Keys to successful pasture establishment
11 Mar 2022
PRODUCTION ADVICE & NRM NEWS - MARCH 2022 - AGRONOMY
By Adrian Smith
Senior Land Services Officer - Mixed Farming Systems
P: 03 5881 9900 | M: 0447 778 515 | E: adrian.smith@lls.nsw.gov.au
As we head into autumn again, many producers will be thinking about their autumn and winter feed requirements – and establishing new or renovating existing pastures may be front of mind.
Apart from the obvious livestock benefits, pastures are well known for improving soil structure, soil fertility (where there is a legume component), and there is good evidence they can maintain (and perhaps improve!) soil carbon levels.
Before we consider the ‘hows’ of establishing pastures, we need to examine the ‘why’. A few of the questions to reflect on include:
- Is the pasture short or long term?
- Are there specific paddock issues, such as being prone to waterlogging, soil acidity, etc?
- What species are suited to my climate and rainfall?
- If irrigating, is the intent to fully or partially irrigate?
- What role will pastures play in grazing (and whether sheep or cattle), hay production etc?
- Do you want a single species, or a range and diversity (including, grasses, legumes, herbs, annuals and perennials etc)?
- Can you manage your pasture over the long term?
Above: Productive pastures will provide high-quality feed for livestock – the keys to success are in the planning and preparation. (Source: farmingahead.com.au/pastures)
These are only some of the questions producers need to be clear on before they set their seeder up and hook on the tractor!
But once these are answered, there are several clear steps to follow to give your newly sown pastures every chance of returning a good investment.
What are the keys to a successful pasture establishment?
Establishment costs of new pastures can be high. We need good establishment in the first year to guarantee the pasture is productive over its lifetime.
- Planning
Establishing new pastures can cost well over $300 per hectare, so it is important to do everything you can to get a good result! Plan well in advance of sowing - considering factors such as soil limitations and weed and pest control.
- Soil fertility
A soil test will identify any soil issues which need correcting. Issues to be particularly aware of are soil acidity, nutrient status and potential imbalances or toxicities (such as high Aluminium levels).
- Choose the right variety
Choose your pasture species based on soil type, rainfall (or irrigation) requirements, maturity, and disease and waterlogging tolerance. A mix of legumes and grasses will provide high-quality pastures for your livestock.
Always use high-quality, certified seed. Seed cost is a relatively small component of the overall budget, and the certified seed will ensure high germination rates and minimise impurities.
Seed treatment is also an important consideration. If sowing legumes, inoculation with the correct strain of rhizobia is essential – particularly where there is no recent history of legumes in the paddock. Local testing of rhizobia strains in pasture legumes (e.g. sub clover) has shown relying on pre-inoculated (coated) seed to be unreliable. If using pre-inoculated seed, ensure it is sown within six weeks of the inoculation date. Consider other seed treatments and/or primers to minimise problems caused by pests and diseases.
- Correct seeding rate
Lowering seeding rates will result in lower production, whilst providing greater opportunity for weeds to germinate and establish. Always take note of the recommended seeding rate – and if conditions are less than ideal, consider increasing the rate.
- Sow with good soil moisture
Favourable conditions are desirable for at least a couple of weeks after sowing. When sowing dryland pastures, aim to sow with a good profile of moisture. Sowing into the late autumn-winter will reduce pasture establishment, growth and production.
- Soil temperature
Apart from the obvious issues around increased water requirements, high soil temperatures will inhibit the germination of many annual pasture species. The ideal soil temperature (at sowing depth) for ryegrass is 15-250C. The most practical indicator is to use average daily air temperature over a period of 7-10 days.
- Seedbed preparation
Everyone has their own ideas of what works best for them – a prepared seedbed, direct drilling, broadcasting etc. Whatever method you choose, important things to remember are:
- Sow seed shallow. Sowing too deep will reduce germination and establishment, whilst dropping seed on the surface can often lead to ‘harvesting’ by ants, or the seed drying out before the root enters the soil.
- Aim to sow to a depth of 1-2 cm, cover lightly with soil and get good seed-soil contact (use a rubber tyred roller or similar).
Above: Accurate seed-soil placement and contact is important for good germination of small seeds (Source: WMLIG, 2018)
- Monitor
Once your newly established pasture is on its way, keep an eye out for weed germinations and any pests – in particular red-legged earth mites and aphids. Get on top of these early, to minimise costs and any impacts on pasture productivity.
- Grazing management
Successful pastures, once established, are very dependent on suitable grazing management in their first year:
- Do not graze too early – plants must resist being ‘pulled out’,
- Graze lightly to encourage tillering and good root development, and
- Ensure good seedset by minimising grazing during the flowering and seed production period.
Landholders wanting further advice on their pasture management should contact their consultants, advisors or resellers, or a member of the Agricultural Extension team at Murray Local Land Services.