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CALGAROO A journey into nature Newsletter of the Parramatta and Hills District Group Australian Plants Society NSW Ltd Our vision: inspiring people to admire, grow and conserve native plants
WHAT’S ON IN 2024
| 3 July Wednesday 10am: | Propagation |
| 13/14 July Weekend | Visit to Illawarra Grevillea Park, Bulli, plus other activities. |
| 14 August Wednesday 10am: | Propagation |
| 24 August Saturday | Visit to Crommelin Arboretum Pearl Beach |
| 11 September Wednesday 10am: | Propagation |
| 21 September Saturday | Visit to Fairfield Indigenous Flora Park (to be confirmed) |
| 9 October Wednesday 10am: | Propagation |
| 26 October Saturday | Bushwalk Lake Parramatta. Leader Jennifer Farrer |
| 6 November Wednesday 10am: | Propagation |
| 23 November Saturday | Members’ meeting and end-of-year celebration Gumnut Hall |
| 4 December Wednesday 10am: | Propagation |
If you’d like to come to our propagation days at Bidjiwong Community Nursery and haven’t been before, you can get details from Lesley Waite – phone 0438 628 483
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Weekend visit to Illawarra Grevillea Park Botanic Garden
When: July 13th and 14th, 2024
Where: Illawarra Grevillea Park Botanic Garden
Grevillea Park Road, Bulli, NSW (just behind the Bulli showground)
Our weekend away this year will be to the Illawarra Grevillea Park Botanic Garden. It’s only a short drive (about 1.5 hours) so if you can’t make it for the whole weekend, it’s an easy day trip.
Saturday 13th July: Meet at the Grevillea Park at 10am where we will start with morning tea and an introductory talk by Ray Brown OAM, Park Manager. Ray is the founder and driving force behind the ongoing development of the Grevillea Park.
Bring your own morning tea including hot water as there are no tea making or water heating facilities at the park. Following this we will spend the remainder of the day exploring the park and enjoying lunch with the group. Once again BYO lunch.
Entry fee to the park is $7 per person. They have a wide range of excellent plants for sale from tubestock to larger established plants. Lots of Grevilleas and Eremophilas, propagated from cuttings and grafted, along with a wide variety of other Australian plants.
If you are staying overnight in the region this link may be helpful in booking accommodation:
https://www.visitwollongong.com.au/accommodation/
Sunday 14th July: There will be one or two short walks during the morning in the Wollongong area followed by lunch (venue to be decided) before making our way home in the afternoon. We are planning to make the walk(s) as easy as possible so those with limited mobility can still participate.
Potential Sunday walks:
Puckey’s Estate Nature Reserve
Mt Keira Lookout
I’m told these both have short walking tracks and are easily accessible. There is a kiosk/café at Mt Keira Lookout so this may be a good place for our Sunday lunch.
Joan Hayes
History of Garden Design using Australian Natives
Jennifer Farrer
Our speaker at the June meeting was Stuart Read, a member of the Australian Garden History Society, who has worked for the Federal Government’s Biodiversity and Heritage units on projects such as National Heritage listings. He gave us a very comprehensive survey with very interesting illustrations of the use of Australian native plants since the time of European settlement.
Even before the actual settlement of Australia, interest had started in the biodiversity demonstrated in the plants brought back by Joseph Banks. Kew Gardens began growing Australian native plants in 1771 and selling them in 1774. Nurserymen such as the Kennedy Brothers were beginning to propagate plants and sell them from 1788.
Early settlers’ attitudes to the bush were very pragmatic. Some cleared all native plants to make way for crops, others were keen to learn from the local Indigenous people, particularly which plants were poisonous, or which could be used for food or fibre. Others enjoyed the beauty and diversity of the local flora.
The use of plants in garden design came later. Some of the earliest styles were in entrance avenues to homes such as Lieutenant Governor George Johnson’s at Annandale. Conifers such as Norfolk Island Pines and later on Bunya Pines and Sydney Blue Gums were favoured.
In Governor Macquarie’s time, the landscape style was the fashion for gardens. This can be seen in early sketches of Parramatta Park, elements of which are still retained today, and also of the original Government House in Bridge Street Sydney where Norfolk Pines, Casuarinas and Xanthorrhoeas featured.
Bunya Pines became very popular after their discovery in Queensland and were exported all over the world, in much the same way as the Wollemi Pine has been in the 21st century. Around Sydney, they were used as markers for homesteads.
At various stages in the 19th century, there were crazes for ferns and also palms. The Palm Grove at the Royal Botanic Gardens in Sydney dates from the 1880’s.
