Winter Pastures

Maximising winter pasture with EASY Liquids fertilisers

Increasing the production of home grown feed with nitrogen fertiliser is still one of the best ways to help meet the feed requirements of milking herds and lift milk production.

The argument for applying winter nitrogen to boost feed growth is all the more compelling for dairy farmers carrying high stocking rates and for those who have already had poor seasonal conditions reduce pasture growth.

Topdressing with a nitrogen fertiliser can assist farmers to capitalise on the natural increase in pasture growth as we move into spring. Regular urea applications are commonplace on many dairy farms, particularly on good grassy pastures, where around 10 kg of dry matter (DM) can be expected to grow per kilogram of nitrogen applied in autumn1.

Along with urea, dairy farmers can choose between a number of different nitrogen fertiliser sources and blends to suit their agronomic and operational needs.

Products containing nitrate nitrogen should be considered during the winter months. Typically, cold soils and overcast conditions slow the conversion of urea and ammonium nitrogen products to nitrate in the soil.

One option for many dairy farmers, particularly where pastures are irrigated, is Incitec Pivot Fertilisers’ liquid nitrogen fertiliser, EASY N.

EASY N is a liquid nitrogen source that contains around a quarter of its nitrogen in the nitrate form, which is immediately available for pastures to respond to.

EASY N can easily be applied using a boom spray, or directly injected into irrigation lines with centre pivot systems, lateral irrigators or where other sprinkler systems are used.

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Managing nitrogen and grazing

With autumn pasture sowing all but complete, attention to maximising the
quality and quantity of dry matter production needs to be considered.
There are two key areas in pasture which need close management – nitrogen and grazing.

Nitrogen is used to maximise the dry matter (DM) production from pastures. Here are some tips for nitrogen use:

  • Apply to paddocks that have a good base fertility of phosphorous and potassium.
  • Apply when there are adequate soil moisture levels for growth.
  • Apply to paddocks that have a good pasture base, such as grass dominant with few weeds.
  • Apply to avoid a predicted feed gap to produce a feed wedge for livestock or fodder conservation.
  • Only apply nitrogen if additional feed produced can be utilised.
  • Nitrogen recovery is greatest when applied within four days of grazing when there is a reduced rick of leaf burn.
  • Allow at least 2-3 weeks active pasture growth prior to grazing.
  • Highest efficiency use of nitrogen is in single applications of 25-50 kg N/ha1.
  • Apply nitrogen prior to a significant rain event of more than 10mm or with irrigation.
  • Use a nitrogen fertiliser with a nitrate component when soil temperatures are less than 12°C.

When pastures growth rates are low (less than 10 kg DM/ha/day) applications of nitrogen can almost double production. Where growth rates of pasture are moderate

to high (between 60-100 kg DM/ha/day), nitrogen applications can increase production by 15-20%2.

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Grazing management

Grazing management is critical for successfully establishing and maintaining pasture.

Rotations should be set around when the plants can be grazed. For a ryegrass clover sward, this is at the 2½ to 3 leaf stage of the ryegrass.

Grazings should leave some residual leaf, but not an excess amount. This allows the plant to capture sunlight with the residual leaf, which reduces soluble carbohydrate reserves and stress.

Under-grazing will lead to poor utilisation, aerial tillering and subsequent density decline.

Newly established pastures should have a light grazing as soon as the seedling will withstand ‘pulling’ (i.e if the plants don’t come out by the root, the pasture is ready

for a short, light grazing). A nitrogen application should then be applied at 25-50 kg N/ha. Each subsequent grazing should also have nitrogen applied after, if the

additional dry matter produced can be consumed or conserved.

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EASY N in pasture

With days getting shorter and cooler, consider using a nitrate form of nitrogen from mid-May until soil temperatures increase in late September, as plants will be able to access it immediately and it can be utilised even under cold temperatures.

EASY N is a real consideration for dairy farmers as a nitrogen application. Not only does it contain ammonium nitrate, but it also provides the flexibility of a one pass application containing insecticides and pasture growth regulators, such as gibberellic acid.

EASY N analysis
Nitrogen form

Analysis % (w/v)

Nitrate

10.5

Ammonium

10.5

Urea

21.5

Total N

42.5

 

The nitrate nitrogen in EASY N is immediately available for pasture uptake even under cool soil temperatures. Urea can take up to four weeks for half of

it to become plant available at soil temperatures of 10°C.

Nitrification under cool temperatures table
Soil temperature (°C)

50% of ammonium converted after

5

6 weeks

8

4 weeks

10

2 weeks

20

1 week

 

Source: Amberger & Vilsmeir, 1984

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EASY application

Applying EASY N through irrigation is an efficient method of supplying nitrogen to  pastures in terms of getting the nutrient into the plant.

Regular scheduled irrigation will enhance the density and growth of plant roots.

EASY N can be applied through fixed line sprinklers, centre pivots, boomsprays, flood irrigation, as well as foliar sprays.

