Dairy management: grass growth ready to take off

There has been a real touch of spring about the weather since Sunday. Gone is the cold, biting wind to be replaced by warm and sunny days.

The high pressure is set to last for a few more days before being replaced by low pressure and rain towards the weekend. Importantly, though, air temperatures are set to remain high, reaching 17°C at times.

I was on a Zoom discussion group meeting on Monday morning and about one third of the farmers in the group had started the second rotation, one third were about to start and the rest were up to a week away from starting it.

Discussion

At least that was their plan when they joined the call, but after the discussion it was pretty much agreed that staying in the first rotation for another 10 days or so will be too long.

The issue will be that pre-grazing yield will be too high, resulting in a drop in grass quality, which will in turn result in a drop in intakes and, subsequently, performance.

Oftentimes, this drop in performance is never noticed, because, in real terms, the cows should be increasing in performance as they come into peak.

For example, a herd could be increasing to say 2kg MS/day, but would be producing 2.1kg MS/day if on better-quality grass.

Recovery

The farmers in that discussion group were in two categories; those who got a good percentage grazed in February are flying it and on the second round; and those who got little or none of the farm grazed in February due to the bad weather are waiting for enough recovery on the first grazed paddocks to start grazing again.

Everyone needs to monitor the situation closely, as I would say every farm in the country will be growing more than demand this week.

The only cure is to skip over sections of the farm for silage. In most cases, this will be for long-term silage and can be fertilised as such.

In other cases, where there is a high stocking rate for example, the silage can only be for short term, so this should be cut and baled as soon as possible.

This is critical because if the demand is too high, say over 70kg/day, then if growth rates drop you will be eating into the average farm cover.

If the average farm cover is high, this will be OK. But where average farm cover is at 500kg to 600kg/ha, then you need to be careful not to let it go too low.

However, if the average farm cover is high at over 700kg/ha, as is the case for most, farmers can afford to let it drop and that is exactly what they should do.

The key thing is to take action depending on what is happening on your farm. Monitor grass growth and average farm cover carefully.

Read more

What direction is the Irish dairy cow going in?

Dairy Management: weaning calves, picking bulls and spreading fertiliser