Grass growth rates are back 50% on this time last year – Teagasc

March grass growth rates are currently running 50% behind last year’s levels, according to Teagasc’s George Ramsbottom.

Teagasc’s PastureBase shows that the average grass growth rate on a number of dairy research and commercial farms is 15kg Dry Matter per hectare per day.

“Typically it would be expected to see growth rates of almost double this at 25-30kg DM/ha per day in late March, so that’s half of what we’d normally expect,” the Teagasc Dairy Specialist said.

“The reason for such low growth rates is the low temperatures – a key driver of grass growth in early spring.  Currently, temperatures are averaging 7 degrees Celcius on farms which is almost 2 degrees Celcius lower than normal.”

He said that due to a recent spate of poor weather, a number of farms have witnessed grass growth levels close to zero. And, as a result, farmers have been forced to dip into their fodder reserves.

“This is the reality of what is going on. Farmers are hoping that the weather will improve shortly.

“Due to grass shortage, dairy farmers are being forced to supplement their herd’s diet with silage and meal to try and maintain milk solids.

“This has resulted in on-farm costs being driven up on farms this spring,” he said.

The dairy specialist also said that the slower growth rates have resulted in lower grass covers for farmers starting the second round of grazing.

“At this stage, we should be seeing grass covers on the first grazed paddocks of 1,200kg DM/ha. In most cases we have only seen half of that, at 500-600kg DM/ha.

Grass cover of 1,200kg/ha (9-10cm).
Grass cover of 1,200kg/ha (9-10cm).

“Our advice to farmers is to keep Nitrogen spread in line with their annual fertiliser plan, and continue to supplement, while they wait for grass growth to catch up,” he said.

Teagasc also advises farmers to go back and look at the first grazed fields to decide if action needs to be taken.

‘Walk the farm. Pay particular attention to the covers on the early grazed paddocks.

“Firstly, maintain a rotation length over the whole of the grazing platform of at least 20 days.  Supplement with silage and meal to feed the cows adequately.

“When the recovery commences, phase out the silage feeding first and you should see an increase in grass intake by the cow and protein percent in the milk.

“Then as grass covers increase, reduce the amount of meal fed.

Thirdly, start to close up fields for silage.  The last thing we want to do is to sacrifice body condition of the dairy cows just before the breeding season begins,” Ramsbottom said.

Grazed paddocks are slow to regrow this spring.