Low stock numbers across New South Wales and South East Queensland as well as a strong spring and relatively mild summer has enabled many graziers to cruise through autumn on green sub-tropical (or C4) grasses. With everyone now having had a taste of winter, in a lot of cases, while the quantity remains, the quality is gone. Frosted off sub-tropical grasses do not contain enough energy and protein to keep stock gaining weight. The high ground covers in some areas has also inhibited sub clover germination. In a lot of C4 and phalaris based systems, it is the sub clover that provides protein at this time of year, allowing stock to utilise the poor-quality carry over feed whilst still achieving moderate weight gains. Without suitable supplement, stock on poor quality frosted feed will likely go backwards. Below are some of the common questions we get asked when this situation occurs.
As a seed company – we would love to say “plant this and it will solve the problem”. But winter is well upon us and for many areas whatever is sown now will be slow. For the cow in figure 1, the best option for the immediate future is to supplement her diet with protein and energy. There are multiple supplements available, and you are best to talk to your local supplier to work out what is right for you.
While pasture sown now will be slow to establish, the rule “better late than never” applies. Late sown forages don’t have conditions that enable it to tiller out. To compensate increase your sowing rate. Also, consider that we want the late sown crop to get up and going, don’t skimp on the fertiliser! The best options for late sowing winter forages are:
Forage brassicas are often our go-to when we need quality feed in a hurry. Forage brassicas (rapes, canola, leafy turnips, bulb turnips) for winter feed should have been planted between January – March and they would be ready to graze now. Brassicas sown now can be killed by frosts if they emerge. They will most likely be slow, then vernalise – causing them to bolt up to flower before growing any meaningful feed. Look to sow forage brassicas such as Mainstar rape for quality spring feed in September, when soil temperatures reach 10°C and are on a rising plane. Mainstar will provide high quality feed for growing lambs and cattle.
I have planted feed, but it just won’t grow?
This is a common complaint this year. There are a lot of “hungry” ryegrass and oat paddocks, especially on the Tablelands and coastal areas of NSW. There are multiple reasons for this, however higher than normal spring/ summer growth followed by the deluge of rain in February/March are the two main reasons. Large rainfall events leach a lot of soil available nitrogen (N) and sulphur (S) through the soil profile particularly when they waterlog soils. Waterlogged soils are prone to denitrification, a further loss of N.
Several farmers have reported that their standard N application rates are not working. This has also popped up in some of our own demonstration and trial sites. If you have struggling ryegrass or oats consider increasing your N rates to boost growth. In colder conditions it is also worth considering the form of N applied with ammonia and ammonium forms of N more readily plant available than urea.
Once soil temperatures are below 8°C microbes stop converting elemental sulphur to plant available sulphate, which is an important nutrient required for plants to take up N. Therefore, talk to your agronomist about applying sulphur with your N applications from June-August.
Please note that fertiliser advice is general only. You should consult your local agronomist, and always observe appropriate grazing withholding periods when applying N fertiliser.
As always – if you would like any more information regarding your pastures or forage crops, please get in touch with your local AusWest or Stephens Pasture Seeds Territory Manager.