A grazing cereal can significantly help weed control and provide quick, bulk, early feed.
Nitrogen and forage nitrate levels
Nitrogen is necessary for productive growth, including the build-up of a feed bank and should be applied at sowing. After sowing, avoid applying nitrogen before grazing.
Plant recovery after grazing can be achieved with application of nitrogen. Nitrogen applied to plants can result in high forage nitrate levels.
Sheep nutrition and health
Useful for grazing to fill a winter feed gap or if the flock has increased feed requirements for pregnant ewes and during early lactation, grazing cereals are effective for liveweight maintenance or gain with lower levels of food-on-offer than would be available from pastures.
However, young growing crops often contain an imbalance of potassium, sodium, magnesium and calcium that can cause metabolic disease such as sodium deficiency, hypomagnesaemia or hypocalcaemia. These diseases can lead to mortality in sheep.
Young wheat carries higher risks of metabolic disturbance than other young cereals for sheep.
Cattle nutrition and health
Grazing cattle on cereals is a good way to reduce the cost of purchasing supplementary feed during the autumn / winter feed gap.
Grazing on crops may also lead to higher animal production if the grazed crops have a higher nutritive value than feed that would otherwise be on offer during winter. This in turn helps you get stock to market earlier.
Tips to consider before introducing cattle to lush pasture or crops:
- Feed cattle with hay, so they are not introduced to lush feed on empty stomachs.
- Ensure they have access to a source of fibre.
- Supplement feed with magnesium, calcium and salt.
- Vaccinate cattle against pulpy kidney, particularly young stock.
Introduce stock once the plants are securely anchored in the ground and when there is enough biomass available for the desired stocking rate. Cattle generally require time to adapt to different sources of feed and to be able to utilise it effectively.
During this adaption period animals may not be able to gain the maximum nutritional benefit from the feed and animal performance may suffer.
Seasonal conditions, such as a late break can impact the biomass production for grazing.
Grazing can start as soon as cereal plants are well anchored and when the amount of forage exceeds one tonne of dry matter per hectare. To test if plants are anchored, use the ‘tug test’. Twist and pull a handful of plants at the same time.
The plants pass the tug test if they remain in the ground. The decision about when to start grazing is much less important than the decision about when to stop. Don’t graze below the height of a tennis ball or if nodes are present.
Balance stocking rates to prevent underuse or overgrazing of crops. CSIRO research suggests that a useful ‘rule of thumb’ is to graze with about 1000kg of stock liveweight per hectare. This could be, for example, 33 sheep at 30kg each or three cattle at 330kg each.
Sources: MLA website, GRDC website, NSW DPI, Agriculture Victoria