Tuesday, June 20, 2017

Spectacular Tulipwoods
Harpullia pendula
It is worth the climb up tabletop at the moment, just to walk across it and look down the eastern side.

The tulipwoods are spectacularly in seed, about half-way down. Some of the trees seem be more fruit than leaf. It would be quite difficult to get down to them, so we didn’t, contenting ourselves with looking down on them and photographing them from a distance.

 The tulipwoods are spectacularly in seed, about half-way down. Some of the trees seem be more fruit than leaf. They are unusually late, as the showy fruits are more often seen in summer - although like so many native trees, they take advantage of rain when it happens. This display would be the result of the lateness of our summer rains this year.

The photos below (taken elsewhere) show how pretty the seeds are, with their showy pods that last on the tree long after the birds have taken the shiny black fruits.


The flowers are pretty little things, but far from showy.

Tulipwoods are fast-growing small trees, very commonly used as street trees in Brisbane where they are valued because of their non-invasive roots and their reliable tendency (when grown in the open) to remain below the height of power lines.

Popular in gardens, they make a nice patch of shade without growing too large. Birds love to nest in the dense foliage, and the trees can be butterfly hosts, as well.

They tolerate the light frost that is typical of the eastern side of Toowoomba.    

Tuesday, June 13, 2017

Frost Resistant Plants

Here are some potential good ones for Toowoomba and the Eastern Darling Downs.
(But note that there are no guarantees. For some reasons for this, see articles below the list.)
Best Species for  Heavy Frosts (over approx -7°C )

Large Trees
Araucaria bidwillii  BUNYA PINE
Casuarina cristata BELAH
Casuarina cunninghamiana RIVER SHE-OAK
Eucalyptus camaldulensis RIVER RED GUM
Eucalyptus eugenioides THIN LEAFED STRINGYBARK
Eucalyptus viminalis MANNA GUM

Medium Trees
Acacia deanei DEANE’S WATTLE
Acacia harpophylla BRIGALOW
Acacia implexa LIGHTWOOD (If seed of local provenance)
Acacia maidenii MAIDEN’S WATTLE
Acacia pendula WEEPING MYALL
Acacia stenophylla DALBY WATTLE
Callitris glaucophylla WHITE CYPRESS
Cupaniopsis parvifolia    SCRUB TUCKEROO (protect while small)
Eucalyptus conica FUZZY BOX
Geijera salicifolia    SCRUB WILGA
(protect while small)
 Melaleuca bracteata BLACK SHE-OAK
Melia azedarach WHITE CEDAR
Melicope micrococca. WHITE DOUGHWOOD
Pittosporum angustifolium GUMBY GUMBY

Small Trees
Acacia deanei DEANE’S WATTLE
Acacia hakeoides HAKEA WATTLE
Hymenosporum flavum    NATIVE FRANGIPANI

Bursaria spinosa SWEET BURSARIA
Denhamia bilocularis    HEDGE ORANGEBARK
Dodonaea triangularis TRIANGLE LEAF HOPBUSH
Eremophila maculata SPOTTED EMU BUSH
Hibbertia aspera ROUGH GUINEA FLOWER
Lomatia silaifolia    CRINKLE BUSH
Senna artemisioides subsp. zygophylla DESERT SENNA
Tasmannia insipida NATIVE PEPPER BUSH
Xanthorrhoea glauca GRASS TREE

Ground Cover
Eremophila debilis    DEVIL’S MARBLES
Dianella caerulea BLUE FLAX LILY
Dianella longifola LONG LEAFED FLAX LILY
Dianella revoluta BLACK ANTHER FLAX LILY

Rushes and Sedges
Lomandra longifolia LONG LEAFED MATRUSH
Carex appressa TALL SEDGE
Juncus usitatus PIN RUSH

Poa labillardierei TUSSOCK GRASS
Poa sieberiana SNOW GRASS
Themeda triandra KANGAROO GRASS

 Also all the grasses which grow naturally on our black soil plains.
Hardenbergia violacea PURPLE WANDERER

