of red.
All native figs are valuable food sources for birds, fruit bats, and possums. People also eat them, and those of Ficus coronata are said to be the best-tasting Australian fig.
Eaten raw , they have an quite acceptable flavour, though they can be a bit dry if they come from a drought-stressed tree. Rub the hairs off before putting them in your mouth! The fruits can also be used in cooking, or crystallised.
They are rather variable from crop to crop, even on the same tree, so if one lot is disappointing, have faith! Watering well as the trees are fruiting, and fertilising early in spring, are two ways to improve the crop.
And yes, you really can use the leaves as fine sandpaper!

Thursday, October 15, 2009

Native Frangipani

Hymenosporum flavum
Family: PITTOSPORACEAE
This is a very familiar small tree in local gardens, being one of the few natives that have “crossed over” into mainstream gardening.
It’s a small tree, no relation at all to the chunky-stemmed introduced "Frangipani" (Plumeria species) - but its flowers have a similar strong fragrance. As you will notice from the plant's family name, this tree is really a kind of Pittosporum.The family is worth exploring for other species, if you're looking for fragrant shrubs or small trees for a garden.
These flowers are unusual, with their flecks of red. I photographed them a few weeks ago while bushwalking north-east of Crows Nest.






The more usual flower is creamy-white when new, and ages to deep yellow, like those on this two-year-old specimen in Peacehaven Botanic park.
Well-watered specimens tend to grow fast, but need pruning to prevent legginess, while specimens that have "done it tough" bush up attractively without further attention. Grown in full sun they make a well-shaped ornamental tree. In the shade between buildings, they make a tall slender trunk with no branches, and the narrow crown peeping just above roof height.
They are claimed to be somewhat fire-retardant, so are a good choice for gardens where this might be a worry.

Thursday, October 8, 2009

Black Orchid

Cymbidium canaliculatum
Family: ORCHIDACEAE
Bushwalkers always find something to delight them. This magnificent black orchid was flowering its heart out in a dead ironbark tree last week. No doubt the tree had a big long hollow, which accommodated the plant’s enormous root system. More roots, had clearly formed since the tree’s death, as they were between the timber and the bark. The bark was peeling off, so the orchid will have to retrench a little when it goes.
I hope the orchid goes on in good health for many years though. There are good reasons for leaving hollow dead trees where they stand. The feather glider, which popped out while we were admiring the orchid, is another.
Ironbark timber is so strong that a dead one can stand for hundred years or more, still doing its bit for the ecology.
This lovely plant is Australia’s most drought-hardy orchid, and is common in the bush in our district. It‘s a plant of the inland, unusual in preferring to grow well away from the rainforests and vine scrubs which are the preferred habitat of most orchids.
It usually grows in hollow eucalypt trees, where the rhizomes ramble through the dark tunnels and rotten heartwood, and pop out leaves wherever opportunities arise. “Plants” which seem far apart - like the three in a Eucalyptus tereticornis not far from this specimen - may well all be part of the same plant. A large old specimen can have roots 10 metres long.
The name “canaliculatum” refers to the channel-shaped leaves, which direct rainwater and dew towards centre of the plant. This is part of the secret of the plant's drought hardiness. The other part is the huge root system, protected from dehydration in its well-insulated, deep tunnels. Orchids are usually regarded as acid-loving plants, so the discovery that the ends of the roots of big, old plants like this are actually in very alkaline conditions (pH 9!) is somewhat startling.
Black orchids often grow in exposed places well away from the shelter of any trees, and have even been known to establish themselves in fence posts. They are said to prefer a north-east aspect, but are certainly seen thriving in other positions.
Orchid enthusiasts from our coastal cities regard this as a rather difficult orchid to grow. It is uncomfortable in the humidity. We have an advantage over our coastal friends there, but it is very rare indeed to see a cultivated specimen as magnificent as this. It’s difficult to give it the conditions it really prefers!
These orchids - like many other of our native orchids - are easily killed by root disturbance, so trying to take an established plant like this home is most likely to kill it. Orchid “collecting” is usually just another name for vandalism - and of course, taking plants from the wild is illegal, unethical, and much resented by bushwalkers and other genuine lovers of Australia’s wild plants.

