Select soils with at least 50 centimetre (cm) of suitable root zone (freely drained, without hardpans or surface crusting). Oats have the reputation of tolerating poorer soils than wheat but the best crops are grown on the better soils. Oats are considered less suited to heavier clay soils than wheat or barley but the application of gypsum in such situations can improve yields. Waterlogging will severely reduce yield and quality so these areas should be sown earlier to reduce the detrimental effects. Oats can be grown in frost risk areas with yield losses being much lower than wheat.
For more information see Oats: paddock selection.
Legume based pastures and crops provide more nitrogen, which increases grain yield and protein percentage. Lower levels of applied nitrogen are needed following a good legume rotation.
Control of grasses
Pasture manipulation or spraytopping in the previous pasture. Control in the preceding grain legume is essential to reduce root diseases and allow early sowing. This is more important than for other cereals as chemical options for weed control in the oat crop are limited. Weed competition in the crop will reduce yield and grain quality. Plan to avoid inducing herbicide resistance in grasses.
Soil tests for phosphorus, potassium and pH can be used to help determine fertiliser requirements. Ensure phosphorus levels are adequate to reduce the risk of screenings.
Use phosphate and potassium fertilisers where indicated by soil test and trace elements as indicated by previous tissue tests. Fertiliser rates should be determined by using local recommendations based on budgeted yields and paddock histories. Nitrogen fertilisers can be applied with equal effectiveness at sowing (separated from the seed) or up to 6-8 weeks after sowing in most areas.
Use well filled seed from paddocks with a good fertiliser history. Adjust seed rate according to seed size and germination percentage to achieve a target plant population of between 185 and 250 plants per square metre for non-dwarf varieties (depending on variety), and more than 240 plants per square metre for dwarf varieties to obtain maximum grain yield. Treat seed to control pests and diseases where appropriate. Where there is a likelihood of waterlogging, higher seed rates should be used to compensate for reduced tiller numbers.
Variety and grade
Yield will be the main determinant of returns but grain quality has now become an important consideration. Choose a range of two or more varieties to suit likely sowing opportunities in your area and consider producing a high value, manufacturing variety if varieties suit your rainfall, soil type and rotation. In the higher rainfall areas dwarf oats are high yielding, more responsive to nitrogen fertilisers than non-dwarf oats, and are likely to be a good option for on-farm feed crops. Assess risk factors of varieties such as disease susceptibilities, herbicide sensitivities, dockages for downgraded samples, susceptibility to weather damage, coleoptile length, tolerance to acid soil and boron toxicity.
For more information see Oats: choosing a variety.
Seeding method and depth
Depth of sowing should not be greater than coleoptile length — 30-60 millimetres (mm) for most varieties. Preparation of a good seed bed is essential for the successful production of naked oats.
For more information see Oats: seeding and establishment.
Match variety to sowing time. Long season varieties should be sown first (late April to mid-May) and short season varieties later (June). As sowing is delayed the yields of all varieties will be reduced. Before mid-May, crops should only be sown where weeds were thoroughly controlled in the previous season. Both weed competition and waterlogging will reduce yields and quality more than delayed sowing. Lodging and shedding is reduced when sowing is delayed but in doing this, yield is also reduced.
Control of weeds in the crop by chemicals should be timely with respect to both weed size and development of the crop. Take care to rotate chemicals to delay inducing herbicide resistance where this may be a problem. Where weeds are likely to be a problem, the seeding rate can be increased up to more than 400 plants per square metre without reducing yields or quality.
For more information see Oats: weeds and integrated weed management.
Inspect crops regularly and control redlegged earth mite and lucerne flea during the seedling stage if necessary. Aphids should be checked and controlled from flag leaf stage and later in crops considered to be high yielding (over 4t/ha). Aphids can also transmit barley yellow dwarf virus (BYDV). If growing susceptible varieties in areas with moderate to high BYDV risk then spraying the crop with a synthetic pyrethroid at 4-5 weeks after sowing is advisable.
For more information see Oats: insect pests.
The major diseases that effect oats are stem rust, leaf rust, barley yellow dwarf virus (BYDV) and Septoria avenae blotch. The severity of these changes with seasons.
For more information see Oats: leaf diseases.
First harvest the varieties that are likely to shed or lodge. Delaying harvest can lead to significant lodging and shedding due to crop movement in the wind. Care must be taken when harvesting milling varieties to minimise the amount of dehulled grains. Consider management of stubble for the succeeding crop (straw length and spreading) and collection of grass seeds to reduce weeds in the next year. Hull-less oat varieties are susceptible to harvest damage adjustment to the harvest is therefore critical.
For more information see Oats: harvesting, swathing and grain storage.
Choose a suitable variety for the anticipated market. Increase seed and nitrogen fertiliser rates by at least 20% above those for a grain crop. Pay particular attention to soil test results for potassium if repeated hay crops are taken from the same paddock. There are specific requirements for the export markets that are different to usual on-farm needs. These include earlier cutting times, green hay colour, low moisture content, freedom from weeds, and thin-strawed varieties. At all stages of the hay crop growers should check exporters specific requirements if they are interested in this market.