For farmers trying to get more from forage, a multi-cut grass silage system might be a great option. Silage is cut earlier and more often, with around 4-6 cuts per season cutting every 28-30 days.
Although it may not suit all producers, for those that can exploit the system it can raise their profits. The extra harvesting costs will be outweighed by the additional milk produced.
Low quality forages require high energy and or protein purchased feeds to make up for shortfalls, which generally are more costly. By improving the quality of forages used in the diet, the need for high specification purchased feed is minimised.
The success of the multi-cut system starts by ensuring that leys are in the best possible condition, which for many will be more frequent reseeding, or overseeding than is currently practised. By keeping leys in better condition they will yield more dry matter per acre and will utilise fertiliser more efficiently.
The growth habit of grass makes it ideal for multi-cut. Grass regrows in a slow-quick-slow pattern, so more frequent cutting can increase the period of quicker growth. The table below shows the effect on silage yield and quality when taking 5 cuts compared to 2 larger cuts.
Parameter | 2 cuts | 5 cuts | Results |
Average tonnes DM/ha | 12.7 | 17.1 | +4.4 |
Average ME (MJ) | 10.6 | 11.1 | +0.5 |
Energy Yield (MJ/ha) | 135,255 | 190,323 | +55,068 |
Average D-Value (%) | 67.8 | 71.2 | +3.4 |
Crude Protein (%) | 14.8 | 18.5 | +3.7 |
Protein Yield (kg) | 1,880 | 3,164 | +1,284 |
The data shows the significant yield improvement of energy and protein per hectare.
When using a multi system a D-Value of up to 75 is targeted. This would result in approx 12.0MJ of energy per Kg of DM. It shows that there is a potential to achieve as high a feed value as in grazing systems.
Chop length should be varied according to DM and quality. If it is all young leafy material and 32% DM then 3-5cm. If it’s 28-30 DM then 5cm minimum, but if it’s wetter and below 28 then it needs to increase in length even up to 10cm at 22% DM.
Younger, leafier crops are likely to be easier to consolidate in the clamp than older, stemmy ones. However continue to fill in layers of maximum 15cm deep for good consolidation.
Although the higher protein content of younger-cut grass is a benefit, nutritionally it can make the silage more difficult to ferment. Younger grass can also be lower in sugar, so not only can the acid needed to preserve the silage be in shorter supply, it can also be ‘neutralised’ to some extent by the higher protein.
Adding a high-quality silage additive which delivers proven ‘good’ bacteria into the silage is important to deliver a fast, efficient fermentation. In this way, as much lactic acid is produced in as short a time as possible (rapid pH fall) before the protein exerts its full buffering effects.
Varietal choice is very important to match the system to the growth habit of the grasses.
Browse our range of grass mixtures here