Native Bluebells

Wahlenbergia (stricta?)
Family: CAMPANULACEAE
Here is a lovely stand of native bluebells, which I photographed last week in “Glenvale Gardens”, a retirement village in Toowoomba. Apparently the garden won a prize in the Carnival of Flowers, and I’m not surprised at that.
The surprise was that locally native flowers were used in a local flower garden - something I’d love to see more often.
I didn’t ask, but I expect the flowers were Wahlenbergia stricta (white backs on the bells).


It is a common plant of our grasslands, often seen on our road verges around here where it takes advantage of the rainfall runoff provided by the road. It’s a perennial, which dies back in winter, to reappear in full beauty in spring.
Individual plants are rather sparse, so they are shown off at their sky-blue best if they are grouped, as these ones are. These are frost hardy, drought-hardy plants, which like to be in full sun.
I just wish they were easier to buy. If they were, I’m sure we’d see more of them on our local gardens.

Thursday, October 1, 2009

Peacehaven Botanic Park.

I went wandering in this park again this week, and had the pleasure of running into Robert Campbell (Toowoomba Regional Council, Parks and Gardens Highfields), who is responsible for the planting and maintenance of this remarkable botanic garden.







AXEHANDLEWOOD
Aphananthe philippensis

A dense plant which might prove to be good for hedging.









I found out that the park is younger than I thought, with these local native trees being only two years olds I am very impressed!
Robert tells me they have not been watered since they were planted. He credits the fast growth to the large hole which he digs for each one. (I gathered, from the general hand-waving, that these holes were about a metre across, and something approaching the same depth.) He scatters some slow release native fertiliser in with the soil as it is replaced, puts on a deep layer of course forest mulch, and the results speak for themselves!









GLOSSY ACRONYCHIA
Acronychia laevis

An ornamental plant with unusual blue and pink fruits







A garden full of plants of local provenance is something that hasn’t been done here before. We Toowoomba people are so used to having access only to “native” plants which have been brought in from elsewhere. Plants from local sources are now available, but haven’t made much impact, yet, on the local gardening scene. Robert did point out to me that much of the credit for Peacehaven’s ability to display this special range of plants is due to Steve Plant, (Natural Resource Management Field Officer TRC Northern Region) who has done some groundbreaking work in establishing the community nursery at Crows Nest. There, Steve grows local plants from local seed, and this is what Robert is growing at Peacehaven.


HAIRY LOLLY-BUSH
Clerodendrum tomentosum
A plant that stands out twice a year. In spring it has these perfumed flowers, then in summer it has very ornamental fruits.


It is really quite exciting to have something, in our own district, which is following the grand old tradition of botanic gardens - doing useful work in trialling plants. Our great Australian botanic gardens were established, like their overseas counterparts, to trial exotic plants. Their successes have become the staples of traditional Australian gardening.




These neat, permanent plant labels were sponsored by individuals and community groups, in a project organised by the Friends of Peacehaven, a group which meets there on Thursday mornings.








Meanwhile, Australian plants were being trialled overseas with enthusiasm, beginning when Captain Cook’s voyage arrived home with its collection of specimens. Much of our initial knowledge about how to grow our own natives was discovered overseas. Successful eucalyptus oil, and cut flower industries using Australian species, were established in faraway countries as a result of research done there. Australian plants were used in gardens in Britain and Europe long before they became popular here.








MOWBULLUN WHITEWOOD
Elaeocarpus kirtonii
A tree from the Bunya Mountains











As a nation we have recently come the full circle, with our modern botanic gardens trialling Australian plants for use in Australian gardens.
And now, in our own district, we have a place where we can see our own local native plants in a public garden setting, all neatly labelled so we know just what we’re looking at.
They do impress! These are clearly good garden plants.
How to find Peacehaven: If coming from Toowoomba, turn left at the first Highfields traffic light, into Cawdor Road. Take the third turn on the right, into Kuhl’s Road. (Stan Kuhl was the man whose general bequest of the land, to Crows Nest Shire Council, made the park possible.) Peacehaven Botanic Park is on the left, just a little way along.

