Grass growth rates have rocketed this week as all the ingredients for growth are present – warmth, moisture, long daylight hours and a big release of background nitrogen from warmer soils.

The official average grass growth figure of 70kg/day is certainly underestimating actual growth rates at present, because these are an amalgam of all farms recording on PastureBase, some of whom may not have recorded in two weeks.

The point here is that most farms are growing 80-90kg of grass per hectare per day on average. This average figure can be deceptive because covers that are nearly fit for grazing are probably growing 1.5 times the average, so it’s not surprising that these could be growing 130kg to 140kg/day now.

So a field at the ideal pre-grazing yield of 1,400kg today, could be gone too strong at 1,700kg in just a few days’ time.

The big risk at the moment is that the whole farm gets out of hand because correct action isn’t taken in time. Instead of grazing covers of 1,400kg, cows and cattle go in to covers of 1,700kg and get an extra day in it.

That means the paddock they should be going into next has grown an extra 300kg and is now at 2,000kg and cows get an extra two days in it. Meanwhile, covers that are a week away from grazing are already at 1,400kg.

This is a difficult problem to solve and the only way to avoid it is by skipping over paddocks for silage as they get too strong for grazing.

Closing up these paddocks will tighten up the area for grazing and increase the daily demand for grass. Right now a very high demand is OK, but this must be only temporary as growth rates won’t remain high for much longer.

With a mixed forecast for next week, I’m of the view that some, not necessarily all, of these surplus paddocks should be cut out this weekend to bring the stocking rate and demand back to a more sustainable level. A sustainable demand is somewhere in the mid 60s, which is a stocking rate of around 3.8-4 livestock units/ha.

Sward Watch

  • Phenomenal growth rates at present. PastureBase average is over 70kg/ha/day.
  • Big risk that pre-grazing yields will get too strong so be proactive by skipping over high covers and select them for silage.
  • Aim for your average farm cover to be between 160kg and 180kg per livestock unit, or roughly enough grass for 10 days ahead.
  • Higher-stocked farms need to continue spreading nitrogen on grass-only swards, at a rate of around 0.8 units of N/day or 15-17 units/acre after each grazing.
  • Lower-stocked farms or highclover paddocks can get away with much less nitrogen.
  • Kevin Moloney – Knockanore, Co Waterford

    I’ve skipped over three paddocks, with another one or two possibly to come out. We’ve just began the third round of grazing, with cows being followed by a bag and a half of 18-6-12 with sulphur in the second round.

    For the third round, we’ll be following cows with 38% KAN with sulphur at a rate of about 15 units N/acre.

    We’ve two paddocks tilled and ready to sow multispecies in as soon as the weather improves. We’ve two weeks of AI complete, with two-thirds of the cows served.

    Our farm manager Brendan is leaving us shortly so we’re currently on the hunt for an enthusiastic young person to replace him.

    Stocking rate (cows/ha) 4.6

    Growth rate (kg/day) 75

    Average farm cover (kg/cow) 148

    Yield (l/cow) 24

    Fat % 4.42

    Protein% 3.72

    Milk solids (kg/cow) 2.01

    Supplement fed (kg/cow/day) 1.5

    Ivan Ferguson – Fahan, Co Donegal

    We’ve a total of seven paddocks earmarked for mowing from the milking platform, with our main issue now being the weather. Ground has quickly gotten wet, with cows poaching a bit on Tuesday morning.

    Growth is excellent, with heavier covers growing in excess of 100kg/DM/ha per day. The difficulty now will be controlling grass. We’re following cows with slurry using a trailing show at a rate of 2,500gallon/acre which is working really well for us.

    Breeding is due to kick off in the coming week, with all cows tail-painted pre-breeding. Any cows that still have tail paint after three weeks are scanned.

    Stocking rate (cows/ha) 3.82

    Growth rate (kg/day) 89

    Average farm cover (kg/cow) 167

    Yield (l/cow) 28

    Fat % 4.17

    Protein% 3.7

    Milk solids (kg/cow) 2.24

    Supplement fed (kg/cow/day) 3

    Brendan Horan – Teagasc Curtins, Co Cork

    Growth has been really good for the last week at 75kgDM/ha even after excluding paddocks which are too strong for grazing. We have been removing surpluses each week and keeping demand at 65-70kg/ha/day.

    We began the third round at the weekend and we’re going in to covers of 1,300kg DM/ha, with our rotation length pulled back to 17 days. Cows are being followed with 30 units of protected urea.

    This is part of our perennial ryegrass 250kg N trial. To date, 100kg of N has been applied to the swards, along with 12kg of slurry. Soil fertility is excellent so we are staying with protected urea with no P or K spread artificially.

    Stocking rate (cows/ha) 3.7

    Growth rate (kg/day) 74

    Average farm cover (kg/cow) 172

    Yield (l/cow) 21.3

    Fat % 4.71

    Protein% 3.42

    Milk solids (kg/cow) 1.8

    Supplement fed (kg/cow/day) 0