Some farmers are, or have already moved to harvest their second-cut silage.

This, for many, signals the end of the last large cut of the year, with excess usually taken out in the form of bale silage from now on.

However, some farmers should consider a third cut.

Second-cut silage

First and foremost however, after second-cut silage, it is important that the nutrients taken off the field are replaced.  

A bale of silage weighing 800kg fresh [200kg dry matter (DM)] has removed 1.6 units of phosphorus (P) and 10 units of potash (K) from the paddock.

So the removal of 3,200-4,000kg of fresh grass/ac will mean that between six and eight units of P/ac and 40-50 units of K/ac are required for replenishment.

As a rough rule of thumb, 50 units K/ac is enough to change a soil K index – which means a paddock/field could go from index two to index three, or vice versa.

Fodder budget

Before deciding whether or not to harvest third-cut silage it is important to firstly determine how much fodder is on your farm.

A fodder budget should be completed to determine the farm’s current fodder supplies.

When completing a fodder budget all the silage stores should be taken into account, including pits and any bales that have been made.

On some farms, bales that were made earlier in the year will have been used, so it is important to have an accurate count on the number of bales present on-farm.

Once the budget has been completed, one can determine if a larger third-cut is needed.

Third cut

Even if your fodder requirements have been met it may be no harm to cut some extra grass for silage.

No one knows what the future holds, and having extra silage in the pit or in the form of bales could be very helpful.

A bad backend or beginning of next year could result in stock needing to be housed for longer, thus meaning that more fodder would be required.

There also remains a concern that less silage will be available over the winter for purchase, so farmers may need to meet fodder requirements from inside the farm.

In a situation where one is still short of fodder after a second cut, then a third cut should most definitely be planned too.