The average grass growth across the country is around 56kg/day. This is from measurements taken over the past seven days.

Of course, a lot depends on when the previous measurement was taken. Heavy rain last Tuesday and Wednesday made a big difference to growth rates on land that was dried out.

On the other side, some farms, particularly in the southwest, got very heavy rain, in excess of 50mm in some places, and this caused its own problems with utilisation.

As the week progresses and when more measurements are taken capturing the period of growth since the rain, I would expect to see that grass growth rates are averaging around 70kg at the moment.

How to work out herd demand

This should be more than enough to satisfy herd demand at present.

Work out demand by multiplying how much grass the cows are eating by the current stocking rate.

For example, 100 cows eating 16kg of grass and stocked at 3 cows/ha is a demand of 48kg/day.

If growth rate is above this, the farm is generating surplus grass.

Average farm cover

The next thing to watch is average farm cover. At this stage in the year, this should be in or around 180kg/cow.

Much lower than this and grass could be getting scarce if growth slows down.

If cover per cow is much higher, then there will be too much grass on the farm, meaning pre-grazing yields will be high and, by definition, grass quality will be poor.

This will adversely affect milk protein composition. With milk yields tailing off, the key over the next few months will be to try to capture as much milk solids as possible by increasing protein percentage.

Drop in milk volume

While milk volume will drop, there is the potential to keep the actual milk receipts similar to last month if fat and protein percentage increases.

There is a natural increase in protein percent as we go through lactation, but more of this could be captured by giving cows better-quality grass.

It is too early to be building up covers for the autumn yet; two weeks time is time enough to be doing this.

Pre-grazing yield

So for the moment, concentrate on giving cows grass of a pre-grazing yield of between 1,300kg and 1,600kg/ha.

Keep rotation length at 20 to 21 days and allocate enough grass for three grazings.

Avoid high stocking rates at this time of year. A high stocking rate necessitates a high pre-grazing yield and this is detrimental to quality.

Ideal stocking rate

The ideal stocking rate is around 3.5 cows/ha.

This equates to a grass demand of 60kg/day and on a 21-day round length means that pre-grazing yield should be 1,250kg/ha.

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