Bitterbark Tree

Alstonia constricta
Family: APOCYNACEAE

If you’re quick, you’ll be able to catch this tree while it’s still in flower at Peacehaven Botanic Park, Highfields. The flowers have a very unusual musty sweet smell.

This is an unusually large specimen, retained from what must once have been a significant area of semi-evergreen vine thicket (dry rainforest) on the Peacehaven site. Nowadays, we usually see bitterbarks as slender little trees or shrubs, able to be picked out from a distance by their attractive white trunks. If damaged, they have a tendency to sucker and produce thickets (or hedges).

this is a fast-growing, drought hardy species, with garden potential, but rarely used.


This is one of those rainforest plants - some of them only found in dry rainforest ecosystems like those which once covered much of our local land - which may suddenly find itself highly valued in the future because of its potential to provide the pharmaceutical industry with a new drug.
Its white latex has been used to lower blood pressure, and some Alstonia species are also showing potential as a source of cancer cures.

Our early settlers would add the bark as a “bitter” to their medicinal concoctions and drinks, but I don’t recommend it! (There’s too fine a line between medicines and poisons.)
However, you might like to experiment with the bark for dye-making. A related species is used for this purpose in India. (Expect yellow.)

Thursday, September 24, 2009

Scrambling Capers at Franke Scrub

Capparis sarmentosa
Family: CAPPARACEAE


These prickly little climbers are having an unusually good flowering season this year. Lots of plants are in flower, and there are still plenty of buds to go, so they should continue to look beautiful for some weeks.


The plants are quite unpleasantly prickly, and their long-term future is by no means secure. This is not a plant that gardeners are likely to save from extinction by planting it in their gardens, despite its beauty.
Orphan plants like this remind us how important it is to preserve what scraps are left of their natural environment.
Scrambling capers are plants of semi-evergreen vine thickets on red soil, and would once have been very common in the Toowoomba district. Franke Scrub is one of the rare remaining examples of this ecosystem type, which (in its redsoil form) is classified as endangered.
There are several other local species of native caper (see article Dec08 for more about the others).
Two of them grow in Franke Scrub, as well, and are likely to flower soon too.

If you haven’t yet been out to see Franke Scrub, next Wednesday (30 Sep) would be a good time. Members of the Friends of Franke Scrub will be there in the morning, working away. See article below for directions to get to this spot, which is just 3 minutes from central Highfields - which is only 10 or 15 minutes from central Toowoomba.

Donkey Orchids

Diuris sulphurea
Family: ORCHIDACEAE


Wouldn’t you love to have a crop of these little fellows coming up in your orchard every spring? My neighbour found them last year while she was mowing, and only just missed chopping their heads off! They are there again, in the same spot, this year.

They are such a good reason for keeping a rough lawn of native grasses. Alas, that pesky weed, kikuyu, would have destroyed many such colonies, which grow naturally in the snuffy red soil along the range.



(Click on photos for a closer look)
North of Toowoomba, this habitat is being rapidly overtaken by acreage gardens such as this one. I do hope the householders are noticing the terrestrial orchids where they occur. Too much mowing would have destroyed this patch’s flowers before they had time to open.

Colony-forming ground orchids like these grow from little tubers, and multiply each year. The tubers were once eaten by aborigines, whose diet was rather low in starch, so they valued even such a small contribution as these donkey orchids could provide. Early white settlers ate them too - but fortunately, nowadays, we have more reliable sources of calories, and don’t need to eat our beautiful native flowers!







There are many species of donkey orchids (also known as “doubletails”), but this species is one of the most common, and can be distinguished by the two brown spots on the upper “petal”.







While ground orchids are considered more difficult to grow than the epiphytes, the donkey orchids are among the easiest of them. Growing them does, however, involve looking after a pot - or a patch of ground - which has nothing to show for most of the year. (Growers rarely do grow terrestrial orchids in the ground, but it should be possible to reintroduce this species to our gardens where they once grew naturally.)
In spring, however, each tuber puts up a few small leaves, followed by a single spike of flowers. It is usual for growers to put a number of tubers in each pot, to make an attractive display.