Grass dry matters are low and cows are moving through areas quickly, with soiled grass at gaps into paddocks and around wet areas reducing utilisation. Clean-outs are poor and from speaking to milk lorry drivers, cows have dropped yield on most farms.

That’s the reality of an Irish summer with unpredictable weather. A week ago farmers were glad to see the rain and now they have enough of it.

While farmers can’t influence the weather, there are things that you can do on the farm to improve clean-outs, even in wet weather.

The first thing is to do with allocation. When ground is sticky, you should go back to a 12-hour grass allocation. This will improve the clean-out once the right amount of grass is allocated.

To work out the correct allocation, multiply the number of animals in the herd by their expected grass allowance. For cows, this is probably around 18kg/head of grass dry matter – less if supplement is being fed.

This will give you how much grass dry matter you need to allocate, for example 100 cows times 18kg is equal to 1,800kg.

The next thing is to work out the cover that is in the field. Let’s presume it is 1,500kg/ha. To work out the area, divide 1,800kg by 1,500kg/ha. In this example, it is 1.2ha/day or 0.6ha per milking.

In wet weather, it is easier to graze lighter covers as less grass will be walked in.

Some farmers are feeding silage to build up grass covers. When ground conditions are wet and it is harder to build up covers anyway, it might make more sense to hold off on silage for a few days until the weather improves and then feed a little extra then to make it up.

High supplementation rates don’t help with clean-out even when conditions are good. It is no harm to feed an extra kilo or two of meal during periods of high rainfall to help keep intakes up and as an aid in the prevention of grass tetany, which is a high risk at the moment.

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