For Areas of Moderate Frosts (approx. -3°C to -5°C)
The above species, plus:
Large Trees
Araucaria cunninghamii HOOP PINE
Castanospermum australe BLACK BEAN
Corymbia intermedia PINK BLOODWOOD
Diploglottis australis NATIVE TAMARIND
Dysoxylum fraserianum ROSEWOOD
Eucalyptus biturbinata LARGE FRUITED GREY GUM
Eucalyptus microcorys TALLOWWOOD
Eucalyptus moluccana GUM TOPPED BOX
Eucalyptus pilularis BLACKBUTT
Eucalyptus tereticornis FOREST RED GUM
Euroschinus falcata RIBBONWOOD
Ficus rubiginosa SCRUB FIG

Medium Trees
Acacia irrorata GREEN WATTLE
Acacia melanoxylon BLACKWOOD
Allocasuarina luehmannii BULL OAK
Allocasuarina torulosa HILL SHE-OAK
Alphitonia excelsa SOAP TREE
Angophora floribunda ROUGH BARKED APPLEGUM
Aphananthe philippinensis NATIVE ELM
Auranticarpa rhombifolia GOLDEN HOLLYWOOD
Brachychiton acerifolius FLAME TREE
Brachychiton discolor LACEBARK
Brachychiton populneus KURRAJONG
Brachychiton rupestris BOTTLE TREE
Capparis mitchellii NATIVE CAPER
Cryptocarya glaucescens JACKWOOD
Cryptocarya triplinervis var. pubens HAIRY BROWN LAUREL
Elaeocarpus obovatus HARD QUANDONG
Eucalyptus melanophloia SILVER LEAVED IRONBARK
Eucalyptus melliodora YELLOW BOX
Eucalyptus populnea BIMBIL BOX
Flindersia collina LEOPARD ASH
Grevillea robusta SILKY OAK
Guioa semiglauca GUIOA
Mallotus philippensis RED KAMALA
Pittosporum undulatum SWEET  PITTOSPORUM

Small Trees
Acacia fimbriata  BRISBANE WATTLE
Acacia hakeoides HAKEA WATTLE
Acacia salicina WILLOW WATTLE
Acronychia oblongifolia WHITE ASPEN
Banksia integrifolia TREE BANKSIA
Croton insularis SILVER CROTON
Leptospermum polygalifolium TANTOON TEA TREE
Melaleuca quercina OAKEY BOTTLEBRUSH
Melaleuca viminalis (Callistemon viminalis) RED WEEPING BOTTLEBRUSH
Pittosporum viscidum BIRDS NEST BUSH
Psydrax buxifolia (Canthium buxifolium) BOX LEAFED CANTHIUM

Acacia decora PRETTY WATTLE
Acacia podalyriifolia QUEENSLAND SILVER WATTLE
Dodonaea triangularis TRIANGLE LEAF HOPBUSH
Dodonaea triquetra LARGE LEAF HOP BUSH
Hovea lanceolata LANCE LEAFED HOVEA
Hovea longipes BRUSH HOVEA
Indigofera australis NATIVE INDIGO
Jacksonia scoparia DOGWOOD
Carissa ovata KUNKERBERRY
Cassinia laevis COUGH BUSH
Dodonaea viscosa STICKY HOP BUSH
Maireana microphylla SMALL LEAFED BLUEBUSH
Pittosporum revolutum HAIRY PITTOSPORUM
Rhagodia parabolica FRAGRANT SALTBUSH
Rhagodia spinescens HEDGE SALTBUSH
Solanum aviculare KANGAROO APPLE

Alocasia brisbanensis CUNJEVOI
Doryanthes palmeri SPEAR LILY

Other flowering plants
Swainsona galegifolia DARLING PEA
Hardenbergia violacea HARDENBERGIA
Clematis glycinoides OLD MAN’S BEARD
Kennedia rubicunda RED KENNEDY PEA
Pandorea jasminoides WONGA VINE
Billardiera scandens APPLE DUMPLINGS
Hardenbergia violacea HARDENBERGIA
Hibbertia scandens SNAKE VINE
Pandorea pandorana WONGA VINE

