Using sown pastures for grazing
Sown (or introduced) pastures can be a valuable way to lift the productivity and profitability of your grazing business. Often sown pastures are used to complement native pastures.
Benefits of using sown pasture in grazing systems
Sown pastures can play an important role in grazing systems by:
- restoring land condition - especially where little or no native pastures exist
- providing alternative fodder sources when spelling other pastures
- improving diet quality and growth rates - helping to turn off cattle at younger ages, targeting different markets
- filling feed year gaps - production can be maximised year round
- increasing carrying capacity
- providing special purpose pasture - for example, pasture to prepare first calf heifers and/or finishing prime stock
- reducing the rate of pasture rundown by using legumes in grass
- improving organic matter and providing disease breaks in cropping country.
Before using sown pastures for grazing
Before deciding to use sown pastures for grazing, consider:
- the soil and land type
- the cost of seed (including the cost of 1kg of pure live seed, and germination and weed percentages)
- if the introduced pasture will be more productive over time than the existing native pasture.
Find out how to select the right pasture species.
Sown pasture productivity
New sown pastures are most productive for the first 3-5 years. After this time they can experience what is known as 'rundown' (the tie-up of plant-available nitrogen in the soil, limiting productivity). By establishing legumes in sown pasture you can limit the extent of rundown.
To maintain production levels (by mobilising plant-available nitrogen) you can also;
- use fire.
Oversowing legumes into native pastures is a cost-effective way to improve grazing pasture. Depending on where you are located you can use species such as stylos, wynn cassia, tropical legumes, clovers and medics.
Sown pasture rundown
Sown pasture rundown is the decline in pasture production over time.
Read more about the effects, symptoms and causes of sown pasture rundown, and what options are available.
Tips for establishing sown pasture
When establishing sown pasture, remember that better seedbeds mean better establishment. It's also a good idea to:
- seek advice and plan ahead
- know the quality of the seed mix before planting
- reduce competition from weeds - through grazing and/or herbicides
- sow most grass and small legume seeds on the surface
- sow when there is good soil moisture at depth
- ensure you have good seed-to-soil contact.
When to plant
Planting times are dictated by the region, climate and choice of sown pasture. April to May is the best time for temperate species like clover, lucerne, medics and vetches. Summer pastures should be planted early or late between August and March. This will avoid the usual hot, dry conditions from October to December and take advantage of September and January/February rains.
A soil test is recommended before planting. If there are problems with soil health, you should fertilise before planting. Phosphorus, nitrogen and potassium are the key nutrients needed by a pasture. Some soils will also benefit from an application of lime before planting.
How to plant
Planting methods depend on the machinery available. Seeds can be spread using a rolling drum seeder, fertiliser spinner or combine drill with seed hoses removed.
Cover crops can be used to help establish pastures. Planting crops such as maize, oats and sorghum (at half their normal seeding rates) can reduce erosion on steep areas and help to shade seedlings in sandy soils. However, cover crops also compete with your sown pasture for moisture and, if the cover crops are grazed, this will impose extra pressure on the undersown pasture. Careful planning and management is required with cover crops.
Managing sown pasture
Your management plan for sown pasture must consider:
- Pasture growth - how to maximise use of pasture without adversely affecting land and pasture condition
- Pasture establishment - what to plant and how to prepare and sow
- Pasture management - ways to maximise the productivity and persistence of pasture, including weed control
- Grazing management - organise livestock, especially in the first year after planting, to make best use of improved pastures without damaging pasture composition or condition. There should be no grazing until the pasture seeds, and only light grazing once or twice during the first summer/autumn.
- Read more about sown pastures in Queensland: their place, their role and things to watch on the FutureBeef website.
- Use the pasture improvement calculator to help work out the costs and benefits of resowing.