Depending on whether or not your entire property is in permanent pasture, or part of a longer-term cropping rotation, the frequency of soil testing may differ. For cropping systems, annual soil testing is recommended. Generally, the more intensive the farming system, the more frequently the testing should occur. As a guide for perennial pasture systems, a sampling plan that aims to test the entire farm every 3 to 4 years is sufficient.

Dryland grazing systems occur on most soil types throughout Tasmania, and management therefore differs based on soil type. It is useful to understand the particular limitations of the given soil type and not to use a recipe for establishing pastures across a farm. For example, a lucerne stand is unlikely to succeed on a heavy clay that sits waterlogged for the better part of winter. The LISTmap is a free online tool which provides many informative data layers such as soil type, geology, contours, and groundwater information. Soil mapping surveys may be available for your farm on the LISTmap, via the Soil Types layer and can provide an indication of which soil types may be on a farm. This information is large-scale and not site specific, and should be corroborated with information from a soil survey and soil tests.

Pasture composition should be suited to the predominant soil type, climate, and topographical considerations for each paddock. For example, steeper slopes may warrant the establishment of long-term deep-rooted species to help reduce the risk of erosion. Areas of natural salinity on the farm may be limited to more native grasses or saline tolerant species. Salinity amelioration is mentioned further in Appendix 1. Ideally, within reason, managing paddocks based on land capability and soil type is best for ease of management, and success of pasture establishment. It’s important to understand the dry matter production potential and monitor actual production per hectare in order to make the most efficient use of your feed base, and ensure that stock are performing well. There are several methods from simple to complex that can be used to estimate dry matter production such as:

• Biomass cuts which are weighed before and after drying
• Rising plate meters
• Electronic probes
• Rulers such as the MLA Pasture Ruler.

Whilst all of these methods vary in accuracy, the point is to understand how pasture performance varies by soil conditions, pasture type, stocking rate and season. A higher level of accuracy in measurement will allow a higher level of accuracy in management, according to what suits the system. Maintaining ground cover is important, no matter how dry matter production is monitored. Taking livestock weights is a good monitoring tool to check whether soil and pasture management are meeting production goals.

Suitable pasture species for each different management area must be selected in order to maximise your feed base. Species For Profit by DPIPWE (2021)⁹ provides a comprehensive overview of commonly grown pasture species and their strengths and limitations. Seed companies often provide region-specific advice on perennial pasture cultivars, such as the Perennial Pasture Guide Extensive Systems (2022) by Barenbrug Australia or Tasmanian Pasture Guide (2021) by S&W Seed Company.

Pasture and feed testing are recommended to ensure a balanced diet. Refer to the forage project under the TasFarmingFutures website (http://www.tasfarmingfutures.com.au/tasforageabout) for information on feed sampling, feed test interpretation and assessing feed value.

The importance of soil life is commonly highlighted in connection to nutrient cycling and availability to plants, and in pasture systems our ‘micro livestock’ play a very important role. Pollinators such as bees, butterflies and moths, predators such as ladybugs, and decomposers such as beetles, ants and earthworms all contribute to nutrient cycling and the control of pests.

Dung beetles are the smallest type of livestock that farmers manage in perennial pasture systems, and are possibly one of the most valuable. Dung beetles play an essential role in enhancing nutrient cycling by efficiently recycling organic matter and thus nutrients contained in animal dung. By burying dung, dung beetles incorporate organic matter into the soil that would otherwise stay on the soil surface for a long time, especially in dry conditions. This beetle activity promotes the release of essential nutrients, such as nitrogen, phosphorus, sulphur and potassium. This process, in turn, leads to an improvement in soil fertility, ultimately resulting in better pasture growth.

Dung beetles help to improve soil structure by digging burrows and tunnels in the soil, which promote better aeration and water infiltration, two key factors for good plant growth. These tunnels also allow for better water retention in the soil, leading to improved drought tolerance in the pasture. The channels also improve root penetration which is important for accessing a greater volume of nutrients and water than roots could in a denser soil.

