WestVic Dairy News - September 2010 Edition
Five tips for quality silage
By Michele Ryan and Helen Chenoweth, DPI Warrnambool
With silage season on the go, there are five key things farmers need to remember to gain the best possible return for their effort.
1. Only lock up pasture that is surplus to requirements.
On most farms in a reasonable year, pasture growth will generally exceed animal requirements in early to mid September. With the wet conditions of August (and at the time of writing in mid-August), pasture growth may be slower than usual but an excess will come some time in September! Locking up feed to cut that is still needed by milkers is generally not a good strategy.
2. Use nitrogen to increase dry matter (DM) yield, and cut pasture within six weeks of application.
Once cutting is delayed beyond six weeks, the quality of the silage declines more
rapidly than if no nitrogen is applied. This results in large quantities of low quality
silage unsuitable to feed cows in the early stage of lactation. By using rates of nitrogen up to 50 kg N/ha, responses of about 12 kg DM/ha for every kg N applied six weeks after application, can be expected. Remember to apply to paddocks that will give the best response. Paddocks that have a good ryegrass base aren’t still waterlogged and with better overall soil fertility will provide the best response.
3. Be prepared to cut pasture when the ryegrass component of the sward is just reaching early ear emergence.
In most years, this is normally about the last week of October to the first week of
November. However the species and variety will dictate date of maturity such as an early versus late maturing annual ryegrass.
4. Use tedders or conditioners to increase the drying rate of cut material and reduce the wilting period.
It has been shown that the use of tedders and conditioners has a substantial beneficial effect on both final silage metabolisable energy and crude protein levels.
The length of the wilting period will be dictated by the type of silage to be made
and weather conditions. With reasonable drying conditions and a mechanical treatment such as tedding or using a mower-conditioner, the desired dry matter content should be reached within 24 to 48 hours. Extra tedding may be required early in the season, especially after the wet conditions through August most areas have experienced.
5. Ensile material quickly and seal well.
It is important to ensure that the material being ensiled is tightly packed into either a pit or the bale and that it is sealed promptly. The ideal dry matter of pasture for pit
silage is 30 to 35 per cent. Any lower and effluent may be a problem and, if it is higher, compaction may be difficult. Bale silage should be about 40 to 50 per cent. With dry matter content at this level, reasonable fermentation should occur, reducing dry matter and nutritive losses and also reducing the chance of spoilage.
If you would like to discuss your situation, contact Michele Ryan on (03) 5561 9914.
