GrowthWatch: Building autumn covers firmly in sight

By Teagasc’s Seán Cummins and James Fitzgerald

Extending the number of grazing days beef cattle spend at grass each year is a key component of profitable beef production systems.

As we approach mid-August, it’s worth remembering a number of key targets in order to ensure the beef farm is set up to extend the grazing season and to make the best use of grass between now and housing.

Remember the mid-August average farm cover target is 500kg DM/ha for an enterprise stocked at 2.5LU/ha. This climbs to 750kg DM/ha on September 1 and grows further to 1,000-1,100kg DM/ha by mid-September.

Ideally, the farm should have an average farm cover of 1,000kg DM/ha by October 1 and the target should be to have 60% of the grazing area closed by November 1, with housing to occur at an average farm cover of 550-600kg DM/ha.

In addition, the rotation length also needs to be adjusted outwards as the year progresses, as detailed in the below table for a stocking rate of 2.5LU/ha.

Shane Cranny, Myshall, Co. Carlow:
  • Growth: 49kg DM/ha/day;
  • Demand: 47kg DM/ha/day;
  • Average farm cover: 800kg DM/ha/day;
  • Stocking rate: 2.24LU/ha.

Growth and demand remained relatively matched last week at 49kg and 47kg, respectively. I made the decision in mid-July to close some of the grazing ground for a light cut of silage and we took advantage of the weather over the past weekend and took this out.

We’ve yet to introduce meal to the 22 month old steers and I hope to draft a batch off grass before meal is introduced.

These will be early-maturing steers and some of the stockier-type British Friesians, which have done well since turnout in February.

In terms of fertiliser, the ground which was cut over the weekend received two bags of 18:6:12 per acre yesterday and I’m following the cattle with a bag of CAN to help build covers going into the back end of the year.

Some of the paddocks are also low in potassium, so 2t of MOP will be applied over the coming weeks to help build fertility in these paddocks.

Peter Byrne, Castledermot, Co. Kildare:
  • Growth: 55kg DM/ha/day;
  • Demand: 38kg DM/ha/day;
  • Average farm cover: 713kg DM/ha/day;
  • Stocking rate: 2.68LU/ha.


Going off the results of my last grass measure on Monday, the demand for grass is 17kg DM/ha/day less than the growth rate for the last week (38kg DM/ha/day vs 55kg DM/ha/day).

This is the scenario I want to be in at this time of year as it is time to start building up a bank of grass on the farm that I can graze in the back end of the year when growth has stopped.

I am aiming for an average farm cover of 1,000-1,100kg DM/ha by this time next month, so – to achieve this – I will need the grass growth rate to stay 10kg DM/ha/day ahead of demand between now and then.

To help ensure that growth rates stay 10kg DM/ha/day ahead of demand, I am spreading the last round of fertiliser as I graze (23 units of nitrogen) which should boost on growth.

I will be selecting autumn 2018-born bullocks and spring 2019-born heifers in the coming days that will begin to get fed concentrates for finishing.

This should help to reduce their appetite for grass, while getting a proper finish on them before bringing them to beef later in the autumn.