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News > Making Grass Work for the Dairy Herd in a Dry Spring


Making Grass Work for the Dairy Herd in a Dry Spring

April 29, 2020

Conail Keown – CAFRE Dairying Development Adviser

Grazing conditions on farm are excellent at the moment with only 4% of the average April rainfall so far this month and these dry conditions have allowed dairy farmers take full advantage of grass as the cheapest feed available. However there is a big variation across the country in grass quality and grazing management.

Those who got cows out early and have now established a wedge of grass on their grazing blocks are in a good position in terms of grazing and grass management. While on other farms where turnout was delayed and pre grazing covers were in excess of 3500kgDM/ha resulting in poor utilisation, drop off in milk quality and lower production from grazed grass.

The ground conditions in counties Fermanagh and Tyrone are perfect, while parts of counties Antrim, Down, Derry and Armagh are beginning to show signs of moisture deficit in soil with grazing regrowth slowing down.

Dr Kathryn Huson manages the GrassCheck project, run by AFBI and AgriSearch. Dr Huson makes the comment that current on-farm readings for soil moisture range from 3 centibars on one farm in Tyrone and up to 200 centibars on a County Down farm with shallow, free draining soils. The majority of farms in Antrim, Armagh and Down are showing higher readings, meaning grass growth rates are likely to be restricted by the soil moisture deficit. The higher the reading, the more likely that grass growth will be significantly reduced in the current conditions, impacting on yield potential.

When the rain comes then grazed grass will once again play a pivotal role in controlling feed costs on farms across Northern Ireland over the next three to four months. After all it is the competitive advantage for milk producers in Northern Ireland. While purchased feed is an important requirement on all dairy farms, the majority of milk is produced from grazed grass or conserved forage. It is vital therefore that we get the management of grass and grazing correct in order to maximise its potential.

Have you got the skills set to capitalise on this and what can be done immediately on your farm to improve grass growth and utilisation?

The Conway dairy herd in the second rotation of the 2020 grazing season.
Why you can’t manage what you don’t measure!

Maintaining a constant supply of high quality leafy grass is the challenge. The simple task of walking the grazing block weekly and measuring grass can help meet this challenge; eliminating the fluctuation in pre grazing yields and problems of not enough or too much grass on the farm. The list of benefits a dairy business can expect from starting to measure grass can be quite extensive. Below are a few benefits relevant in the current climate:

• Take the guess work out of grass management;
• Know when to start the second rotation;
• Identify surplus grass for cutting;
• Identify grass deficits when buffer feed or additional meal is required;
• React to rapidly changing grass supply on farm;
• Reduce cost in a volatile milk market;
• Maintain and improve grass quality.

The list can go ‘on and on’ but the reality is walking the grazing block regularly will allow you to make better informed and more effective grassland management and grazing decisions.

Farmer Focus – Peter and Niall Conway, Strangford Co Down

Grazing management was high up the agenda at a recent Ardglass BDG discussion group meeting held last week. When under the current Covid19 restrictions the discussion was held in a new virtual format or video conference style, which was a first for the Ardglass men. The focus was very much on grass and the grazing conditions each of the members were experiencing. Even within the group the variation in grass performance is remarkable, and proves the point that ‘no two farms are the same’ and require different degrees of management.

The Conway farm is situated on the East side of County Down just outside the village of Strangford. So far this month only 3% of the average April rainfall has landed on the Conway farm and the farm is starting to show signs of moisture deficit with grass growth slowing down.

The Conway’s manage 380 spring calving cows on the farm, calving started on the 1st Feb with cows progressing to grass as they calved from 6th February. 50% of the herd calved in the first 11 days. The herd is now nearing the end of the second rotation of the grazing area in what Niall describes as excellent conditions, – “Grass regrowth has been on target so far with cows currently going into pre-grazing covers of 3100kgDM/ha. Early nitrogen application has helped us get to this stage on the farm, however I do see growth rates slowing down over the past 10 days”.

Dr Debbie McConnell, AFBI also makes the point that moisture deficit similar to what the Conway’s are experiencing, results in reduced or very limited uptake of nutrients by the grass plant and subsequently less grass growth.
Nitrogen applied on the Conway farm started with the first application of 29kg/Ha urea on the 3rd February. The second application of 58Kg/Ha was on 1st March when moisture was not an issue, and a third application of 29Kg/Ha on 20th March along with some slurry applied in mid-February takes the nitrogen total to 125 Kg/Ha across the grazing block. Niall will be going again this week with nitrogen and some compound fertiliser targeted at paddocks deficient in P and K nutrients.

The grass demand on the farm is currently at peak and breeding will start this week, we have started measuring grass twice per week in an attempt to manage the drop off in grass supply. Normally grass supply would be ahead of demand on the farm with surplus made into silage, instead this year we may have to increase meal feeding or introduce a buffer feed of silage to reduce grass demand

Niall Conway
Conway Grass Performance 27th April 2020  
Grass growth (kgDM/ha/day) 45
Grass growth 20th April (kgDM/ha) 75
Average farm cover (kgDM/ha) 2358
Average cover per cow (kgDM) 292
Stocking rate (cows/ha) 2.93
Grass demand (kgDM/ha/day) 47
Conway Grass Performance 27th April 2020  
Milk yield (litres) 27
Butterfat % 4.33
Protein % 3.44
Total solids per cow (kgs/cow/day) 2.05
Meal feeding (kgs/cow/day) 2

• Grazed grass can play a major role in reducing feed costs on farm, to capitalise on this we need to improve grazing management.
• Soil moisture deficit is starting to limit grass growth on farms in Counties Down, Antrim and Armagh and appropriate action is needed to limit grass demand on these farms.
• Measure to manage – walking the grazing block regularly will allow you to make better informed, more effective grassland management and grazing decisions.