Average grass growth rates in Leinster have fallen to 56kg per day. Grass is growing at a rate of 58kg per day in Connacht and 60kg per day in Munster, while it is still at 67kg per day in Ulster.

Each of these growth rates shows a significant drop in growth compared with last week and, with the exception of Ulster, growth rates are probably less than demand on the majority of farms, as most farmers have land out for second-cut silage or reseeding.

The cause is a big reduction in rainfall compared with usual levels. Many farms have only had a few millimetres of rain over the past four weeks. And even those that got the benefit of thunderstorms two weeks ago are burning up now too.

Looking at the weather forecast, what rain that falls over the next two days will be it for the next 10 or 12 days. Temperatures are set to increase again too.

Warning

This is a warning to farmers to be conservative about grass. It’s time to park up the mowers and toppers. Mowing reduces growth rate and, while it cleans up swards, grass is too slow to come back after mowing. It’s better to have grass in paddocks that doesn’t look very nice, than to not have grass at all.

A bit like in spring, it’s important not to let average farm cover run down too low. The lowest I would like to see average farm cover is at 500kg/ha. For a farm stocked at three cows/ha, this is a cover of 166kg per cow, and for a farm stocked at four cows/ha, this is a cover per cow of 125kg, which is very low.

But not going lower than this is important, as doing so will reduce subsequent growth and delay recovery when the rain does come.

Reducing demand

Reducing the demand will be a key plank of action on most farms. This can be done by increasing the area available to cows. Is there ground closed for second-cut silage that could be grazed? It makes more sense to graze this than feed out conserved silage.

The other way to reduce demand is to feed extra supplement. Ration, straights and silage are all options. In terms of straights, soya hulls or palm kernel expeller are good options in a drought, but I’m hearing that prices of these have gone up to over €200/t, while ration will cost over €260/t.

Where good-quality bales are available, they can be fed back. You should give bales at least three weeks between making and feeding back out to ensure it has preserved and the pH has stabilised.

Use data to aid decisions about how much supplement to feed. If growth is less than demand and you are at a low average farm cover (approaching 500kg/ha) then the difference between growth and demand divided by stocking rate is how much supplement you need to feed.

For example, if the farm is stocked at 3.5 cows/ha, so demand is 60kg, but let’s say growth is 45kg/day. In this case, growth is 15kg less than demand. Dividing 15kg by the stocking rate means 4.3kg of supplement per cow should be fed to hold average farm cover where it is.

However, this presumes too things. Firstly, that growth is going to remain the same. If it rises or falls, average farm cover will track it. Secondly, farms that have a high average farm cover now can afford to let it fall before spending money on supplement it doesn’t really need.

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