Public parks were invented in the 1850s. Many of these, such as the redesign of the Melbourne Botanic Gardens, reflected the new Gardenesque style which enabled families to stroll together along the new wider paths, featuring Australian plants. The Garden Palace for the Exhibition of 1879 located opposite the Mitchell Library is a Sydney example.
The new garden suburbs created in the early 20th century featured street trees to reduce dust from the traffic for the first time. In Melbourne, the first street trees were Eucalyptus globulus. These were later cut down and replaced by Elms. In Sydney, street trees were often Brush Box or Lilly Pillies.
Public gardens created in the early 20th century often featured Australian plants, reflecting the Nationalism which preceded and followed Federation Two examples from Melbourne were Maranoa Gardens 1901 and Wattle Park 1914. (Both fondly remembered from my childhood in Melbourne JF).
The spread of suburbs in the interwar period gave many people their first opportunity to have a garden of their own. Nurseries and gardening books appeared to help people plan these new gardens. Ferns and native orchids were often favoured.
In the 1930’s artists such as Margaret Preston and writers like May Gibbs featured native flowers. Architects such as Hardy Wilkinson, Oliver Dowell, Marion and Walter Burley Griffin popularised the use of native plants in their designs.
After World War II, garden designers such as Edna Walling, Ellis Stones, Paul Sorensen, Max Shelley, Bruce Mackenzie and the Maloney sisters brought new ideas for the use of native plants in gardens which led to the popularity of bush gardens in the 1970’s, which many members will remember.
Stuart left us with questions that will need to be resolved by garden designers in the future, including the need to respond to the challenges of climate change, the need to look after our soils and the responsible use of water.
Malcolm Johnston with an armful of wonderful native flowers – including grevilleas, banksias, acacias and paper daisies. And it’s wintertime too!
A fierce battle is being fought in the soil beneath our feet – and the implications for global warming are huge
Kristine Crous, Senior Lecturer, Hawkesbury Institute for the Environment, Western Sydney University
Belinda Medlyn, Distinguished Professor, Ecosystem Function and Integration, Western Sydney University
David S Ellsworth, Professor of Plant Eco-physiology, Western Sydney University
From The Conversation
As humanity continues to burn fossil fuels, the delicate balance of life on Earth is changing. That’s true of trees, many of which are growing faster as a result of increased carbon dioxide (CO₂) concentrations in our atmosphere.
But not all trees are responding in this way. In particular, eucalypts – Australia’s iconic forest trees – haven’t benefited from the increase in CO₂ as they were expected to. Why not? Our new research, published today in Nature, shows it comes down to a below-ground battle for phosphorus, a mineral nutrient in soils that is essential for tree growth. The results suggest in some parts of the world, increased CO₂ means tiny bugs in the soil “hold onto” their phosphorus, making less available for trees.
This is alarming news because according to current projections, global forest growth is meant to limit damage from global warming.
What our study involved
Our study used data from a Western Sydney University experiment known as “Eucalyptus Free Air CO₂ Enrichment”, or EucFACE. The experiment is located in a century-old Cumberland plain woodland in Sydney’s Hawkesbury district.
CO₂ is released into the woodland through a computer‐controlled system. Scientists then monitor the effects on trees, soils and the broader ecosystem. Over six years, CO₂ was raised to the levels expected around the year 2050 (according to the current business-as-usual emissions trajectory).
Our previous studies found the woodland trees did not show any extra growth at high CO₂ levels. We suspected the low availability of soil phosphorus was the cause, and set out to test this.
Phosphorus is crucial to the process of photosynthesis that makes trees grow. Phosphorus in soil is provided by bugs known as microbes. These micro-organisms break down dead and decaying matter, and in the process change phosphorus into a form that plants can take up with their roots.
Most Australian soils are naturally low in phosphorus, because they are derived from ancient, nutrient-depleted rocks. The same is true for most soils in tropical and subtropical regions. That makes the phosphorus service provided by microbes even more important.
We sampled phosphorus in all parts of the ecosystem, tracing its journey from the soil to the trees.
We found under high-CO₂ conditions the microbes keep more of the phosphorus they produce, to aid their own metabolism. This left less available for trees to take up. This occurred despite the trees trying to “bargain” for phosphorus by releasing extra carbon into the soil to feed the microbes.
What’s more, trees are big “recyclers” of phosphorus – they remove half of the phosphorus from any leaf before it falls. But this was still not enough to support extra tree growth.
EucFACE is designed to predict the effects of rapidly rising atmospheric carbon dioxide on Australia’s unique native forests.
