Small Talk Autumn 2017

In this issue

Managing acid soils – New tools are now available to help tackle acidic soil on your property

Making the Inman River catchment – The Inman catchment took leisurely shape over 2 billion years. Then humans arrived... 

Case study: Sustainable winegrowing in the McLaren Vale wine region and beyond – Improving sustainable viticulture practices, fruit quality and financial viability

Walking on sunshine with Katrina and Landcare – Meet Katrina Hewitt, our new Regional Landcare Facilitator

Pests - Keep an eye out for these unwelcome critters

Events – Find out what landholder events are planned for this autumn

Handy hint – Polypipe and vine guard recycling – Sustaining Endeavour provides a recycling and rebate service to growers in McLaren Vale, Langhorne Creek and Barossa regions

Things to do autumn – Get your property ready for the autumn season

Managing acid soils

Brett Masters, Soil and Land Management Consultant, PIRSA Rural Solutions SA, and

Chris Nichols, Sustainable Agriculture Officer, Adelaide and Central Hills, Natural Resources Adelaide and Mt Lofty Ranges

Small Talk PIRSA pH mapper

PIRSA pH mapper. Photo: Brian Hughes, PIRSA

New tools are now available to help landholders tackle soils acidity on their properties.

Soil acidity affects about 1.9 million hectares (20%) of agricultural land. It is the second highest priority threat (after soil erosion) to the sustainable management of agricultural soils in South Australia.

Untreated highly acid soils:

  • reduce growth and production of most agricultural plants
  • increase soil salinity due to increased drainage of rainfall to groundwater
  • increase leaching of iron, aluminium and some nutrients leading to contamination of surface and ground water
  • lead to structural breakdown of the soil

Measuring soil acidity 

Soil acidity is measured in pH units which show the concentration of hydrogen ions in the soil solution. The lower the pH, the greater the acidity. The logarithmic scale of pH from 1 to 14 has neutral at 7. A soil with pH 4 is 10 times more acid than a soil with pH 5 and 100 times more acid than soil with pH 6.

Many soils in higher rainfall areas of the state are naturally acidic, and sandy textured soils are at the highest risk of acidification.

Soil acidification can be significantly accelerated by agricultural practices including removal of grain, hay and livestock products from the paddock, use of ammonium-containing or ammonium-forming fertilisers, and leaching of nitrate nitrogen derived from legume plants or fertilisers. 

Higher levels of production also tend to lead to higher acidification rates. 

Small Talk summary of acidification rates

Small Talk influence management pie chart

Small Talk lime maintenance rate

New Excel tools

Three new Excel tools, developed by Primary Industries and Regions SA (PIRSA) consultants, allow farmers and consultants to compare costs of lime sources, calculate liming rates, and estimate the cost of lost production from soil acidity. 

Lime Cheque – compares the cost of liming with different liming products. Lime quality (neutralising value) information is used to calculate the rate and total tonnage of lime required on up to four different pH zones in a paddock. The distance from the lime sources (freight cost) and lime spreading costs are factored in to calculate the total cost of each liming operation. 

Maintenance Lime Rate Calculator – estimates soil acidification rates for a paddock by using soil texture, rainfall, crop rotation, product removal and fertiliser inputs to model the replacement lime required to offset acidification on a paddock resulting from agricultural production. 

Acid$Cost – uses soil pH information and crop rotations to estimate the financial cost ($ lost) over time because of soil acidity and can show how the cost of treating acidity is justifiable. 

Landholders can now more cost effectively address soil acidity on their properties with these tools combined with PIRSA’s new Veris pH and EC mapper (MSP-3). The mapper, with an experienced operator from Rural Solutions SA, is available for hire to measure and map the spatial variation of pH and EC on farms, vineyards or horticultural blocks. Such information allows the landholder to apply the right rate of lime in the right areas of the paddock. 

Access the tools

The Excel tools are available for download from the Ag Excellence Alliance website.

This page also hosts a range of resources for managing soil acidity in South Australia.

For more information on the tools, or the pH mapper please contact:

Andrew Harding
PIRSA Clare Office
Phone: 08 8842 6231 or 0417 886 835

The Department of Environment, Water and Natural Resources, Australian Government and Grains Research and Development Corporation funded production of these tools. 

