How to improve output from cows grazing in poor conditions

To improve the utilisation of grazed grass this year, the focus must be on the first two grazing rounds.

Poor ground conditions from February to April, with incorrect management, can lead to just 50-60% utilisation – and reduce grass growth for the rest of the season.

See also: How to manage surplus grass at spring turnout

The biggest influence on grazing efficiency is in spring, says Ireland-based consultant Andre van Barneveld, from Graise Consultancy.

“Utilisation depends more on conditions than sward species,” he says.

“People get hung up on targets from their spring rotation planner [SRP] and aim to graze 30% of the farm in February. But it is knowing where to compromise,” he explains.

“A paddock grazed in good conditions on 10 March will be ready to regraze sooner than one that is poached on 10 February, as recovery will take too long, and this has a big impact on final grass yield and utilisation.”

Grass plant

Andre’s rule of thumb for the severity of poaching caused by poor grazing conditions is whether the grass plant has been pushed down into the soil without dislodging the root system. “In this case, the grass plant can re-establish itself,” he says.

“But where grass has been trod and buried in the soil – or the leaves broken off and starting to decompose – it won’t be available to be consumed by the cow in the second grazing round. In this case, both utilisation and pasture growth have been compromised.”

The risk of grazing in wet conditions is not just about poaching. Feeding silage or concentrates (to maintain milk yield and profit) leads to higher costs through overcompensating, he points out.

This is because feeding supplements reduces the cow’s appetite to graze efficiently, and instead, she wastes more grass.

Furthermore, when pasture is in ample supply, higher rates of supplement feeding become uneconomic due to substitution.

Utilisation target

While it is possible to hit a utilisation figure of 90% in good, dry conditions, Andre points out the annual target for this grazing KPI is 85%. This optimises pasture utilisation, through balancing efficiency with maintaining pasture regrowth.

To avoid sward damage at the start of the grazing season, he says the basics are planning for bad times such as flooding, identifying early turnout paddocks and having a good network of tracks and troughs.

Thereafter, a flexible mindset and the confidence to adapt management when faced with bad weather and poor grazing conditions are key to success.

Andre suggests grazing lower covers when conditions are poor, going in at 2,500kg of dry matter (DM)/ha, giving cows a bigger area, and leaving paddocks at the correct residual.

Measuring and feed budgeting are crucial. “It is hard to allocate the correct amount of grass if you don’t know your cover. Ideally, measure grass one to two weeks before the first grazing so you can do a budget and SRP,” he says.

A good network of tracks is a basic essential to access grazing in poor conditions © MAG/Shirley Macmillan

On-off grazing

“Look at on-off grazing where cows can get 80% of their daily DM intake in two lots of three-hour grazing,” Andre explains.

“But don’t get hung up about water troughs – if cows are only out for three hours, grass will be well in excess of 80% water, and it is temporary.”

Some herds with housing for only half their cows might split the herd and put half out to graze during the day, and half at night, according to ground conditions.

“There are farms still operating with just one or two gateways, which is restricting. People need to think flexibly when it comes to access points: cut the fence, add a handle and go into paddocks at several points – put in four gateways.”

Correcting poaching

Once cows leave paddocks, Andre says it is important to assess the damage.

“Don’t write it off without going into the paddock to take a proper look,” he stresses.

Depending on soil type, he says a shower of rain can rectify a light degree of soil damage. In other cases, it will be corrected in the next grazing round.

In good conditions, cows tread the high points and even out the soil surface, as long as pre-grazing covers are no greater than 2,800kg DM/ha.

He cautions against using a roller because it removes air as it compacts the soil, although a spike roller (or harrows) will aerate as it levels the soil.