Ground Covers
Atriplex semibaccata CREEPING SALTBUSH
Enchylaena tomentosa RUBY SALTBUSH
Small Flowering Plants
Chrysocephalum apiculatum YELLOW BUTTONS
Goodenia rotundifolia STAR GOODENIA
Scaevola albida FAIRY FAN FLOWER

Bulbine bulbosa BULBINE LILY
Microlaena stipoides WEEPING RICE GRASS
Rushes and Sedges
Schoenoplectus validus RIVER CLUBRUSH
Lomandra hystrix CREEK MATRUSH

Tolerates Light Frosts Only (to approx -2.5°C)
Large Trees
Argyrodendron actinophyllum BLACK BOOYONG
Eucalyptus saligna SYDNEY BLUE GUM
Ficus macrophylla MORETON BAY FIG
Flindersia australis CROWS ASH
Lophostemon confertus BRUSH BOX
Toona ciliata RED CEDAR

Medium Trees
Arytera divaricata COOGERA
Atalaya salicifolia SCRUB WHITEWOOD
Bursaria incana FROSTY BURSARIA
Citrus australis NATIVE ROUND LIME
Cupaniopsis parvifolia SCRUB TUCKEROO
Denhamia disperma ORANGE BOXWOOD
Denhamia pittosporoides VEINY DENHAMIA
Diospyros australis PLUM EBONY
Drypetes deplanchei YELLOW TULIPWOOD
Elattostachys xylocarpa WHITE BEETROOT TREE
Emmenosperma alphitoniodes YELLOW ASH
Flindersia xanthoxyla LONG JACK
Guioa semiglauca GUIOA
Glochidion ferdinandi CHEESE TREE
Gmelina leichhardtii WHITE BEECH
Myrsine variabilis MUTTONWOOD
Polyscias elegans CELERYWOOD   
Rhodosphaera rhodanthema DEEP YELLOWWOOD
Streblus brunonianus WHALEBONE TREE
Vitex lignum-vitae SATINWOOD

Small Trees
Alectryon tomentosus HAIRY BIRDS EYE
Backhousia angustfolia MYRTLE, CURRY
Gossia bidwillii PYTHON TREE
Psydrax species  CANTHIUM
Streblus pendulinus WHALEBONE TREE

Alchornea ilicifolia, HOLLY DOVEWOOD
Pittosporum revolutum HAIRY PITTOSPORUM
Trema tomentosa TREMA

Gardening with Frost:

Tips and Tricks
Creating a frost-wise garden is more than choosing the right plants.

1. Map your garden’s frost shelters in winter. (See article below) Even the coldest garden has places where the frost doesn’t form. A tiny frost-free niche is all a plant needs, to get started. You may find, with careful winter research, that your frost-free areas are really quite generous in size.

2.  Plan your spring plantings, based on making best use of existing frost shelters. You may save yourself a lot of work and cost, for an equally satisfying result, by making some small changes in just where you will put your first gardens.

3. Grow frost barriers. Get started on a frosty site by putting in tougher plants, and arrange them so that in the future they will create new areas of frost shelter. Consider creating quick canopy - even low shrubs may be enough to give you a site where trees can safely start their lives. Also consider how you can plant barriers to divert the downhill flow of frosty air away from your future planting sites. (Always consider where the diverted frost flow will end up, though.) With good planning, you will notice how your area of frost-free garden space grows every year.
(Note that temporary fences of shade-cloth can also operate as frost barriers. They are not as effective as plants, but may be just what you need.)

4. Plant as early in spring as possible, to get maximum growth happening before the next winter. Use whatever watering techniques are available, to get the plants well under way before the summer heat. Remember that intelligent use of water - using water crystals, getting the water down deep without wasting any on the top layer of soil - will produce quicker growth than merely throwing lots of water at the problem.

