GrowthWatch: Grass moving ahead

By Teagasc’s Seán Cummins and James Fitzgerald 

Growth rates across the country have accelerated in recent days and some farms are now facing into a surplus of grass. However, on the other hand, some holdings are still experiencing lower growth rates than normal.

A small number of farms – particularly along the east coast – have experienced a slight decline in growth rates due to drier conditions.

The Teagasc PastureBase system shows that average growth rates were sitting at 57kg/ha/day in Ulster, 54kg/ha/day in Connacht, 51kg/ha/day in Leinster and 59kg/ha/day in Munster over the past seven days. The average farm cover stands at 787kg DM/ha.

Many farms are now finding that grass growth has exceeded demand and this will present an opportunity to take out surplus grass as high-quality bales.

By cutting these paddocks, you can ensure that a good clean out is achieved and add valuable feed to next winter’s reserves. If possible, slurry should be targeted at paddocks which were cut as silage.

As always, the above is very farm specific and any decisions should be made on the basis of a grass wedge. A grass wedge allows you to identify any surpluses or deficits easily and quickly. It’s seen by many as a vital tool for managing grazing throughout the year and particularly during periods of strong growth.

Ideally, farmers should target pre-grazing covers of 1,200-1,400kg/ha (dry matter), as it corresponds to the three-leaf grass growth stage; this target applies across a range of stocking rates.

Dramatic increases above these covers will lead to poorer grass utilisation and quality will suffer in the subsequent rotation(s).

While grazing, it is vitally important that farmers graze down to 4cm which will maintain quality in the sward for the next rotation. As always, the farm should be walked regularly to monitor growth rates.

The last of the silage ground was closed just over two weeks ago and the steers and calves are now well settled into their paddock grazing regime. Turnout was later than desired this spring for the older stock (March 25), but weather conditions just didn’t fall our way.

All of the ground received 46 units per acre of urea in late March and as paddocks are grazed, they’ll receive two bags of 18-6-12 per acre.

Calves, yearlings and 24-month steers are being given access to fresh grass daily. This serves two purposes. It ensures that the calves consume all of their allocated 1.35kg/day of an 18% crude protein concentrate, while it also allows for excellent clean outs to be achieved with the older stock.

After a slow start, growth has just passed demand and ‘magic’ day has arrived. As covers grow stronger over the coming weeks, I’ll start to take some of the heavier paddocks out in the form of surplus bales. Where surpluses will be removed, this ground will receive 2,000-2,500 gallons per acre of slurry to replace off-takes.

The grass growth rate has really taken off in the last couple of weeks following very low growth rates earlier in the spring. In order to keep grass from getting out of control I skipped the paddocks at the end of the first rotation and the start of the second and started grazing covers of 800-900kg DM/ha about 10 days ago.

The fields I skipped will be cut for silage in the next week to 10 days all going well. By the looks of things, with a demand for grass of 24kg DM/ha/day and growth rates of 70kg DM/ha/day and climbing fast, there will be more paddocks that will have to be cut for bales to keep grass under control.

All going well this should make super-quality silage that will keep cattle thriving in the sheds next winter with very little meal. 

I have an average of 63 units per acre of nitrogen spread so far this year. I will continue to follow the cattle around with either a half bag of protected urea / urea or 18-6-12 for the next round and base my fertiliser decisions on grass availability after that.