Beyond the benefits to soil health, dung beetles offer ecological benefits to livestock. By efficiently removing dung from the pasture, they significantly reduce the breeding sites for flies and parasites, and reduce the risk of fly-borne diseases by disrupting the breeding cycle of flies and parasites, ultimately contributing to better health outcomes for livestock.

Dung beetles should be an integral part of any healthy and sustainable dryland pasture system, offering benefits to soil health, crop yields, and animal welfare. As such, it’s important to take proactive measures to protect and support these insects by avoiding the use of insecticides that can be harmful to their populations, and limiting drenches where possible. Information on how to minimise risks to dung beetles from drenches and pesticides can be found at www.dungbeetles.com.au(Dung Beetle Ecosystem Engineers).

Through the website, advice on assessing beetle activity throughout the seasons can be found. Dung beetles in Tasmania are predominantly active from mid-spring to mid-autumn, however, increases in fly activity occurs in early spring, and parasites can breed year round. Assessing the seasonal performance of dung beetles can help identify limiting factors or seasonal constraints so that a dung beetle population performs well all year.

Fertiliser may be one of the single biggest input costs in perennial pasture systems, so it makes sense to maximise fertiliser use efficiency, and minimise wastage and runoff. Efficient fertiliser use can also help in reducing overall farm emissions, as well as being good for gross margins. Nutrient Management for Farming in Tasmania (2023) by Bill Cotching provides a comprehensive guide on fertiliser budgeting and how to develop or reassess a fertiliser and nutrient management plan. Soil and tissue/feed testing should be used to guide the application of fertilisers and soil amendments.

As emphasised previously, fertiliser is not a ‘silver bullet’ solution for maximising pasture growth and soil health. In most cases, there is no direct relationship between fertiliser inputs and dry matter production because there are many other influencing factors, as highlighted in this Guide. Still, when well-managed, fertiliser and other soil amendments will have the multiple benefits of increasing pasture growth, supporting biological activity, building soil carbon, and importantly ensuring animal health and productivity. Care must be taken to reduce the risk of environmental impacts from fertiliser runoff, particularly in areas of higher rainfall and on lighter soils. Soil and nutrients are easily lost on slopes and when pasture cover is poor.

When using biosolids, manure, or effluents as soil amendments, care must be taken to avoid potential risks associated with their use. Manures from poultry or feedlot should be composted and tested before application. Effluent testing is recommended. Soil tests should be used to determine application rates to avoid oversupply of N and P and potential nutrient imbalances affecting pastures and livestock, and reduce the risk of nutrient leaching into waterways. Refer to Tasmanian Guidelines¹⁰ when using effluent.

Biosolids contain valuable nutrients, but can also contain heavy metals and other contaminants that may negatively impact soil health. The EPA guidelines provide thresholds for contaminant and heavy metal concentrations. To mitigate the risk of negative impacts, soil testing should occur just before biosolid applications to accurately measure the risk of nutrient leaching or run off. Annual soil testing is recommended to assess for changes and accumulation over time. Refer to Tasmanian Guidelines¹¹ if interested in using biosolids.

It is worth mentioning that when grazing native pastures there are restrictions on the activities that can occur. Lowland Native Grasslands of Tasmania are listed as critically endangered communities under the Environment Protection and Biodiversity Act 1999. Whilst grazing isn’t restricted on these native pastures, altering grassland composition with amendments such as fertiliser or oversowing with exotic species needs consideration and potentially Federal approval. Further clearing and development must also be investigated as it may not be legal.

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^⁹https://nre.tas.gov.au/Documents/Species-for-Profit-Book_Web.pdf

¹⁰ https://epa.tas.gov.au/Documents/Guide%20to%20Regulatory%20Expectations%202020.pdf

¹¹ https://epa.tas.gov.au/Documents/Tasmanian%20Biosolids%20Reuse%20Guidelines%202020.pdf