5. Don’t waste tree stumps.
Some plants which would die if planted at ground level can thrive if placed a metre or more off the ground in a stump. Both its height, and its insulation are helpful factors. Ficus rubiginosa (of local provenance) is a good, tough species to grow this way, and will make a big, bird-attracting, frost sheltering canopy. (It’s not for a small garden, though!)

6. Go easy on the winter weeding. A layer of small weeds of a rather non-competitive type (like chickweed) conserves a warmer air layer close to the roots of your small plants.

7. Go Easy in Winter Fertilising and Watering, too.
Avoid it completely, if you can. Healthy plants survive frost better, but plants with soft new growth are more susceptible to frost. This is why a late spring frost can do so much damage, when the plants survived the same cold temperatures happily all through winter. The time for watering and fertilising - if you need it at all, is the part of the year when there is no risk of frost.

8. Consider soil moisture. 
Light, dry soils get cold more quickly. If the soil freezes, it kills some roots. This effect is greatest on shallow roots, and therefore on smaller plants. Moist soil protects from frost to some degree as it keeps a more even temperature. So how do you manage to have damp soil, without springing the plants into dangerous growth? Well this is obviously tricky, with our dry winter climate. Preventing moisture loss with mulch is an obviously sensible technique. shade and the shelter of low plants can help, too. Even a little moderate watering, when there is no sign of a warm spell is usually not enough to cause out of season growth. Planting the toughest plants in the driest sites is also something to consider. In all, there's no easy answer to the problem of having just the right soil moisture.

9 Plan for suitable mulch.
Mulch can make frost worse, or help plants survive, depending on what it is made of, how damp it is, and how thick.  Some mulching materials (stones, sand, dry organic mulch) cool down faster than others, sucking warmth out of the nearby air and the surface soil and losing it to the frosty air. They can cause unnecessary losses to frosts. Slightly damp mulch, like slightly damp soil, has a protective effect.. A thick blanket of organic mulch is better than a thin one. It may frost on its dry surface, but keep the plant roots safe below in the moister lower layers, and the soil below.

10. Consider the Sun.
Frost reaches its coldest point just before the sun begins warming the surrounding air. Depending on their species, plants can tolerate a certain amount of freezing of their tissues if they warm up gently.  This can be why one of two apparently equal plants may suffer while the other one escapes. The one with more early morning shade isn’t damaged like its sun-warmed neighbour. Placing semi-hardy plants where they are sheltered from the early morning sun can sometimes be just enough to save them. Knowing this, you may be able to extend your planting our into currently frosty sections of garden.

11. Cover your plants before frosty weather. Or not, as the case may be. Don't take it for granted that you need to do this at all.  Clever planting and garden management might mean you never need to. However, if you want to use this technique, real security comes with three good stakes supporting metre-high hessian walls, and a flap to make a roof at night. (Make the flap sloping, so the frosty air runs off. Remember that plants need sunlight, too, though not necessarily every day in this dormant time of year.)
If you are prepared to take a chance, an ordinary, inexpensive plastic tree guard, with three bamboo stakes may be all the shelter your plant needs, until it has grown out its tender baby stage. A rather floppy job, with one low stake allowing the top to lean inwards, helps keep the coldest air out.

12. Run to the Rescue.
Despite all your careful planning you are assailed by sudden doubt! The night was clearer, and colder than you thought it would be. A frost is sure to follow. Will your plants survive?  Plants be saved in the early light of a frosty morning, by being watered with cold water from the tap before the sunlight hits them. Water in the plant tissues may be frozen by the frost. Some plant species can tolerate a certain amount of this, so long as they are melted gently. Tap water brings them up above freezing point before the sun gets a chance to warm them up at a damaging speed.