Using EASY N in fertigation applications can also save farmers time by simplifying the application operation, allowing greater control over the rates applied and frequency of fertiliser applications compared with arranging contract spreading of urea.

EASY N can also be used as a carrier for applying gibberellic acid to pastures.

Gibberellic acid is a plant growth regulator that stimulates growth through cell expansion, resulting in stem and leaf elongation.

By applying EASY N and gibberellic acid together, farmers can benefit from two forms of growth assistance. A one pass application of EASY N and gibberellic acid within four days of grazing provides a low volatile nitrogen source with the potential for rapid dry matter response under cool conditions.

For more information on EASY N’s compatibility with plant growth regulators, speak to your local Incitec Pivot Fertilisers’ Distributor.

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Nitrogen based fertilisers for your pasture

Pasture product

Product rate to achieve 40 kg N/ha

Kg/ha

kg N/ha as nitrate nitrogen

When to use product

N

P

K

S

EASY Liquids

EASY N

94 L/ha

40

0.0

0.0

0.0

9.9

Can be used all year round, particularly in cooler months as an ammonium nitrate source. Apply with boom spray or fertigation.

BOOSTA™ fertiliser range

PastureBOOSTA®

168

40

6.2

21.8

6.9

0.0

Use in warmer months* where nitrogen, phosphorus, potassium and sulphur are required.

GrassBOOSTA™

134

40

0.0

0.0

20.1

0.0

Use in warmer months* where nitrogen is required in conjunction with sulphur.

HayBOOSTA®

342

40

16.1

81.7

15.7

0.0

Use in warmer months* where nitrogen, phosphorus, potassium and sulphur are required, following hay or silage cut on low potassium soils.

FodderBOOSTA®

348

40

26.4

67.8

21.2

0.0

Use in warmer months*. FodderBOOSTA is a NPKS fertiliser for pasture and other fodder crops and is ideal where soil phosphorus and potassium levels need a boost.

Greentop™ fertiliser range

Greentop

223

40

11.2

0.0

42

0.0

Use in warmer months* for topdressing improved grass pastures. Greentop can also help with pasture regrowth response.

Greentop Complete

208

40

16.7

20.8

13.8

0.0

Use in warmer months* for topdressing improved grass pastures. Greentop Complete can also help with pasture regrowth response.

Greentop K

122

40

0.0

13.4

3.5

0.0

Use in warmer months* for topdressing improved grass pastures. Greentop K can also help with pasture response.

Greentop K+

150

40

0.0

31.5

0.0

 

Use in warmer months* for topdressing improved grass pastures. Greentop K+ can also help with pasture response.

Urea and blends

Granular urea

87

40

0.0

0.0

0.0

0.0

Lowest cost from of nitrogen. Apply in the warmer months*, where only nitrogen is required.

ENTEC® Urea

87

40

0.0

0.0

0.0

0.0

ENTEC is an Ammonium stabiliser which can help improve nitrogen uptake and efficiency.

Green Urea™7

87

40

0.0

0.0

0.0

0.0

Apply in the warmer months*. Helps protect urea from volatilisation loss.

Green Urea™14

87

40

0.0

0.0

0.0

0.0

Apply in the warmer months*. Helps protect urea from volatilisation loss.

Gran-Am®

198

40

0.0

0.0

47.5

0.0

Can be used all year round to supply nitrogen and sulphur to pasture.

DAP

222

40

44.4

0.0

0.0

0.0

Use in warmer months* where nitrogen and phosphorus are required.

*Warmer months – late spring, summer and early autumn, where soil temperatures are typically more than 15°C.

 

For further information, contact your local Incitec Pivot Fertilisers’ Distributor or freecall 1800 009 832.

www.incitecpivot.com.au

This is a guide only, which we hope you find helpful as a general tool. While Incitec Pivot Fertilisers has taken all reasonable care in the preparation of this guide, it should not be relied on as a substitute for tailored professional advice and Incitec Pivot Fertilisers accepts no liability in connection with this guide. Talk to your local Incitec Pivot Fertilisers Distributor Agronomist about soil testing and arranging a specific fertiliser recommendation that best suits your needs.

 

Source:

1. McKenzie FR, Jacobs JL and Kearney G 2003 “Long-term effects of multiple applications of nitrogen fertiliser on grazed dryland perennial ryegrass/white clover dairy pastures in south-west Victoria” Australian Journal of Agricultural Research vol. 54, pp 471-476.

2. Kemp, H “Getting value from your fertiliser” workshops held in autumn 1994 by NSW Department of Primary Industries in the Southern Highlands and South Coast of NSW.

® EASY N, Gran-Am, CAL-GRAN, FASTGRASS, PastureBOOSTA, HayBOOSTA, FodderBOOSTA and EASY Liquids are registered trademarks of Incitec Pivot Limited. ™ Green Urea, Greentop, GrassBOOSTA and EASY NP are trademarks of Incitec Pivot Limited.

® ENTEC is a registered trademark of K&S Nitrogen GmbH.

 

Incitec Pivot Fertilisers is a business of Incitec Pivot Limited, ABN 42 004 080 264

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