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This year, Teagasc is changing how it evaluates grass varieties with the introduction of grazing cattle on varieties under test as part of the evaluation process. It is a positive step in the right direction. We need to get more plant stress (low rainfall, cattle walking) on varieties to replicate what is happening on Irish farms.
New varieties
We understand this week the new Department of Agriculture Recommended Grass Variety list will be officially released for 2017. Figures published in the Goldcrop catalogue last week show there are four new varieties on this year’s list – Aberwolf, Fintona, Aberclyde and Meiduno. Three are intermediate varieties and one late-heading variety (Meiduno).
When ranked on pasture profit index (PPI), seven of the top 10 varieties are intermediate varieties. Why? A good proportion of the PPI weighting is on spring growth and quality. Hence, the intermediates that head earlier in the season get better values for spring and this pushes them up the PPI ranking. Varieties with good spring yield such as Abermagic and Aberwolf, which also have good quality figures, shoot up the list and hence they are numbers two and six, respectively, on the PPI ranking list. The recommended list ranges from a value of €206 for Aberclyde down to an overall value of €23 for Tyrella.
There are some anomolies with these PPI figures and commercial farm experience and previous research. Grass trials at Moorepark suggest that late-heading varieties are better for midseason grass quality and our experience of Aberwolf and Abermagic, as described previously on these pages, would suggest that both react poorly when stressed due to drought, etc. However, recommended lists still have better information than those with no Irish measurements.
Oak Park Carlow
Teagasc has a grass and clover breeding centre at Teagasc Oak Park in Carlow. Since 2013, Goldcrop is the Teagasc partner with responsibilty for seed propagation, marketing and wholesale distribution of all new Teagasc-bred cultivars. For the 15 years previous to this, DLF Trifolium was Teagasc’s commercial partner. The main focus of the Teagasc breeding programme is to focus on trait improvements important to Irish farmers.
The scale of investment and workload in grass breeding taken on by Teagasc researcher Pat Conaghan and his team at Teagasc Oak Park has to be seen to be believed. Over 50ha are taken up with sowing new grass varieties and monitoring the yield growth, quality, etc.
Remember, the grass plant is wind pollinated, so test plots of varieties are grown surrounded by a crop of oats that is taller than the grass plant and hence helps prevent grass seeds moving between the grass plots. Clover, on the other hand, is pollinated by bees so it has to be pollinated in tunnels. Each year, Oak Park buys in a commercial bumble bee hive to pollinate the plants.
Oak Park evaluates about 3,000 plots per year and this year, for the first time, Teagasc is introducing cattle to get a handle on the grazing evaluation. Previously, it had sheep grazing clover plots but that was the extent of the impact of animals in the testing procedure. The thinking is that some varieties will perform better and worse as the grass plants are walked on by cattle in wet and dry weather.
Goldcrop partnership with Teagasc
Last Thursday, Goldcrop hosted a grassland conference group at Teagasc Oak Park. Dave Barry, Goldcrop general manager for grass seeds, was one of the first to speak. He said: “For Goldcrop, our access to material and partnership with Teagasc is very important to us. The opportunity came in 2013 to be the preferred candidate and we handle producing the seed and marketing the varieties across the world.”
Barry explained the history behind Goldcrop and how tonnages sold vary from year to year (Figure 2).
He said: “In terms of tonnage, 2010 was a huge year for grass seed with brilliant weather following a disastrous 2008/9. In 2012, it rained all summer. On average, about 3.6m tonnes of grass seed are sold in Ireland. For the trade, it’s a fine balance between getting enough seed stock and not getting submerged in grass seed.”
In Ireland, about 3.6m hectares of 104,400ha are reseeded each year – about 2.9%. Barry was keen to point out that livestock numbers are going up in Ireland since 2010 and extra fodder is needed (Figure 1).
He said: “The dairy industry expects a 30% increase in dairy production over coming years with a 33% increase in cow numbers from 2010 to 2016 when an estimated 1.34m dairy cows produced milk in Republic of Ireland.
‘‘Extra fodder is needed. Irrespective of what you want, all varieties chosen should be from either the recommended list of Northern Ireland or the Republic. For each variety on the recommended list, on average six varieties have failed to make the cut.”
All information presented in the PPI is from mechanically cut plots that are used to predict the performance under actual grazing. No information from animal grazing trials is included in the PPI. Seven of the top 10 varieties are intermediate varieties (earlier heading date than the late varieties). When you look at the various categories measured on the PPI you can rank the varieties in the different categories. Table 2 shows the top 10 varieties ranked on spring growth, autumn growth, total yield, silage yield and quality.
No location difference
“When we look at the figures, our top 20 farms in 2016 grew more than 16t of grass dry matter. This was split on average at 13.5t used for grazing and 2.7t of silage. One of these farms was in south Mayo. These figures show that no matter what part of Ireland you are growing grass in, achieving high volumes of grass grown is achievable with good management.”
When questioned on varieties for zero grazing, Michael O’Donovan said: “No different to a good grazing sward with good digestibility. If these farmers put more money into soil fertility and infrastructure it might be more valuable.”
New fodder rape variety
Goldcrop has a new fodder rape variety called Gorilla. It is a hybrid variety with high yield and good regrowth potential. According to Goldcrop’s Pat Cashman it is a darker green leafy type of crop, of medium height with good standing ability. Results from UK trials show yield to be about 10% over the 4.25t of dry matter potential at 12% dry matter. When sown early (May), it can produce a first crop in August and then has regrowth potential to achieve a second crop in November/December. Effectively, it is managed as per fodder rape and is sown from April to August at a seeding rate of 3.6kg to 4.5 kg/acre depending on conditions with crop fed out from June to February.
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