13. Predict the danger of a Sudden Cold Snap.
Plants which have been subjected to a series of increasingly cold nights slow their growth rate down, and so have less soft new growth to get damaged by frost. A sudden cold change catches plants unaware, with their fresh growth all vulnerable.  Watching weather predictions can help us to predict when extra care is needed.You may want to put temporary covers on if a spring cold snap is predicted - or simply plan to be out early with the hose, giving the foliage of susceptible plants a good wetting.

14. Consider commercially Available Frost Protection Sprays. These are claimed to work, letting plants survive temperatures as much as  4°C lower than they could normally cope with. (I have have considered - and rejected - them so have no experience with them. You may choose otherwise.) They are costly, so I imagine they would be most used to nurse precious little plants through their first season or two, rather than in any general way. As with so many commercial garden products, though, you will never really know whether your money was well spent. Perhaps the plants would have survived after all, without it!

15. Surviving BLACK frosts.
Those horrible sneaky things! They don’t happen often, but when they do, they are invisible. We feel so cheated when our plants begin to die, just when we thought we had escaped the frost.
Visible frosts  are made of frozen water. That's why they are white. There is usually at least some moisture in any air. It settles on the plants as the air gets colder overnight, and then turns white as it freezes. But if the air is very dry it can reach freezing temperature with no white frost to reveal its presence. What is worse, dry air freezes more quickly than moist air, so a night of the same overall temperature has a colder bottom layer. The moisture in the plants' leaves freezes, just as it would with a white frost, but we can't run to the rescue with a hose because we don't realize that it's happened. That's a "black" frost.
All the above management techniques work, though, just as they do with white frosts.

16. Take a few Risks.When in doubt, plant it. You have nothing to lose but some plants, and you might be delighted by your unexpected successes. Our local native plant species are relatively untried in garden situations, but are proving to be hardier than it was once thought.

“Frost Hardiness” Labelling 
   Why is it often unreliable? 

Labels and lists which state that certain plants are frost hardy certainly help us choose better. However we need to keep in mind that we may lose some plants that "should have been" hardy, according to the written information.

On the other side of the coin, many plants which can really cope with our local frosts are sold with “frost tender” written on their labels. Understandably, plant sellers would rather err on the side of caution to save themselves from being accused of leading people astray. This means that we might avoid planting many lovely plants which really could have grown perfectly well in the relatively mild frosts of our own climate. 

Predicting how plants will survive all kinds of frosts, in all situations, is an impossible task.

Here are some of the Variables:

The meaning of “Frost Hardy”.
Some people call a plant frost tender if it might suffer “frostburn” on just a few leaf-tips. Others consider that any plant that is not actually killed is frost hardy, even if all the above-ground parts of the plant are destroyed. Many plants are designed to to exactly this, and can survive very hard frosts. Partial death is their frost survival technique.
(Typical examples are deciduous trees, and the traditional herbaceous perennials of our European gardening tradition.)

Degree of Frost.
Some places have colder frost than others. A plant that is "frost hardy" in a typical Toowoomba frost (perhaps -1½°) might not survive a -8° frost at Oakey. Lists of supposedly frost hardy plants from a coastal source will include plants that would never be put on a list made up by someone from the granite belt. Knowing where the frost advice comes from can help us decide how a plant would cope with our own conditions.

Some plants are frost hardier than others of the same species. Just as with people, plants vary within the species. Ones whose parents grew in frosty areas are likely to better survivors than the apparently identical plants, whose ancestors had it soft. Try to get plants of local native provenance, and be aware that the “same” plant, selling in a commercial nursery, may not be quite the same, really. Your local plant may do better than the one the nursery has chosen to label "frost tender".

Plant Height vs Freezing Air Height.
We only actually notice frost when it lies white on the ground, or on the plants, but really it’s the cold air that is the “frost”. At the end of a night, the lowest air is the coldest. Frosts occur when that lowest layer is below freezing point. The height above the soil surface of this below-freezing temperature air varies. A showy white frost can form at the bottom of a layer of freezing air that is only ankle deep. In this case, the only plants to suffer serious damage are the little ones. On the other hand, if that layer of freezing air is two metres deep, plants can be damaged to the height of those two metres. The depth of the frost can vary considerable even in a small garden. Think of it as behaving like floodwaters. There are places where the cold air will make deep pools, and others where it will flow away quickly and never reach a great depth. This means that you might lose one of two identical plants, just because that one is situated in a spot where the frosty air gets deeper. It is difficult to create labels and lists that reflect this reality.

