Futureproofing the business with clover

With almost 60% of the milking platform with high clover contents, Cork farmer Tom O’Connell is really beginning to see the benefits of it. Last year, the fields with good clover contents got no chemical nitrogen from after March and grew the same as the fields with no clover but getting chemical nitrogen.

A total of 184kg N/ha was spread across the milking platform last year, with soiled water targeted at the clover fields after every second grazing.

Tom’s clover journey began in 2019 when he started experimenting with oversowing.

“I was looking at the trial work from Moorepark and I could see the benefits, even before the price of nitrogen went up. They were getting extra milk solids from the cows, spreading less nitrogen and making more profit. I could also see the way regulations were going and we would have been heavy enough users of nitrogen so I felt clover was a way for us to future-proof the business,” Tom says.

He says that the four fields he tried in 2019 produced mixed results and, importantly, not enough clover to reduce chemical nitrogen rates. But he kept at it, oversowing and reseeding clover every year since with good results.

He has oversown with a quad and pellet spreader, tractor and fertiliser spreader and a Moore Unidrill.

Tom’s preference at this stage is for the Moore drill because he says if it gets very dry after sowing, the seeds that are broadcast may struggle whereas they’ve a better chance if sown with the drill.

A Teagasc clover walk was held on the farm on Monday and the success of the oversowing was clear to see with upwards of 20% clover content in the fields that were reseeded or oversown.

On one field, Tom went in and broadcast the clover seeds at 2.5kg/acre using a quad and spinner when there was a grass cover of 800kg DM/ha in the field.

He grazed it with the cows the following day and then spread soiled water after grazing. This paddock was then grazed at light covers less than 1,000kg DM/ha for the rest of the season.

The advice from the Teagasc experts Deirdre Hennessy and John Maher was clear – clover is a picky plant and it needs good soil fertility if it is to survive. Deirdre says a soil pH of 6.5 to 6.8 is optimum with a minimum of index three for phosphorus and potassium.

She says that only fields with a high percentage of perennial ryegrass and a low percentage of weeds should be oversown with clover. If fields have that, they should be corrected this year and then oversow next year.

Tom says that after initially aiming to get over 50% of the farm with clover, he is now keen to keep going and get clover in all of the farm. However, he says the rate of oversowing will decrease and he will probably just reseed one field and oversow one field each year.

“It can be a big challenge to send cows into the oversown paddocks at low covers, especially when growth rates are high and if you have a couple of paddocks oversown. You could be nearly a week going through them and then when you’re done the first one is nearly fit to be grazed again. I find that it can be hard on cows, going into these low covers for that amount of time so I think only oversowing one or two paddocks per year is enough,” he says.

The O’Connells are milking 325 cows on a 192ha farm at Iniscarra, just west of Cork city.

With 91ha in the milking platform the stocking rate is 3.5 cows/ha but the overall stocking rate is 2.4 cows/ha. Performance is excellent with the farm growing 13.4t DM/ha last year and the herd selling 521kg MS/cow last year although the meal feeding was high with 1.19t of meal per cow, plus an additional 190kg of palm kernel fed during the drought. The herd is Jersey crossbred with an EBI of €224 and a six-week calving rate of 86% with a replacement rate of 21%.

Tom says he likes the medium-sized cow. “The cows have a lot of walking to do, so we like the medium-sized cow and will be trying to hold on to it, so we put a lot of emphasis on the maintenance value when picking bulls. I want a robust cow that’s easy to manage.”

In terms of managing grass this spring, he says February was a “breeze” but March was very tricky; on-off grazing every morning and evening almost every day.

However, he still managed to keep grass in the diet and this is probably standing to the herd now in that the protein is reasonably good at 3.43%, fat is 4.76% and they are milking 27l per cow or 2.27kg MS/cow.

Opening average farm cover was high at 1,200kg and this has been run down to 443kg/ha today or 214kg per cow. On Monday, he had seven grazings left in the first rotation but was alternating between first and second rotation grass on a day/night basis. He says he finds this easier on cows’ stomachs as second-rotation grass can be very lush.

He has 20 units/acre spread across the farm to date but is planning now on blanket spreading all paddocks with 30 units/acre of protected urea plus sulphur.

The importance of sulphur for both clover and grass and silage was also highlighted at the walk with Teagasc’s Stuart Childs saying that grazing ground needs 16 units/acre of sulphur per year and silage ground needs 16 units/acre of sulphur per cut.

Tom planted some red clover on the outfarm last April and this is currently being grazed by the maiden heifers.

The plan then is to apply 2,500 gallons/acre of cattle slurry and cut with the main first-cut silage at the end of May, followed by a second cut and then either a third cut or zero graze at the back end of the year.

Farmers were advised to use medium-leafed clover varieties and high-quality grass varieties, with at least three stars for utilisation when reseeding.

The clover varieties Tom has used are Chieftan, Crusader, Coolfin and Dublin.