Milking the Weather - March 2011 Edition
Planning for the season ahead
by Greg O’Brien, DPI Ellinbank and Tom Farran, DPI Tatura
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Photo above: It won’t take much rain for a wet winter scenario |
The wet summer in many areas has provided benefits and some challenges for the season ahead. Many pastures have flourished leaving them in good shape for the coming year. A good profile of moisture in the soil will support establishment of new pastures and crops. There is a level of certainly for irrigation farmers about the security of water in the short to medium term.
On the downside a major summer weed problem has risen in many areas, making successful establishment of autumn crops and pastures more difficult. Some paddocks have been affected by water logging. The wet has also provided a green bridge over the summer to carry over many plant diseases. In addition, a neutral to slightly wetter three month outlook for Victoria (from the Fast Break Newsletter), combined with a full soil moisture profile will mean it won’t take much autumn and winter rain to give farmers a wet winter scenario.
More home grown feed
There is currently more home grown pasture and crop on most farms, together with high silage and hay reserves. This means there is a lower requirement for other parts of the herd feed portfolio such as purchased fodder. At current prices, feeding concentrate such as grain will be a popular strategy for balancing the diet and keeping a profitable level of milk production.
With the onset of cooler weather, pasture will jump in quality and more newly established crops and pastures should become available. This will require a rethink of the feed portfolio as these newer crops and pastures may be lower in fibre, creating an opportunity to reduce the low fibre concentrate and make use of the large reserves of lower quality fodder reserves.
Early sowing
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Photo above: Early sowing could be an option |
With good soil moisture reserves, early sowing of pasture and crops can be undertaken with greater confidence this season. However, there is still a risk that some regions, such as eastern Victoria could experience a soil moisture shortage during autumn. This may cause establishment concerns for pastures sown too early without back up irrigation. Large seeded species handle a false break better than small seeds.
Where an early sowing is successful, there will be much greater production over the autumn/winter compared to those sown later. If pastures plants are not well established before the onset of colder conditions they may produce little growth until late August.
The irrigation challenge
Over the extended dry period many northern irrigation farmers logically changed to growing alternative crops that provided more feed from the limited water available. Now that there is increased certainty in water availability for the coming season, many are reviewing how they use their land. Newer water management tools (such as the carry-over policy) can be used to increase control over water price and availability – and with this you can review what you sow.
Traditionally, irrigated perennial pasture provided a relatively cheap feed source underpinning profitable dairying in northern Victoria. Although it has a relatively high water requirement over the summer months it provides grazing all year round and avoids the costs associated with many other crop choices.
The main choices this year will be whether to the use perennial pastures in proportion to other crops that won’t need a commitment to summer irrigation (eg lucerne). Water could be used over summer to grow alternative crops, but growing annuals increases the costs associated with sowing and creates gaps in the feed supply during establishment.
On the other hand there is also the reality that farms have an upper limit of irrigation water that can be applied (annual water use limit) over a season, and this will mean that irrigating the whole farm as a perennial planting may not be a realistic option.
Calving patterns may have changed, as well as infrastructure and equipment. These can also influence the appropriate balance of forage types grown.
Consider the following:
- The advantages and disadvantages of perennial ryegrass.
- The growth habit of perennial ryegrass compared to annuals.
- Whether perennial ryegrass will fit easily back into your system?
- Understanding what might happen with water availability over coming seasons – can you manage the risk?
- How much area should you sow down to perennial ryegrass?
Planning for the wet
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Photo above: Consider maintenance of tracks, drainage and stand off areas. |
There is an increased chance of soils becoming too wet this winter and spring. The main risks are lameness, mastitis, reduced pasture/crop production and utilisation. Tasks to consider include track maintenance, drainage, setting up stand off areas and providing feed supplements. Works need to be completed before it becomes too wet. There may be a need to consider the implications of lower growth and utilisation in the feed plan.
There are also things to consider now while planning this year’s pasture and crop renovation. Many of the crops that have become popular on dairy farms over the last couple of years such as cereals are often more suited to drier conditions and struggle in wet conditions. Most crops are also very susceptible to pugging. Ryegrass and clovers tend to handle wet conditions relatively well (up to a point).
Paddock preparation and sowing needs to be considered carefully. On most soil types if you cultivate soils in the autumn, then they are more prone to pugging over the winter period. This may need to be balanced against the need to achieve a good seed to soil contact at sowing and to have a nice friable soil for the new plants to grow in. If you don’t achieve good establishment then you are going to have a low yielding crop or a pasture that will need renovating again.