Age of Plant. 
In nature, baby trees and shrubs in frosty areas tend to establish themselves in small, sheltered micro-environments. A clump of grass uphill can be enough to do the trick, dividing the flow of frosty air, and leaving a small warm pocket in its lee. By the time they outgrow the shelter, the young trees’ deeper roots and higher canopies keep them out of the way of that ground layer of freezing air. but of course the crucial height varies from species to species. Labels and lists have a problem being accurate about at just what age which species can survive what degree of frost.

Your own management techniques.
No label or list can hope to be exactly accurate about all plants, in all conditions. How can a stranger know how dry your soil, how well you manage watering, what kind of mulch you use etc, etc.

Think of plant labelling as a guide to managing plants, not as a guarantee that plants will perform in your garden exactly as the label and list-makers expected.

Map your Frost in Winter

The biggest frosts follow clear wind-free nights. We can expect some good ones next week, as this rainy spell clears up.

Frost reaches its peak at that magical time when dawn has achieved full daylight, but no rays of sunlight have yet touched the ground.

That is when you need to be out there in your ugg boots and beanie (and perhaps some other garments in between, if you feel the need), to see just where it lies, and where it doesn't.

People who live in areas well-known for hard frosts are often surprised to find just how many frost-free patches there really are in their own gardens, (or on their larger properties). Mapping the frosts often reveals that we can grow many more frost tender plants than we thought we could. It can also mean that the cost and work of covering tender plants might not be really necessary.

If you carry a handful of stakes and a hammer, on your morning walk in the frost, you can mark frost-free spots where little plants will thrive. Plan your spring plantings as you go.

Frost flows downhill like a river. It is diverted by obstacles in its way, and it pools in hollows and above barriers. You may find quite large frost-free areas downhill from these barriers.

As well as this, every tree and shrub has a little frost free "aura" around it. It is smaller on the uphill side and larger below.  You might choose to plant under the tree, but note that the aura is larger than the its canopy. If root competition might be a concern, take advantage of the aura's outer edges.

Structures also have frost-free auras, though to a lesser extent.

While planning this year's spring plantings, you might also look for places to create frost shelters for the future. These can be rows of the frost-hardiest species. They can be as simple as a row of those tough matrushes, Lomandra longifolia, or a taller barrier perhaps doubling as a hedge, screen or windbreak. They are particularly efficient as frost-breaks if  they are bow-shaped and placed across the direction of frost flow with the centre of the bow uphill from the ends. This diverts the flow outwards, creating a sheltered nook to be filled with tender plants in a few years' time.

Forests and shrublands tend to hold the day’s warmth overnight. In our part of the world, ground temperature in these environments is always above freezing point and frost tender plants grow in them with no trouble at all. Restoring damaged ecosystems with their full range of original species can be a problem where clearing has thrown the area open to frost. A skeleton planting of pioneer plants to fill the clearing with a frost-free aura is a sensible first step. A serendipitous result can be that longer term species from the surrounding ecosystem don’t even need us to plant them. Changing the microclimate lets nature do the job for us.

With time and careful planning, it is possible to eliminate frost over large areas.

Sunday, June 11, 2017

Giant Stinging Tree

Dendrocnide excelsaFamily: URTICACEAE

Now Showing: The giant stinging trees are glamorously in fruit at the Bunya Mountains at the moment.

This wonderful tree pulls more than its own weight as a member of a rainforest community.

It is a fast-growing pioneer tree, quickly filling spaces in rainforests caused by falling trees or human interference, and making a good starter tree for revegetation work in frost free areas.

It grows to be one of the most magnificent tall trees in the forest, becoming part of its upper canopy.

