Irrespective of whether your late-cut grass silage is the third of a traditional three-cut system, or the fourth, fifth or sixth of a multi-cut approach, it is definitely worth doing a proper job.
Because improved grass growth towards the end of the season has the potential to produce silage quality similar to first cut.
True, it may not yield as well. But it has the capacity to deliver good protein and energy levels. Which is exactly what’s needed for more litres of milk from forage.
And, if you are on a multi-cut system, you may be glad of that extra yield.
One of the secrets to unlocking the potential of late-cut grass is to remember that it is growing in different conditions to cuts taken earlier.
A return to higher soil moisture levels will increase the availability of soil nutrients. Any extra nitrogen taken up will tend to buffer the effects of the beneficial acid produced during fermentation.
That’s exactly what you don’t want, because this acidity is needed to ‘pickle’ the grass – preserving it against undesirable bacteria and moulds that would otherwise feed on its dry matter and nutrients. Grass will also be wetter.
The solution? Basically, a three-step approach:
Firstly, get grass tested to check residual nitrate levels. That way you know what you’re dealing with. You want a nitrate-N of less than 0.1% of DM.
Secondly, don’t make soggy silage. Use good wilting practice – such as tedding – to reach a target dry matter of 28-32%, or possibly higher. With drier silage, there’s less moisture, and so less dilution of beneficial acid.
It also means less sugar will be required for fermentation, which is important because with shorter days, sugar levels in the crop are likely to be lower. By wilting to your target DM quickly, you also minimise sugar losses through grass respiration in the field.
Finally, achieve a good fermentation, to ensure there’s enough ‘pickling’ acid.
For example, as well as sheeting clamps properly to keep air out, make sure you consolidate well to remove as much air as possible in the first place. Remember, you can only properly "Consolidate in 15cm/6 inch layers" rather than the "top".
And make use of a proven silage additive. Proven to deliver a more efficient fermentation and better silage, but also proven to produce a silage that delivers more litres of milk per cow per day. Trials have shown that treating with a proven additive, such as the MTD/1 strain of Lactobacillus plantarum in Ecosyl, can improve milk yield by an average of an extra 1.2 litres per cow per day. After all, that’s why we make silage in the first place.