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Making the Inman River catchment

RP Bourman and AR Milnes, visiting research fellows, The University of Adelaide

Small Talk perched swamp

Perched swamp, developed below the level of the deeply weathered summit surface. Photo: RP Bourman

The Inman Valley catchment is the home of grazing, dairy, forestry and horticultural enterprises, and picturesque scenery.

How did it turn out that way?

It all began more than 2 billion years ago with earth movements and climatic impacts.

The oldest rocks in the northern boundary of the Inman catchment are remnants from the original 2 billion year old core of the region.

The hard rocks forming the floor and sides of the catchment were created from heat, pressure and folding applied to sediments about 500 million years ago. These processes formed a huge mountain range of Himalayan proportions, since so severely eroded that the granites at the base of the mountain range have been exposed and today form headlands and islands in Encounter Bay.

Today’s Inman catchment was set up in Permian times with movements of an ancient ice mass up to 2 km thick, around 300 million years ago when Australia and Antarctica were still joined. Weathering and erosion since that time have formed the current features of the river catchment.

After the Permian ice sheets retreated, prolonged weathering and erosion created a mixture of low lying areas and more uplifted localities such as the high plateau surface on the margins of the catchment, exemplified at Spring Mount.

Several sea flooding events over the last 40 million years, after Australia and Antarctica separated, deposited limestone with evidence of a large number of marine fossils. They can be found at high levels in areas such as Myponga.

The last major sea level fluctuations since 125,000 years ago, produced river terraces and shorelines in the lower parts of the Inman River. Then, over the last 11,500 years, alluvial sediments have accumulated in channel bottoms forming floodplains and swamps.

The Inman catchment took leisurely shape over 2 billion years.

Then humans arrived and change accelerated

Small Talk James Track

Road cut on James Track exposing part of the iron mottled weathered zone beneath the high-level Spring Mount surface. Photo: RP Bourman

Over many thousands of years Aboriginal occupants actively managed the landscape, particularly through the use of fire. Plants and animals adapted to the mosaic-burning regime, which produced open parkland environments in places.

These landscapes were very attractive to the first European settlers in the early 1840s but the practices implemented to establish settlements supported by agriculture, even on a small scale, affected the landscape’s ‘equilibrium’. Clearing vegetation, stopping burning practices, ploughing single-furrow, and introducing livestock, rabbits and weeds, all triggered significant changes.

In less than 200 years, the landscapes adapted and generated new landforms. Some obvious signs of change are soil nutrient depletion, various forms of erosion (slumping, gullying, stream incision, stream bank collapse) and changes to where clay, silt, sand or gravel are deposited in waterways. The hydrology and water quality of the catchment changed.

Stabilising and healing the landscape

The last few decades have seen progressive changes in landuse, current land management strategies focused on soil and land conservation, erosion repair through revegetation and watercourse controls, and management of feral animals and plants. Agricultural landuse has adapted from the European settlement practices that triggered landscape changes to a system that is progressively stabilising and ‘healing’.

We investigated the geological basis of the catchment and recent historic impacts that have created the current landforms of the catchment, in a project initiated by the Inman River Catchment Landcare Group, funded through the National Landcare Programme and supported by the City of Victor Harbor.

Our report on the project draws on this long history and baseline information to examine management of current threats and identify management practices that will continue to improve water and soil quality of the Inman Valley Catchment.

See the full report, The geology and landforms of the Inman River catchment.

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Case study: Sustainable winegrowing in the McLaren Vale wine region and beyond

Jeff Edwards, Sustainable Agriculture Officer, Fleurieu and Willunga Basin, NR AMLR, and

Susan Ivory, Commonwealth Reporting Officer, NR AMLR

Small Talk Barossa grape growers

Barossa wine grape growers head down to the creek line as Sellicks Hill to view McLaren Wale’s community revegetation efforts.
Photo: Barossa Grape & Wine Association, Dragan Radocaj.

Landholders  McLaren Vale Grape and Wine Tourism Association, Friends of Willunga Basin, McLaren Vale Biodiversity Working Group 
Property location McLaren Vale region, SA
Average property size 23 ha
Current enterprise  Grape and wine
Average annual rainfall 650-700 mm

Sustainability benefits the environment but it also has broader benefits for the winegrowing industry and the wider community.

McLaren Vale Grape and Wine Tourism Association (MVGWTA) recognises these benefits and initiated the Sustainable Australia Winegrowing program to help winegrowers develop their sustainability credentials.

The program aims to give McLaren Vale grape growers a structured approach to improve sustainable viticulture practices, fruit quality and financial viability.