It supports plenty of fruit eating in the winter, when other fruits might be harder to find, and no doubt provides them with insect protein at nesting time. You can see that insects just love the leaves!

These “fruits” look delicious, don’t they? Don’t EVER put any in your mouth. A few stinging hairs nestle in among them, as you can see in the photo below. I didn’t notice they were there, as I picked this small bunch for a close-up photo but can vouch for the fact that they were in good working order.  Ouch!  I found the sting much worse than the sting from a leaf. They could be very dangerous indeed if they stung the inside of your mouth or throat, so resist any temptation to sample the flavour!

Actually, these pretty things are not technically fruits at all, but the swollen stems of the little, dry pale brown seeds. The ones above are white because they are not yet ripe. They will get to be a rich, deep pink as they ripen, and the seeds will darken to biscuit brown. (double click on the photo to see a close-up) New trees can be grown from these seeds. The species is sometimes dioecious, so the plants you get from seed might be male, female, or a bit of each. Pure male trees won’t fruit, of course

The leaves look quite furry when the plants are young, but develop a shiny look when they get older. You might even wonder whether they are a different species.

Don’t be deceived! All the leaves have the stinging hairs, and do sting, even after they have fallen from the tree and look dead and dry.

Personal reactions vary.  I find that if I brush lightly against a leaf, the effect is no more than I would get from an ordinary nettle. However other adults have suffered severely with allergic reactions or anaphylactic shock, causing severe pain which recurs for years, and has had side effects such as temporary blindness. This is not a plant to mess with!

Stinging tree's timber is soft, and of no use for construction purposes. At the end of its life-span it breaks down rapidly, completing the cycle of growth, death and decay that provides food and habitat for so many species.


The leaves of young trees tend to be held horizontally, and are a particularly pretty part of the rainforest scene.

Stick something onto the sting. Rip it off, pulling the stinging hairs with it. Some bushwalkers always carry a bit of gaffer tape or cloth-backed duct tape, (for repairing broken boots in an emergency), and it works well on nettle stings, too. But it works best on stinging hairs that have not been touched, so try it FIRST, not last.

Friday, June 9, 2017

Mountain Katydid

Have you seen any of these?

A nice enough creature, but not really remarkable until it does this:

This is a female mountain katydid, Acripeza reticulata. The males have brown wings of a more normal kind, but the females are flightless. The only function of this lady's little wings is to cover up the pretty abdomen until she wants to frighten off a predator.

Mountain katydids used to be common in the Toowoomba district, but are not often seen nowadays, probably because of habitat destruction as our suburbs spread. They are know to feed on two local plants, the local Senecio species (yellow daisies).and the climbing Parsonsia species.

They absorb poisonous chemicals from the plants as they eat, which gives them a nasty smell - not particularly noticeable to human noses, but enough to discourage predators from eating them.

This insect's numbers have been declining and scientists would like to know where it can still be found. The best places to look are where there is plenty of the food plants. Can you please email me if you see one? (A photo would be good, and some details about exactly where it was found would be even better.)

Pretty Yellowtops

Senecio pinnatifolius var. pinnatifolius 
(Senecio lautus subsp dissectifolius)

Keep an eye out for these attractive local wildflowers, on roadsides and in paddocks. Short-lived perennials, they make very good garden plants. They grow easily from seed, and are worth it both for their colour, and their potential to attract butterflies.

They are  very frost and drought hardy, needing no watering once established, and flower from early spring to Autumn, with strong flushes in both those seasons. This would be an excellent waterwise species to use in our district as a bedding annual.

There are a number of Australian yellowtop species. This is the common one around Toowoomba. It’s an upright little perennial, about 30cm high and broad, with a slightly woody stem. It can be scraggly in dry paddocks, but in good garden soil has fairly dense mid-green foliage and makes a neat round shape. Most of its wispy leaves are very finely divided, to the point where no part of the leaf is more than about 1mm wide.

Do they Poison the Horses?

