‘There is no point in talking about silage quality in May – Now is the time’

Now is the time to focus on silage quality not next May, according to Teagasc’s Michael Daly.

The Teagasc Drystock Advisor said that the decisions made on beef farms over the next couple of weeks will have a big impact on silage quality next winter.

The Tipperary-based advisor said that farmers should try and graze their silage swards before letting them out, as cutting grass that has grown over the winter will have a negative impact on silage quality.

Research shows that silage swards that have not been grazed have lower digestibility levels. The silage quality will fall back to 62-63% Dry Matter Digestibility (DMD) if the sward is not grazed.

“One of the key drivers of profitability on a beef farm is good quality silage. Farmers should avoid compensating for poor quality silage with expensive meal,” he said.

silage quality
Sward showing signs of leaf death, this sward should be grazed before closing.

Fertiliser applications

Daly spoke at a recent beef farm walk in Roscrea, Co. Tipperary, where he said that farmers should allow for an adequate amount of time between spreading Nitrogen (N) and cutting silage.

“This allows for the N to have fully grown out of the grass.

If you spread 100 units of N, it will take 50 days for the N to grow out of the grass.

Also speaking at the farm walk, Teagasc’s Claire Mooney said that farmers should aim to spread 80 units of Nitrogen per acre on old swards and 100 units of N per acre on recently reseeded pastures.

She said that the N applied can come from a number of different sources, including slurry, urea or Calcium Ammonium Nitrate (CAN).

She said that slurry provides about 6 units of Nitrogen for every 1000 gallons and farmers should spread 3,000 gallons of slurry per acre on silage fields.

Mooney also said that silage tends to take a large amount of Phosphorous (P) and Potassium (K) out of the soil and as a results farmers should spread fertilisers to maintain the soil fertility levels.

“At index 3, the soil grows the crops and you should replace what the silage crops removes. When soils are at index 1 and 2 for P and K, you replace what the soil removes and add a little extra to build to index 3,” she said.

Silage fertiliser applications:
  • Index 3 soils: 9 units of P and 12 units of K for maintenance (1.5 bags of 18:6:12)
  • Index 2 soils: Apply fertiliser at maintenance levels and 9 units of P and 24 units of K to build soil reserves (3 bags of 18:6:12)
  • Index 3 soils: Apply fertiliser at maintenance levels and 18 units of P and 48 units of K to build soil reserves (4.5 bags of 18:6:12).