‘I think sustainability is holistic,’ said former Sustainability Officer at MVGWTA, and local viticulturist Dr Irina Santiago-Brown.

‘It’s about everything, from the consumer, who wants to drink high quality wine at a reasonable price. It’s about the farmer who needs to continue producing. It’s about the little shop that’s selling the wine.’

Sustainability is holistic

Small Talk biodiversity group

McLaren Vale Biodiversity Group leader Jock Harvey (far right) explains community restoration efforts on Sellicks Hill creek line. Photo: Barossa Grape & Wine Association, Dragan Radocaj

In 2014, Natural Resources AMLR partnered with MVGWTA to provide technical support in developing the Sustainable Australia Winegrowing training and education package, and tools for growers to self-assess against a number of key sustainability indicators.

Data capture and reporting through the program give growers a management tool to demonstrate their performance against their regional peers and recognise best practice. In the first year after initial roll out of the program, sustainable practices improved by 9.1% in vineyards in the McLaren Vale region.

Seeing its value to both the environment and the community, NR AMLR continues to support MVGWTA to expand the Sustainable Australia Winegrowing program. In 2015, a second course was run for a wider audience, and more than 40 people attended each of the workshops and seminars.

Because of the program, individual winegrowers are now working with NR AMLR on many other environmental and community-based opportunities, such as gaining technical advice through one-on-one site visits. NR AMLR is also supporting a range of targeted projects linked to three year work plans.

Biodiversity in the vineyard benefits us all

Small Talk restoration of native plants

Restoration of native plants at Chapels Hill’s Peter Creek line. Photo: Barossa Grape & Wine Association, Dragan Radocaj

The community has driven the formation of McLaren Vale Biodiversity Group, a grassroots group that includes a broad range of industry and non-industry community members, the City of Onkaparinga and Friends of Willunga Basin.

Supported by NR AMLR, the biodiversity group is proposing that vineyards trade biodiversity work and in-kind labour (where on-vineyard biodiversity work is not available) to improve their biodiversity score as part of the Sustainable Australia Winegrowing program.

Geoff Hayter, a passionate local grower and member of the Friends of Willunga Basin said, ‘the level of biodiversity reflects the health of our landscape’.

‘Biodiversity in the vineyard brings benefits through a healthier growing environment, ultimately resulting in better fruit being delivered to the district's wineries.’

The Sustainable Australia Winegrowing program is now accessible to other wine regions across Australia with the Barossa wine growing region the latest region to show interest. 

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Walking on sunshine with Katrina and Landcare

Small Talk Katrina Hewitt

Katrina Hewitt

Katrina Hewitt began 2017 as the Regional Landcare Facilitator for Natural Resources Adelaide and Mount Lofty Ranges, a move from the arid rangelands of South Australia based in Port Augusta. Working with staff from the Land, Marine and Biodiversity branch, located at the Cleland office, is both a sea and a tree change for the desert dweller.

Originally from the arid rangelands of Western New South Wales, Katrina grew up in the pastoral sheep and cattle industry, experiencing the highs of the wool market floor price and lows of the millennium drought as well as the removal of the wool market floor price.

Katrina moved into the urban environment of Broken Hill where she developed skills and experience in community and registered club management, business tourism and events management, presenting for the ABC rural report and regulating mining impacts.

It's a pleasure to meet you!

For the last ten years, Katrina has been developing a diverse range of skills in natural resources management and sustainable agricultural production working with local community individuals and land manager groups, representing regional catchment authorities and local land services. Her experience in agriculture was broadened to include viticulture, horticulture and dry land cropping.

Over those years, Katrina enjoyed studying to build the technical skills that support her working environment, obtaining diplomas in Rural Business Administration and

International Business and Marketing as well as a Bachelor in Ecological Agriculture and more recently, a Masters in Business Administration.

With a curiosity about how things work, Katrina is excited by the potential of working in this diverse region in a position that supports and facilitates knowledge and skill development.

Katrina is continuing Lucy Hyde’s activities, engaging with community, farming and Landcare groups that have a focus on sustainable agriculture. She is looking forward to meeting and working with regional community and industry members.

Please do not hesitate to contact Katrina with any questions about the AMLR Sustainable Agriculture Program, Landcare Program, or any other events and programs being supported in the region.