Many good native plants are less appreciated than they deserve, because they have an unfair reputation for deadliness to livestock.

Yes, all Senecio species do contain poisons, and eating too much of them will kill stock. However, the CSIRO book which is the best authority on the subject ("Australia's poisonous Plants, Fungi and Cyanobacteria" by Ross McKenzie) states that “no confirmed poisoning cases (by this Senecio species) are recorded in Australia” . There are two reasons. One is that no single plant contains much of the poison, and a bit of a munch does the animals no more harm than we suffer when we eat plants with similar poison levels such as mint, basil, or parsley. The other is that animals don’t like the taste, and won’t eat it if anything more palatable is available.

It is probable that most of the reports of “seneciosis” in Australia are old stories (which would be why they are not "confirmed") from the days when droving was common. Starving mobs would find themselves following routes that had already been used many times in the season. Previous mobs had eaten out everything worth eating. Deaths occurred. In fact, Senecios may or may not have been the actual cause of the problem, but are the ones most likely to be blamed just because they are so bright and conspicuous. The ability to diagnose just which plant was poisoning the stock has come a long way since then.

We see situations similar to those over-used old stock routes nowadays in  horse paddocks just west of Toowoomba, where overgrazing leaves nothing but the unpalatable and poisonous plants. With most of the competition removed, the paddocks can be taken over by wall-to-wall yellowtops. These are an indication of the owner's style of pasture management, not a sign that the yellowtops are poised to take over the world.  Fortunately, those horses are not depending on what grows in the ground for their feed. So long as they are well fed in other ways, the Senecio is not a danger to them because they really don't want to eat it.

In normal healthy local pasture, native yellowtops are dotted about amongst the other pasture plants. The photo above was taken on a local cattle property where livestock have grazed for more than a century and a half, apparently taking no harm from them.

But don’t Grow Madagascar Fireweed.
Senecio madagascariensis

This is a non-Australian plant that has become a major weed in Australia. It is just beginning to creep into our district from the east. It has been in the Lockyer valley for some time, and is now found in the Ravensbourne area.

Madagascar Fireweed is an aggressive coloniser, definitely a threat to stock because of its high level of invasiveness, and its tendency to out-compete native pasture plants. This could happen simply because it seeds more vigorously (up to six generations a year compared with one generation a year for our local Senecio species.)

Unfortunately, alarmist attitudes to all fireweeds can do more harm than good. Some landholders remove all of the local Senecios, just on principle.

Obviously care is needed with plants in yards or wherever alternative feed is not on offer, but otherwise it is probably best to leave the native plant in place. It saves unnecessary work and expense, and a side benefit is that property owners who are familiar with the local species will find it easy to pick the difference between it and the Madagascar fireweed, should an infestation occur. This difference is difficult to describe or show in a photo, but anyone seeing the interloper in the flesh would immediately notice that it is not their familiar plant. I just has a different look about it. A bit more upright. More of the leaves lance-shaped and only a minority deeply dissected (it’s strongly the other way round with the local Senecio pinnatifolius). Bigger seeds in those fluffy seedheads.

A further clue, if you are not sure, can be to count the involucral bracts. These are the long narrow green bits, pointy at one end (with a little brown dot on the point), which together form the involucre.

For me, essential equipment is: a pin (so I don’t lose my place); another pin (to point with); and a good pair of reading glasses. Senecio madagascariensis has 19-21 (usually 20-21) of these bracts. S. pinnatifolius var pinnatifolius usually has 13, though it sometimes has more. If the flowers on your plant have fewer than 19 bracts,  this confirms what you probably already knew from looking at the foliage - that it is the native species.

So. It's important not to grow Madagascar fireweed - but it's also important not to go overboard, exterminating perfectly good native plants on suspicion. Quite apart from being pretty wildflowers, an ornament to our landscape, they are also (like every component of any natural environment), an important part of the web of life. Some insects depend heavily upon them. Birds depend on the insects, and so on. We should never tear wantonly at the fabric of our local web.