Clover: The last few weeks appear to have been good for clover. Drier conditions reduced grass growth which enabled clover to better compete in the sward.
This is the time of year when clover comes into its own. It’s a delicate plant that needs to be minded.
Letting covers go too strong before grazing or cutting will cause the clover to be shaded out.
Tight grazing at low covers allows plenty of light down to the base of the grass/clover sward.
To get value from clover, it needs to be present in high quantities – averaging around 20% for the year. This means that it needs to be close to double that now, at around 35% to 40% clover in the sward. In effect, this looks like a huge amount of clover and few fields ever hit this benchmark.
A lot of farmers think they have clover, but if it isn’t present in the quantities that would facilitate a reduction in chemical nitrogen use, is it really useful? Teagasc advice is that where clover content is greater than 25%, nitrogen use can be reduced, as the clover should be fixing the nitrogen that is normally supplied in the chemical form.
Fertiliser: Spreading less nitrogen on fields with lower clover content won’t automatically boost clover content, but it will reduce grass growth rates. You need to increase clover content through reseeding or oversowing and then reduce chemical nitrogen.
On grass/clover reseeds sown this year, it should be possible to reduce chemical N from now on.
However, not spreading N does not mean not spreading fertiliser.
Clover needs phosphorus and potash and because it has a small root mass close to the surface compared to ryegrass, it has to compete for those nutrients. Spreading additional P and K is an essential part of improving and maintaining clover in swards. Over-sowing continues to be hit and miss and it is probably too late in the year for that now anyway.
Grass: As most of the country got upwards of 20mm of rain over the past week, the soil moisture deficit that was present has abated. The grass situation improved instantly, as most fields were still green even though growth had slowed greatly.
However, it will still take a while for farms that were very low in average farm cover (AFC) to bounce back. In these situations, extra supplement will have to be fed for longer. It’s important to keep feeding until such time as the AFC has returned to normal. This is when AFC per cow is above 160-170kg and growth rate is greater than demand, with normal levels of supplement being fed.
Equally, those now back at target grass levels need to drop any extra supplement as soon as possible. It makes no sense to be feeding extra supplement now, only to be dealing with surplus grass in a week or 10 days’ time. Given the soil temperatures, soil moisture levels and the release of nitrogen, there will be a big growth bounce on farms that were badly affected. There is usually a good dividend in terms of grass growth after a dry spell. It could be an opportunity for some farms to take out paddocks for reseeding.