While weather woes continue across the country, even the thoughts of grazing silage ground – never mind trying to get slurry and fertiliser applied – seems like an unrealistic task at this point in time in some parts.

Speaking at the recent Teagasc Green Acres Calf to Beef Programme farm walk – which was hosted by Co. Carlow-based farmer Shane Cranny – programme manager Alan Dillon had some timely advice in relation to the situation on some farms across the country.

“The most important advice I can give is to do a fodder budget and be sure there is enough silage in the yard to last three-to-four weeks; err on the side of caution when it comes to silage quantity in the yard,” he explained.

However, once we move out of this period of wet, windy and cold weather – which will hopefully happen sooner rather than later – farmers will have a number of questions to ask themselves:

  • How much silage do I need?
  • Where will I cut it?
  • When will I cut it?

However, as farmers across the country will experience a later turnout date than originally planned, Alan noted that farmers will have to “cut their cloth to measure”.

“We might not hit all our targets of getting silage ground grazed off by April 1, so we have to adjust plans. But, the most important thing is to make good-quality silage. If you are in this type of system, there is no room for bad-quality silage.

“If we look at 75% dry matter digestibility (DMD) silage – silage which is cut on May 20, we would expect a live weight gain of 0.83kg/day – which is not far off good-quality grass.

“If you can get that kind of a weight gain indoors from silage only, you are on a winner straight away,” he added.

“You can see when you move back down towards the start of June, you are back to 70% DMD silage and 0.66kg/day, and with 65% DMD silage (June 15) – that’s 0.5kg/day.

“With 60% DMD silage – that’s the end of June, so you are looking at 0.3kg/day,” he said. “The whole reason for having top-quality silage is to reduce meal intake; if you have low-quality silage, your meal bill goes up.”

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Continuing, he said: “An important message from this year is that the silage that you are feeding over the winter could be half the diet for the year.

“So, if you are feeding poor-quality silage only, you are spending half the year with an animal gaining no weight.”

Slurry and fertiliser requirements

When it comes to supplying adequate nutrients for silage, farmers should aim to make the best use of slurry; application rates of 3,000 gallons per acre are advised.

Where slurry is used to bolster nutrients, a time lag of five-to-seven days should be applied between slurry and artificial fertiliser applications to reduce the risk of nutrient losses.

“When spreading slurry, take account of the dry matter percentage of the slurry and the amount of concentrate being fed.

“If you are spreading slurry from a shed where a lot meal was fed, typically it’s going to have a potassium (K) content of 42 units per 1,000 gallons. If you take a shed where no concentrates were fed over the winter, the K content in that slurry is down to 30 units per 1,000 gallons.

“Farmers need to top that up with a bit of extra K from chemical fertiliser if you are putting out that type of slurry,” Alan explained.

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Touching on fertilser requirements, Alan said: “If you take a relatively good soil at index 3, all silage crops need 100 units of nitrogen (N) per acre. We want about 16 units of phosphorus (P) er acre and 100 units of K per acre.

“But, slurry will provide a lot of the K. Typically slurry will give 5-5-30 – ballpark. So, you have to work that into your system.

“We say typically go with 3,000 gallons of slurry per acre – get that out on ideally grazed-off ground but, saying that, we have more options with trailing shoes and dribble bars etc. So, you can go into something with a bit of a cover on it.

“On an index three soil, three bags/ac of 16-6-20 and 1.3 bags/ac of protected urea – if there is no slurry. With 3,000 gallons of cattle slurry, we need 1.75 bags/ac of protected urea.

“When using a dribble bar or trailing shoe, the N content in the slurry increases, so farmers need to take all these factors into account. The most important thing is, no matter what your stocking rate is, you need to feed that silage crop with the required nutrients.”

Teagasc’s Kevin Brennan also spoke about the importance of getting soil fertility right and the role of protected urea.

“If we want to reduce ammonia emissions, we all have to zone in on protected urea – which can be spread all year round – and the importance of it; the more people that use it, the better it is for us on a global scale.

“It has the ability to reduce ammonia and greenhouse gas (GHG) emissions by over 70%. When you are buying it in the co-op, make sure it has NBPT in it – if it doesn’t have that it’s not protected urea.”