Soil testing highlights potential for lime at KI

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Soil testing has identified the potential to lift stocking rates by managing soil acidity for Kangaroo Island lamb and wool producer, Adam Buick.

Adam and his partner Alyce, along with Adam's parents Jeff and Andrea Buick, farm across two blocks totalling just over 800ha at Penneshaw and operate a grazing enterprise involving a self-replacing Merino flock and a first cross flock producing composite sired lambs.

The majority of the farm is in pasture except for 82ha which is cropped for stock feed.

The fifth generation farmer's focus on managing acidity is a direct result of his involvement in an MLA funded Healthy Soils Group which has highlighted the value of soil testing to identify soil conditions limiting productivity.

"I was really interested in soil testing, improving pastures and increasing productivity - being involved in the Healthy Soil Group seemed like the perfect opportunity," Mr Buick said.

The Kangaroo Island Healthy Soil Group held a number of workshops and farm walks and secured funding for members to invest in a technology aimed at increasing soil health and farm productivity.

The first workshop involved taking a soil core at the Buick's farm and examining the soil pH along the 1m soil core profile.

"Dad had hosted a field day 10 years ago which involved digging a soil pit in a paddock used for hay production where the clover was struggling - soil tests for the site back then showed the pH was 4.5 (CaCl2)," Mr Buick said.

"Soil testing was all new to me so when we were given a $500 budget to spend on improving soil health I took the opportunity to invest in soil testing. It was a chance for me to get my head around where our soils were in terms of fertility and soil conditions, where they should be and what our key limiting factors were to increasing pasture production."

The Buicks soil testing program involved eight paddocks with the aim of producing a snapshot of the current soil conditions.

Six of the paddocks had soil samples taken to a depth of 100mm while two paddocks had samples taken to 200mm.

"The test results showed we had good levels of phosphorous and potassium and low sulphur levels, but the standout figures in all the tests were the soil acidity levels," Mr Buick said.

"While one paddock had a pH of 5.0 (CaCl2), the majority of paddocks had low pH readings ranging from 4.6 to 4.7(CaCl2), showing they required lime.

"The results prompted us to put out a trial to see what response we would get to lime and a couple of things were clear - where we applied lime there was an increase in the clover content of the pasture and the clover was more vigorous in the pasture, resulting in better quality hay."

Mr Buick is now committed to a developing a liming program for the whole farm and using soil tests to monitor changes in pH over time.

"Ideally I'd like to lime the whole property at a rate of 2.5t/ha to bring the pH up about 0.5 of a unit, with the ultimate target of eventually getting the pH to 5.5 (CaCl2). Luckily we have local deposits of lime on the island which means lime works out at about $38/tonne delivered and a further $8/tonne for spreading," he said.

"We will be looking at applying lime to the surface of paddocks which are being direct drilled with new pastures as part of our pasture improvement program, but we will also spread lime on established pastures. We are working on the theory that if we can get the soil pH to 5.0 or better then we will have greater clover and ryegrass production which will give us the capacity to increase our stocking rate."

Visit the new soil hub: mla.com.au/healthy-soils:

Meat & Livestock Australia (MLA) recently launched its healthy soils hub, a go-to for producers looking to further their skills and knowledge in soil management to improve feedbase performance.

Here we talk to Michael Crowley, MLA's General Manager - Research, Development and Adoption, about the importance of soil testing.

Why the focus on soils?

Healthy soils are essential for pasture and crop growth. Here in Australia, our soils are highly varied and many are low in organic matter and nutrients, making it especially important to actively manage soil fertility and conditions.

Testing soils can help producers identify conditions limiting production and enables them to make targeted, data-based decisions to manage their soil resource. Information from soil analysis helps predict the size of the response to applied nutrients and match nutrient inputs to plant requirements for optimum growth. Improving soil health improves feedbase productivity and resilience to combat challenges in seasonal and climatic variability.

Despite the benefits, soil testing is underutilised in the red meat industry, so we've decided to bring it into sharper focus.

What are the benefits of soil testing?

Producers involved in MLA programs consistently comment that the information obtained through soil testing gives them more confidence when they're making decisions about fertiliser, ameliorants and soil management strategies. These decisions lead to many benefits:

What information is available to producers interested in soil testing?

MLA's healthy soils hub has been developed as a product of feedbase and adoption research by MLA and industry partners. The hub is a central source of information on soil testing, analysis, visual assessment and trials.

New resources have been produced to walk producers through each step in the soil testing process, offering digestible information to adjust practices one step at a time in alignment with whole-of-farm planning for high yielding, high quality pastures. This information is available to producers as How do I factsheets and as online training modules.

Also featured on the hub are guides for the visual assessment of soil issues, the enhanced soil phosphorus five easy steps tool and a series of case studies profiling producers who are seeing the benefits of soil testing in their businesses.

Many of MLA's adoption programs also bring producers together to discuss soil testing, analysis and soil management strategies.

Where do I start with soil testing?

Soil testing is a relatively straight-forward and low-cost process. It can be done across the whole farm or select paddocks and can be especially valuable to provide information about areas that are underperforming or that are due to be resown, renovated or treated.

Soil sampling involves taking a number of cores from the selected area of a consistent size and at a consistent depth, representative of soil conditions and different soil types. Samples should be taken when there is soil moisture, at the same time of year, each year, to reduce variability in soil conditions and allow results to be compared from one test to the next. Samples should be sent to an accredited testing laboratory. These processes are outlined in more detail on the hub.

Soil test results provide information on soil nutrient levels and soil conditions such as acidity, salinity and structure. Tests can identify any conditions limiting production and can be used to determine required steps or products to address deficiencies. Work with your agronomist to develop a plan that's suitable for your soil types, rainfall, pasture species and stocking rates.

What can we expect to see next?

The soil hub is the first of four feedbase hubs, developed to provide producers with practical resources to improve productivity throughout the season. The persistent pastures and legumes hubs will be released in April. Subscribe free to MLA's Friday Feedback e-newsletter to get the latest on these hubs and other news.

Visit the soil hub at mla.com.au/healthy-soils