Now that the closed period is over… should I spread?

Our fertiliser world is a changing. We now need to focus more on nitrogen use efficiency, ammonia and nitrous oxide emissions. As part of their marginal abatement curve Teagasc have identified fertiliser type as a key weapon in our fight to lower ammonia and nitrous oxide emissions from agriculture.

Switching from CAN to urea-based fertilisers lowers nitrous oxide losses but increases the risk of ammonia losses. Protecting our urea fertilisers with a technology to lower ammonia loses allow us to limit both.

To maximise our nitrogen use efficiency, we also need to become more aware of soil temperature, grass cover and weather forecasts before we hook up the spreader. We also need to maximise our use of home-produced organic fertilisers in our early spring fertiliser plans.

The timing and rate of fertiliser N application are key decisions for every livestock farmer.

Research has shown a large range in grass response to early N (between 5 to 18 kg DM/kg N applied). While the appropriate application of early N is beneficial, the incorrect application of early N is wasteful, costly, pollutes water and increases greenhouse gas emissions – Teagasc.

The following “Do’s & Don’ts” produced by Teagasc should guide your decisions around early N application.

Do:

1. Check weather forecast (www.met.ie) prior to making fertiliser N applications

• • Check the soil moisture deficits (SMD) for your area and only spread if SMD is greater than zero; and
  •  Only apply fertiliser N when soil temperature is greater than 5°C and rising.

2. Target fields for early N that are most likely to respond to an early N application:

• • Perennial ryegrass / recently reseeded fields
  • Drier, free draining fields
  • Fields with a grass cover of greater than 400 kg DM/ha or 5 cm grass
  • Fields with optimum soil fertility, i.e. good P and K status, pH > 6.2

3. Replace chemical N fertiliser on approx. 1/3 of the farm with cattle slurry. Target slurry applications to fields with low P & K levels & low grass covers; 25 m³/ha (2,500 gals/ac) by low emission application will supply ~25 kg/ha (20 units/ac) of available N.
4. Use protected urea (NBPT) for early N applications
5. Apply up to 30 kg N/ha (24 units N/ac) in 1st split in late January or early February and avoid fields that have received an application of cattle slurry.
6. Link your early N application strategy with spring feed budget for the farm.
7. Calibrate and maintain your fertiliser spreader in good condition.

Don’t:

1. Never apply fertiliser on waterlogged or frozen soils.
2. Don’t apply fertiliser if a yellow rainfall warning is in place or is forecast within the next 48 hours.
3. Never apply fertiliser into buffer margins & know your buffer margins.
4. Delay N on bare fields (<400 kg DM/ha); instead spread on fields with 5 cm (cover of 400 kg DM/ha) grass cover or greater.
5. Don’t apply fertiliser N on fields that receive slurry in the first round.
6. Don’t apply more than 30 kg N/ha (24 units N/ac) in 1st split in late January/early February.
7. Don’t apply more than 90 kg N/ha (Slurry N + Chemical N) in total up to early April

Nutrient Content of slurry (1000 gals/acre)

Spring fertiliser recommendations

N = 70 units to April 1^st, 90 units to May 1^st

P = 20 units ( + 8 units per index drop)

K = 40 units ( + 25 units per index drop)

Spring fertiliser Plan:

Slurry:

Chemical Fertiliser

Protected Urea from Dairygold

For several years, Dairygold has been leading the industry in offering fertilisers which are based on protected urea and you our customers have been leading the industry in your use of such products. These products increase annual grass growth while decreasing ammonia and greenhouse gas (GHG) emissions. In 2020 we will have an increased range of proven technologies that protect our urea fertilisers.

In 2020, we will be continuing this trend. We will have 3 differing protected ureas on offer for the coming season:

1. Agrotain which contains NBPT
2. Limus which contains 75% NBPT + 25% NPPT
3. Alzon which contains 2-NPT + MPA

Please contact our Inside Sales Team on 022 31644, your local Area Sales Manager or your Branch Agri Lead for more information on these products.