Grass breeders are becoming increasingly focused on grazing efficiency, which essentially measures how well different varieties are grazed out by livestock.
A study conducted by Teagasc over the past two grazing seasons measured residual covers across 30 perennial ryegrass varieties and found tetraploid grasses generally had better grazing efficiency.
According to Paul Flanagan, general manager of seed company DLF Ireland, these findings, coupled with research which shows that most tetraploids have better yields and sward quality than diploids, mean tetraploids will make up a larger proportion of grass seed mixtures in the future.
“On average, tetraploid varieties probably make up around 30-40% of mixtures across Ireland, but in most of our grazing mixes we are pushing for 60%,” he said at an event in Omagh earlier this month.
DLF has been conducting its own trials on four commercial dairy farms in Tyrone, Offaly, Waterford and Kerry since 2015. Grass yield, sward quality and grazing efficiency are the key factors being examined.
To date, the four farms have been using varieties that are already on the market, but the plan from this year onwards is to trial varieties which are yet to be independently tested and listed on Teagasc’s recommended list, the Pasture Profit Index (PPI).
Testing
Flanagan said that DLF uses data from its own research site in Waterford to select four to six varieties from a pool of around 1,500 to go forward for independent testing each year.
Grazing efficiency is becoming more important for grass seed companies as data from the Teagasc grazing study is to be included in the PPI from next year onwards.
“In our own trialling system we cut under a simulated grazing system so we know what the quality is, what the yield is and what it looks like, but what we don’t know is how a cow will interact with it and that’s what we want to find out on these farms,” Flanagan said.
This paddock was reseeded with a monoculture of the tetraploid Solas last year.
Monocultures, as opposed to mixtures of different varieties, are sown on the trial farms by DLF. “It is more for a research element, rather than advocating the sowing of monocultures. We should still be looking at mixtures because one variety may complement another variety very well,” Flanagan said.
Tyrone dairy farmer David Hunter is trialling grass varieties for DLF on his farm near Newtownstewart, Co Tyrone, and last year he reseeded two paddocks with straight tetraploids. One paddock was sown with Aspect and the other with Solas. Tetraploid swards can be less dense compared to diploids, and the paddock with Solas on the Hunter farm is particularly open. However, it was pointed out that this sward has had limited opportunity to tiller so far as it was only grazed once last year, and it carried a high cover over the winter.
Grazing
The Hunter farm grew 14.6t of dry matter per hectare (DM/ha) on average on the grazing platform last year, with the top two performing paddocks growing 18.8tDM/ha and 18.6tDM/ha.
Damian McAllister from DLF said the two highest-yielding paddocks on David’s farm were grazed 11 times last year, whereas all other paddocks were grazed 10 times.
“It shows that if you want to grow more grass, you have to graze more often. Don’t say ‘it’s not worth my while putting the cows out for only a day or two’ if there is wet weather forecast in a few days’ time,” he said.
David runs 85 cows in a block spring-calving system and is using cross-breeding with Holstein and Jersey genetics to a develop robust, low-maintenance herd that can produce milk from grazed grass.
Cows got to grass during the day in mid-February and this was the first year since David began dairying in 2012 that cows were at grass full-time before the beginning of March. Wet weather in early April meant cows had to be rehoused but they were back out at grass again after three days.
Read more
NZ-style dairy system in Co Tyrone
Commercial farms trialling grass varieties for DLF
Grass breeders are becoming increasingly focused on grazing efficiency, which essentially measures how well different varieties are grazed out by livestock.
A study conducted by Teagasc over the past two grazing seasons measured residual covers across 30 perennial ryegrass varieties and found tetraploid grasses generally had better grazing efficiency.
According to Paul Flanagan, general manager of seed company DLF Ireland, these findings, coupled with research which shows that most tetraploids have better yields and sward quality than diploids, mean tetraploids will make up a larger proportion of grass seed mixtures in the future.
“On average, tetraploid varieties probably make up around 30-40% of mixtures across Ireland, but in most of our grazing mixes we are pushing for 60%,” he said at an event in Omagh earlier this month.
DLF has been conducting its own trials on four commercial dairy farms in Tyrone, Offaly, Waterford and Kerry since 2015. Grass yield, sward quality and grazing efficiency are the key factors being examined.
To date, the four farms have been using varieties that are already on the market, but the plan from this year onwards is to trial varieties which are yet to be independently tested and listed on Teagasc’s recommended list, the Pasture Profit Index (PPI).
Testing
Flanagan said that DLF uses data from its own research site in Waterford to select four to six varieties from a pool of around 1,500 to go forward for independent testing each year.
Grazing efficiency is becoming more important for grass seed companies as data from the Teagasc grazing study is to be included in the PPI from next year onwards.
“In our own trialling system we cut under a simulated grazing system so we know what the quality is, what the yield is and what it looks like, but what we don’t know is how a cow will interact with it and that’s what we want to find out on these farms,” Flanagan said.
This paddock was reseeded with a monoculture of the tetraploid Solas last year.
Monocultures, as opposed to mixtures of different varieties, are sown on the trial farms by DLF. “It is more for a research element, rather than advocating the sowing of monocultures. We should still be looking at mixtures because one variety may complement another variety very well,” Flanagan said.
Tyrone dairy farmer David Hunter is trialling grass varieties for DLF on his farm near Newtownstewart, Co Tyrone, and last year he reseeded two paddocks with straight tetraploids. One paddock was sown with Aspect and the other with Solas. Tetraploid swards can be less dense compared to diploids, and the paddock with Solas on the Hunter farm is particularly open. However, it was pointed out that this sward has had limited opportunity to tiller so far as it was only grazed once last year, and it carried a high cover over the winter.
Grazing
The Hunter farm grew 14.6t of dry matter per hectare (DM/ha) on average on the grazing platform last year, with the top two performing paddocks growing 18.8tDM/ha and 18.6tDM/ha.
Damian McAllister from DLF said the two highest-yielding paddocks on David’s farm were grazed 11 times last year, whereas all other paddocks were grazed 10 times.
“It shows that if you want to grow more grass, you have to graze more often. Don’t say ‘it’s not worth my while putting the cows out for only a day or two’ if there is wet weather forecast in a few days’ time,” he said.
David runs 85 cows in a block spring-calving system and is using cross-breeding with Holstein and Jersey genetics to a develop robust, low-maintenance herd that can produce milk from grazed grass.
Cows got to grass during the day in mid-February and this was the first year since David began dairying in 2012 that cows were at grass full-time before the beginning of March. Wet weather in early April meant cows had to be rehoused but they were back out at grass again after three days.
Read more
NZ-style dairy system in Co Tyrone
Commercial farms trialling grass varieties for DLF
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