Ground conditions are slowly improving and a growing number of farmers will be looking to slip some cattle back to grass by the end of March or early April.

Being able to graze cattle in late March takes planning, most of which should have started last autumn by closing off paddocks from all stock to provide grass for grazing in spring.

Outlined are 10 steps to managing cattle through spring grazing.

1 Walk the farm to gauge ground conditions and grass covers

If you aim to get cattle out to grass over the next two weeks, make sure to walk the farm in advance. Make a note of ground conditions and grass covers.

This gives a better handle on how many cattle can be grazed in late March and early April. Count up grazing days ahead for a potential group of stores.

Most farms around Northern Ireland will need 25 to 30 days in front of stock if target turnout is in late March. By the end of the first rotation, grass growth should be on the rise and matching cattle demand.

2 Plan out which fields to graze in the first rotation

Having walked the farm, use this info to plan out the first rotation. Some paddocks will be marginal in terms of ground condition and may need to be skipped until the end of the first rotation.

When ground conditions allow, focus on grazing as many heavier paddocks as possible. Likewise, target older swards.

Older grasses will be slower to regrow and less responsive to nitrogen. The earlier these swards can be grazed, the better. This gives more time for regrowth ahead of the next rotation.

Hold back a couple of drier paddocks for the second half of the first rotation. This way, if there is a period of heavy rain, cattle can be moved to these paddocks which will protect heavier swards.

3 Should I let cattle graze silage ground?

Normally, grazing silage ground in early spring is recommended. Grazing removes any dead matter in the sward, leaving a fresh base for growing silage.

Research trials has shown that grazing silage ground before closing can increase the feed value by as much as 5% D-Value.

But there is a cutoff point as grazing too late in April will reduce first-cut yields. The cut-off point depends on turnout date, target cutting date and the quality of silage the farmer wants.

For a high-quality forage around 70% D-Value, silage fields should be grazed and closed off by 10 April at the latest.

This allows silage to be safely harvested around 30 May, based on a nitrogen dressing of 100 units/acre for first-cut.

Silage can be cut a few days earlier, but rapid wilting will be critical to reduce nitrogen content in grass and give a stable fermentation.

If the aim is to cut silage around 20 to 25 May, fields needs to be grazed and closed off by the start of April.

4 Which stock should be grazed early?

Lighter stock will inflict less damage to swards and have a lower grazing demand, meaning grass covers will stretch further compared to grazing cows.

If replacement heifers are calved at 24 months, give priority to maiden heifers being retained for breeding. Early grazing will boost weight gain and increase service weight.

Next, turn out yearling stores destined for slaughter next winter. An early start will increase weight gain and housing weight by autumn, shortening the indoor finishing period. Cows can slip out to grass during April as grass growth picks up.

5 Gradually turn out cattle in small groups

Filter cattle out to grass in small groups. Allow these animals to settle for a few days before adding more animals to the group.

The evening before cattle go to grass, restrict silage intakes so animals are hungry the following morning when they go to grass.

6 Setting up paddocks

If the farm has a designated paddock system, then rotate cattle around the grazing block as normal, or when ground conditions allow.

But if you are setting up paddocks for the first time, then start big and reduce paddock size later in the season.

This gives more flexibility and cattle are less likely to run out of grass in April, which is a risk if paddocks are too small.

Splitting bigger fields in half is a good start and cuts down the problems with providing water to multiple paddocks. Move cattle to fresh grass at the start and end of the week as supplies allow.

When you get more experience of gauging covers, start to reduce paddock size with temporary fencing wires.

By using electric wires as a back fence, this will protect swards that have been grazed from poaching as cattle will look to nip off the regrowth.

7 Fertiliser

If turnout date is late March, getting 25 to 30 units/acre of bagged fertiliser out as soon as possible is important.

This will stimulate grass growth as soon as swards as grazed. Make sure to dress paddocks after grazing also.

Watery slurry can also be applied to paddocks after grazing, provided stock will not re-enter such paddocks for at least 18 to 20 days after spreading.

8 Be alert for grass tetany

If you are grazing freshly calved cows later this month, make sure animals are covered for magnesium to prevent tetany.

Avoid grazing paddocks that were heavily slurried in March. Slurry is high in potash, which inhibits magnesium uptake in grass.

Changeable weather, lower dry matter grass and lush grass are also risk factors for tetany.

9 Should I feed meal at grass?

If you are short of grass, feeding meal can help to stretch grazing covers and keep animals settled.

If freshly calved cows were fed 2kg to 3kg/day of meal indoors, offering concentrates for the first fortnight at grass helps transition animals to a grazing diet and cuts tetany risks.

If you are feeding meals at grass, use lightweight calf troughs that can be easily moved to prevent poaching and phase out concentrates as grass growth picks up.

10 What if weather takes a downturn?

If weather conditions take a turn for the worse, there is no shame in re-housing stock. By filtering cattle out to grass in smaller groups, there won’t be that many animals to bring back in.

Ultimately, do what is right for your farm. Don’t worry about the opinions of others should cattle need to come back inside.

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