The sharp spike in grass growth north of Dublin during the first half of May was great news for silage makers.

But it is causing significant problems for dairy and other livestock farmers seeking to get the best from their grazing swards at the present time.

Aaron Callan and his father Pat milk 350 cows, a mix of Montbeliarde and Montbeliarde/Holstein crosses, on their home farm at Philipstown, close to Dunleer in Co. Louth.

The herd is split into autumn- and spring-calving groups; approximately 30% of the cows calve down prior to Christmas.

The Callan herd is currently averaging just short of 8,000L/lactation, equating to 630kg of milk solids/cow.

Both Pat and Aaron are confirming that 2022 has been a tremendous for grass growth – so far. They took the decision to cut back somewhat on the levels of nitrogen (N) put out on to the silage ground back in the spring.

“Usually we put out three bags of N/ac on first cut ground; this year we cut that back to 2.5 bags,” Pat explained.

“We then decided to cut back the amount of nitrogen put out on second cut ground from 2.5 bags to 2 bags. But we have plenty of slurry available to us and we are genuinely making best use of it this year.

“The first cut was taken on May 10. Grass yields were excellent and we are now waiting to see what the quality of the actual silage will come in at,” he added.

“There’s no doubt that the weather has played its part in delivering bumper yields of grass, despite the fact that fertiliser usage is back. But we will have to see how the rest of the year plays out.”

Grassland management and grass growth

The Callans graze their entire grassland area with store lambs over the winter months.

Aaron added: “We have them off the land by the early part of January. But there is no doubt that lambs can help deliver very high quality grass regrowths during the early spring period.”

The Callans will soon know exactly how their first-cut silage will perform next winter, courtesy of an analysis that is due to be carried out over the coming days.

They are among the first Irish farmers to use the new Bio-Sil inoculant, which delivers a rapid pH drop directly after ensiling.

Bio-Sil’s Frank Foster was a recent visitor to the Callan farm. He was accompanied by Aonghus Giggins from Livestock Nutrition Solutions.

“A key attribute of Bio-Sil is the inoculant’s ability to deliver a fully fermented and stable silage within four weeks of ensiling,” Frank explained.

“A number of farmers throughout Ireland have used Bio-Sil this spring. On the back of this, our aim is to publish a review of first-cut silage analysis results for 2022 over the coming days.”

Aonghus Giggins highlighted the importance of farmers grass testing swards prior to their ensiling.

“Farmers might think that high forage nitrogen levels in grass directly prior to ensiling will not be an issue this year,” he explained.

“The fact is that Irish growing conditions are such, that high nitrogen levels in forage could always be an issue, irrespective of how much or how little nitrogen fertiliser is applied to growing crops.

“Given these services, grass testing prior to silage being made is always strongly advised.”