Photo Sally Tsoutas
Why this matters
Our study is the first to show how the phosphorus cycle is affected by high CO₂ – and in particular, the role of soil microbes. The results are important for predicting soil phosphorus availability, and plant productivity, in woodlands and forests as CO₂ levels increase in the atmosphere.
Current climate projections assume increasing CO₂ will lead to more forest growth globally. Forests are a vital carbon “sink” – that is, they draw down carbon from the atmosphere. So, the increased forest growth was projected to go some way to limiting the effects of climate change.
If our results are taken into account, future warming would be higher than current projections. However, it’s important to verify our results in other locations, with other tree species. New experiments are being formed by overseas teams, including in the Amazon rainforest, to test the findings.
Importantly, our results don’t mean that forests are not a crucial sink for carbon. Forests hold a vast quantity of carbon. Avoiding deforestation and planting new forests are both valuable means of maintaining and adding to carbon stores. Our research demonstrates the importance of considering soils when growing trees. We also hope our research stimulates further efforts to find phosphorus in ecosystems, especially in tropical rainforests where phosphorus is often greatly limited.
Interesting Links . . .
Pampas: a weed on the rebound – from the Invasive Species Council.
Bringing new life to an ancient nut (Bunyas of course!) – from The University of Queensland.
Jane Goodall inspires generations of conservationists – we need her education program in schools – from The Conversation.
The bush preschool cultivating the next generation of nature lovers – from Springwood Local News.
The real natural history of our tall, wet forests – from Australian Geographic.
Only 10% of native plants can be bought as seed – a big problem for nature repair – from The Conversation.
The Woodland Trust is the largest woodland conservation charity in the UK and has planted over 50 million trees since 1972- from Wikipedia.
Why we know so little about Australia’s fungi – from The ABC.
From Botanic Gardens of Sydney under Creative Commons – NSW Department of Planning and Environment:-
Hardenbergia violacea
is hard to go past if you want to design a garden that’s colourful, low maintenance and fast-growing.
Image: The Botanic Gardens of Sydney
General planting and care
Hardenbergia violacea, Purple Coral Pea or False Sarsaparilla, is a climbing or prostrate plant found in many parts of Australia.
Several varieties have been developed for gardens including Flat White™ and Carpet Royale™, both in white and mauve. These are fast-growing, low-maintenance, heavy flowering, shallow-rooted plants with long trailing stems forming a dense mat, and unlike most other varieties of Hardenbergia, these can be used in a variety of positions in the garden as they do not climb.
Planting conditions
A full sun to part shade position is preferred in a wide range of soil types including light clay or sand, however, these cultivars will grow best in an enriched, well-drained acid soil on a raised bed with a pH of 5.5 to 6.0.
They possess a low frost tolerance when young and can sustain significant leaf damage but will become hardier with age.
Transplanting
We recommend that you do not transplant Hardenbergia violacea once established.
Irrigation
Avoid wetting Hardenbergia violacea’s foliage to minimise possible fungal problems. Monitor watering levels in the first season after planting and during the warmer months of the year to maintain adequate soil moisture.
Fertiliser
Fertilise with a general purpose three-to-four-month slow-release fertiliser in spring and autumn. Supplementary applications of a complete liquid fertiliser at two to three weekly intervals will assist with plant health and vigour.
A liquid feed of magnesium sulphate (Epsom Salts) and iron chelates in April will also assist in maintaining strong vigour before flowering, especially in sandy soils.
Mulching
After planting your Hardenbergia, we recommend mulching to a depth of 5 cm to conserve soil moisture and assist with plant health.
Pruning
For shrub forms, pruning after flowering will increase vigour and create a bushier plant with increased flowering in the following season.
Pests and diseases
Hardenbergia violacea is susceptible to powdery mildew during cool moist weather and should be monitored and treated with an appropriate organic fungicide, if necessary. Fungal problems can be minimised by avoiding foliage wetting during irrigation and by periodically removing dead leaves to improve air circulation.
Monitoring plants for evidence of leaf damage should be carried out to avoid major pest infestations, such as leaf-chewing caterpillars. Scale insects and mealy bugs can also become a problem in crowded situations.
“In every walk with nature, one receives far more than he seeks.”
. . . John Muir
There’s a Wattle
There’s one from Cootamundra,
and one out Mudgee way.
One from the Flinders Rangers,
from Gosford and from Hay.
There’s a silver one from Queensland,
and one where I belong.
There’s a wattle from the Snowy,
and there’s one from Wyalong.
There’s one I know called “Golden”,
and another one’s called “Black”.
There’s one from Wallangarra,
and along the Six-Foot Track.