Katrina Hewitt - Regional Landcare Facilitator

Phone: 0408 678 890

AMLR Region
Southern Lofty Office
Summit Road
Crafers SA 5152

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Pests - watch out for these unwelcome critters

Adult lucerne fleas (Sminthurus viridis)

Small Talk adult lucerne flea

They may be only 3 mm long and wingless but they can inflict considerable damage on clovers, lucerne, and other cereals and crops. They lay eggs which remain dormant over summer and hatch during March–April. They tend to be a problem on loam/clay soils but generally not on sandy soils. Monitoring the development and spread of these pests is important so that chemical applications can be timed to act on young fleas that have not had a chance to breed. Systemic sprays can be used when damage is first detected. The known predators of this pest are unlikely to be an effective control measure on their own. A good grazing regime coupled with sound weed control of host plants should be adopted to avoid total reliance on chemicals.

Red-legged earth mites

Small Talk red legged earth mite

These sap-sucking mites can cause enormous damage, particularly if they attack the cotyledons (seed leaf) of germinating legume or native seedlings. As damage occurs, legumes display a silvery discolouration and native seedlings a white to yellowing discolouration. Once grasses, clover and native trees are well established, they are less susceptible to attack. Infestations are controlled if necessary, by boom spraying an appropriate miticide such as dimethoate or Lemat that will also control lucerne flea.

Cockchafer larvae

Small Talk cockchafer larvae

They feed on young growth of annual grasses and clovers. Permanent damage to pasture is rare but, if unfavourable conditions prevail the following spring and summer, recovery from the setback can be slow. High infestations of larvae can reduce the availability of feed in late winter/early spring, so stocking rates may need to be adjusted. Patches of bare ground often indicate their presence, particularly when there is germination in other areas of the paddock. Cockchafers are often found on higher slopes and in sandy loam soils; not so much in heavier, clay soils. Monitor for early signs. Spray with chlorpyrifos when larvae are actively feeding.

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Sign up for our monthly landholder events calendar for a list of upcoming field days, workshops and courses run by Natural Resources, community groups and industry groups by emailing

To view the latest calendar, click the link under the Education tab at

If you would like Natural Resources staff to run a specific event for your organisation, please get in touch.

Small Talk events

Field days/Forums


28 March

Ag Excellence Alliance

Ag Ex Forum
6–7 April
Adelaide CBD

Educational Horse Property Walk

13 May
Two Wells


Farm biosecurity and hygiene

March 2017
Contact: James Donnelly on 0400 488 786

Woody weeds management

April 2017
Contact James Donnelly on 0400 488 786

Landholder events are supported by funding from your NRM levy and the Australian Government.

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Handy hint - polypipe and vine guard recycling

Sustaining Endeavour provides a recycling and rebate service to growers in McLaren Vale, Langhorne Creek and Barossa regions for old polypipe and vine guards. Please help the service remain viable by ensuring that:

  • old polypipe is detached from wire and vines before being tightly recoiled using a recoiling machine (hand-wound coils are too loose) into bundles with a centre void space of no more than 100 mm
  • recoiled polypipe is tied off with a length of polypipe to get the highest rebate, though string, or a small length of fence wire is OK
  • vine guards are flattened and stacked to maximise density, and secured (conditions apply).

Drippers can be left in or taken out.

Provided growers contribute to dense loads for viable transport, a rebate will be returned through a participating regional supply store. Rebates can be put towards purchase of a range of Australian-made plastic products from sponsoring manufacturers and up to half can go towards local environmental projects.

So far 23 tonnes of plastic waste have been recycled with a target of 100 tonnes by July 2017.

Contact Uma from Sustaining Endeavour.

To participate, contact or 0452 537 266.

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Things to do - autumn

  • Identify winter germinating weeds and get ready to spray broadleaf weeds. Try integrated weed management, rather than relying solely on chemicals.
  • Monitor stock to ensure they maintain condition, particularly lactating animals who need at least double the food. Consider your supplementary feeding strategy.
  • Graze to reduce dry residues while maintaining groundcover above 70%. Oversow if necessary to bring up the percentage of perennial grasses and clovers.
  • If your soil tests recommend it, arrange with your contractors now to implement your lime and fertilising plan.
  • If you are lambing in winter be ready to activate your fox control plan. Contact your nearest Adelaide and Mount Lofty Ranges NRM Board office for advice and fox baits.
  • Look for early signs of common pasture pests, such as red-legged earth mite, cockchafer and lucerne flea.

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Related links

Natural Resources Adelaide and Mount Lofty Ranges