While grass growth rates were lower than normal during much of April and May, crops have bulked up significantly over the last fortnight. Making silage is a trade-off between quality and bulk. Most crops are only beginning to head out now, so silage quality should be good. If left until after heading, there will be more bulk but DMD% will drop.

While the weather over the last few days has been good, the forecast for the coming week is more mixed, but there will still be chances to get silage cut in most places. Silage left in 10ft swarths for 24 hours should wilt to 30% dry matter. Grass in larger swaths takes much longer to wilt.

The target dry matter is 23 to 30%. There is no advantage to wilting grass any higher than 30% dry matter. Sugar levels are highest when silage is mowed on sunny afternoons. If in doubt, get sugars tested in Teagasc offices or feed merchants. The target is greater than 3%. Additives are not necessary in most situations, unless sugar levels are below 2% and weather is poor. In such situations, acids and molasses are better than innoculants. Nitrates are the other thing to look out for.

Normally, nitrogen is used up at a rate of two units per day in good growing conditions. Where nitrates are high, wilting to 30% dry matter will overcome any effects.

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