Incorporating clover in grassland, Reducing chemical fertiliser and increasing milk solids.
Nicholas McKenna, Dairy Specialist reports from the recent Teagasc National Dairy Conference 2020, to highlight some of the main points made by John McNamara, Grassland farmer of the year 2018 and Michael Egan Grassland researcher, including the establishment of white clover in the grass sward
The discussion centred on how and why John uses white clover on his farm, while Michael looked at the overall benefits and challenges of clover inclusion and the options available to farmers who want to use it more often.
John McNamara’s farming system
Farming in the parish of Knockainey, Co. Limerick, John runs a simple and efficient system milking 250 cows. He has been growing the business over the last 20 years, stressing, that it would not have been possible without the high level of grass he has been growing and utilising.
John puts a lot of faith in Pasturebase Ireland and says it has really helped him to improve his grassland management over the years “learning how to grow it, manage it and utilise it”. John walks the farm weekly, takes a grass measurement on his phone using the PBI phone app and therefore all his decisions are “proactive instead of reactive”
John has been growing 15 tonne/DM/ha for the last few seasons and utilising 90% of this, he has placed an emphasis on really good grazing infrastructure having focused on:
- Square blocks.
- Multiple gaps into paddocks.
- Back fencing.
- Water trough position and access.
Why use white clover
John has begun to establish clover on the farm, with a target to achieve at least 20% clover content in the sward, the reasons for the inclusion of white clover on his farm according to John is to:
- Improve the quality of herbage (more palatable).
- Reduce chemical fertilisers.
- Increase milk solids by 10-15kgs/cow/year.
In terms of fertiliser, the grassland farmer of the year expects to make a saving in the summer and into the autumn months. John hopes to be able to reduce fertiliser on clover paddocks by half during this time, whilst growing as much grass, which is more palatable and will drive milk production.
He is also using low emission slurry spreading (LESS), and he targets most his slurry in the spring time which again reduces the need for chemical fertilisers. “I am using LESS in the spring and clover in the summer & autumn to reduce chemical fertiliser by 23-30 kg N/ha”
Michael Egan, grassland researcher, went on to discuss methods available to farmers who want to increase the levels of clover in their paddocks, he outlined the 2 main methods:
- Full reseed, using 1.5 kg/ha of clover seed. - Need good soil fertility and grazing management after seeding to ensure establishment and persistence of the clover plant.
- Over-sowing, which can be successful but a bit more challenging. Can be broadcast with a fertiliser spreader (tricky & success is generally lower). Guttler/stitch sowing machine (Needs to be done earlier in the year when soil moisture is higher)
For over-sowing the rate of seed application needs to be higher (2-2.5 kg/ha), Mike emphasises that putting the seed out is the easy part of the operation, but there are many other factors which need to be addressed:
- Excellent soil fertility is needed.
- Post seeding grassland management needs to be excellent to ensure sward is grazed correctly and looked after.
- Treat over-sowing like a full reseed, keep grazing covers low (1,100 kg DM/ha) for at least 3 grazings.
- Graze to 4cm to allow light to reach the clover plant.
- Don’t close clover paddocks first, close toward end of closing period as this leaves a lighter grass cover over the winter.
John has carried out clover establishment in all of the above ways in 2020, pointing out that it is early yet to see the full differences, but he believes the full reseed option is the best way to ensure establishment and persistence within the sward.
John is a firm believer that clover usage on his farm will have great benefits, but it is not an overnight success, it is a journey on which he needs to increase his knowledge and adapt his management techniques in order to see the full benefits of clover inclusion.
Top tips for clover establishment
To close the session both John and Mike were asked their top tips for successful establishment of clover in grassland. John emphasised the following:
- Start grass measuring, it’s vital to understand and measure how clover performs in a sward.
- Get soil fertility correct before you even begin to establish large amounts of clover.
Michael’s top tips:
- Soil sample the farm and use the fertility report to target paddocks for clover establishment and reseeding.
- Put a plan in place for the next 3-5 years.
- Treat every paddock on the farm on an individual basis, both when applying fertilisers and when deciding what method to use when sowing clover.
Catch up on all the recordings from the Virtual Dairy Conference here https://www.teagasc.ie/news--events/daily/dairy/2020-virtual-dairy-conference---overall-summary.php