Gippsland - How Now Gippy Cow
October 2010 Edition
What to do with underperforming paddocks coming into Spring?
On many farms there will be paddocks that are performing badly. To work out the most profitable option for these paddocks for the rest of the season, a number of questions need to be answered and a number of factors need to be considered.
Firstly, some critical questions.
- What is causing the paddocks to be performing badly? For example: weeds, poor density of desired species, poor establishment of new crop/pasture, poor soil fertility, soil structure issues e.g. compaction, poor grazing management, insect attack or a mystery?
The most important thing to consider before deciding what action should be taken is to work out what is causing the poor crop/pasture. It pays to get a second opinion – so don’t put off getting your agronomist out or doing a soil test. Unless the reason for the poor result can be addressed it is likely the same result will be repeated in the coming season.
- What do you want out of the paddock? - Do you want to: grow a summer crop, establish a perennial in it (now or next year?) or get the paddock fixed so you can grow a good crop or pasture next year?
- When will the feed be available? How reliant are you on the paddock producing spring feed for you? It is unlikely that you will get something established in time to provide a valuable grazing contribution over the spring. Most crops require eight weeks or more from sowing to grazing (some 14 weeks).
Other factors that need to be considered are: Is the paddock able to be irrigated (water or effluent) and what is the long-range forecast predicting might happen to seasonal conditions?
Summer crops
One option is to sow a summer crop and then sow the perennial pasture or annual crop/pasture in the autumn. The summer crop, if managed well, will provide a lot more feed per megalitre of water or effluent than a newly sown perennial pasture over the summer.
Often the major advantage of the summer crop option is that the chances of a successful establishment of the perennial pasture or annual crop or pasture the following autumn is much more likely. If thinking of this option consideration also needs to be given to impact on this year’s spring growth period. A summer crop isn’t going to provide any feed over the peak growth period. Less silage or hay will be made.
Some of the crop options are:
- Summer grasses (millet and sorghum)
- Perennial grazing herbs and mixes (plantain and chicory / mixes with brassicas, clovers or millet)
- Forage brassica (regrowth types and turnips)
There are advantages/disadvantages to each of these options and finding out correct information on each option is important.
Most summer grass crop options like millet require soil temperatures to be 14C or higher and sorghum 16C or higher before being sown.
This normally doesn’t happen until November at the earliest, meaning feed won’t be available from them until January. Brassicas have potential pest problems but are excellent quality. Herbs take longer to reach peak growth rates but, being a perennial, will also help fill an autumn feed gap.
Perennial pasture
Sowing a perennial pasture in the spring requires more attention to detail than autumn sowing. It will produce less feed over its first spring/summer compared to an established or autumn-sown perennial pasture. It is also very important to make sure you have the paddock correctly prepared and all potential weed issues under control first. With this said, it is possible to get a good pasture established in the spring. The new pasture needs to be well established before any moisture stress. It will be very sensitive to over-grazing in summer and should be spelled while conditions are hot and dry.
Costs and risks
Consideration also needs to be given to the cost and risk of undertaking each of these options compared to sourcing the feed from some where else (e.g. grain or hay).
Improving the existing pasture
If you do not plan to spring-sow underperforming paddocks then the following points might help improve their performance:
- Control weeds to give desired species the best possible chance and/or to reduce the weed burden for the following season.
- Fertiliser like nitrogen might be able to give pastures a boost if there are enough desirable species there to get an economical response. Alternatively, nitrogen might be better put on the better paddocks to try to grow more feed.
- Good grazing management is important to give desired species the best chance of optimal performance.
- Start planning how to get the paddock back to performing well.
Tom Farran and Greg O'Brien,
Dairy Extension Officers, DPI