Some grow as tall as gum trees;
some grow along the ground.
The leaves of some are soft to touch,
on others, spikes are found.
Some grow out in the mulga,
and some grow by the sea.
Some like the scorching desert,
or where the snows will be.
The emblem of the Great South Land:
Gold, in a hostile sun.
The wattle spreads across a land,
where time itself begun.
Brian Roach
July, 1997
Photo Lesley Waite
Slime Mould
From Wild Blue Mountains Facebook
This yellow, gelatinous, bubbly substance might at first glance appear to be some type of insect egg, but it’s actually one of the slime moulds that feed on the microorganisms found in any type of dead plant material.
Slime moulds contribute to the decomposition of dead vegetation, and feed on bacteria, yeasts, and fungi. For this reason, slime moulds are usually found in soil and on the forest floor.
Slime mould is an informal name given to several kinds of unrelated eukaryotic* organisms that can live freely as single cells but can aggregate together to form multicellular reproductive structures.
Slime moulds were formerly classified as fungi but are no longer considered part of that kingdom and are now referred to as belonging to the kingdom Protista.
More than 900 species of slime mould occur globally. Their common name refers to part of some of these organisms’ life cycles where they can appear as gelatinous ‘slime’. Most slime moulds are smaller than a few centimetres, but some species may reach sizes up to several square meters and masses of up to 20 kilograms.
A yellow slime mould seen recently on the forest floor at Blackheath. Photo: Teresa Sanchez
When food is abundant, slime moulds can exist as single-celled organisms. When food is in short supply, many of these single-celled organisms will congregate and start moving as a single body. In this state they are sensitive to airborne chemicals and can detect food sources.
They can readily change the shape and function of parts, and may form stalks that produce fruiting bodies, releasing countless spores, light enough to be carried on the wind or to hitch a ride on passing animals.
- Eukaryotes are organisms whose cells have a nucleus enclosed within a nuclear envelope
Some Memories of WA
Jennifer Farrer
For most of May this year we were on a trip to Western Australia. May is not the time of year to visit WA if you want to see the famous wildflowers. We went at that time to see the marine life at Ningaloo Reef including the famous whale sharks who come every year between April and July. However, the trip was not without some interesting plant life.
No trip to Perth is complete without a visit to Kings Park. Even in May, there were some spectacular flowers to see.
An endangered species of Mallee only known in five populations over a range of 3km in WA near the town of Eneabba.
found in sand dunes in the Shark Bay area of WA
Probably the most significant plant that has arrived in Kings Park since I last visited is the 750-year-old boab tree which was moved from the East Kimberley to Kings Park in 2008. The tree was in the way of a new bridge construction at Telegraph Creek near Warnum. The local Gija people gifted the tree to Kings Park and it was transported 3,200km over 6 days – The longest land journey of a tree this size in history. This story was told on Gardening Australia at the time.
Today it continues to thrive in its new location and will continue to do so hopefully for many more centuries.
Apart from Ningaloo Reef, the other focus of this trip was the Pilbara and the National Parks at Millstream and Karajini.
As there is always a wattle in flower every month of the year acacias were lighting up the understory.
Acacia hamersleyensis, as its name suggests, is found only in the Hamersley Ranges.
The most common tree in Karajini National Park is the Snappy Gum Eucalyptus leucophloia.
This month’s recipe:
Linda’s Bunya and white choc Lemon Myrtle biscuit
2 cups Bunya flour
½ cup sugar
2 teaspoons baking powder
2 eggs – beaten
1- 1.5 tablespoons lemon myrtle powder
150grams crushed white choc chips
½ to 2/3rd cup of vegetable oil
Mix all ingredients together and form into balls
Cook in a 160 deg. (fan forced) oven for approx. 8 minutes,
push down the mixture with a fork to flatten a little and then
back into the oven for another 8 minutes approx.
Let cool and enjoy!
Here’s the starting recipe that I changed:
Linda Pine
Share your stories . . .
Your contributions to Calgaroo are always welcome.
If you have interesting observations of plants in the garden or the bush, photos, or any other news, please send them to me at itcox@bigpond.com for the next edition.
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In the spirit of reconciliation, we acknowledge the Traditional Custodians of our Country, the people of the Dharug Nation, whose cultures and customs have nurtured, and continue to nurture, this land since time immemorial. We honour and celebrate the spiritual, cultural and customary connections of Traditional Owners to Country and the biodiversity that forms part of that Country.
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Parramatta and Hills District Group
SECRETARY: Jennifer Farrer apsparrahills@gmail.com 0407 456 577
EDITOR: Ian Cox itcox@bigpond.com