Is a grassland reseed needed?

A grassland reseed could improve paddock and animal performance. Use our flow chart to help you decide whether a grassland reseed is needed. 

When is a reseed needed?

Reseeding should be considered if two or more of the following criteria have been met:

  • Sward productivity has fallen significantly
  • Proportion of sown species has fallen below 60%
  • High levels of native grasses and weeds are present
  • Significant evidence of soil compaction, especially at depth

Paddock performance

Some farmers may opt to reseed a set proportion of the farm each year, e.g. 10 or 15%, in a rotational pattern to ensure grass swards are regularly renewed.

There can be large variation in the performance of paddocks across the farm, so the best way to identify swards eligible for reseeding is to measure grass growth regularly to identify the poorest-performing fields. Using regular grass growth data can highlight fields that need attention and may require a full reseed.

Using a plate meter, nine Irish dairy farms measured grass throughout the grazing season in 2014. The results show wide variation in the performance of individual paddocks, varying by 280%.

Variation in paddock performance on nine Irish dairy farms

Farm number

Mean growth (t DM/ha)

Highest paddock (t DM/ha)

Lowest paddock (t DM/ha)

1

11.7

14.1

8.7

2

14.3

16.8

11.0

3

12.3

20.3

7.2

4

14.4

17.8

8.8

5

12.4

15.8

9.0

6

11.0

14.3

8.9

7

9.9

14.8

7.5

8

10.8

12.2

6.0

9

10.1

14.2

5.4

Influence on livestock performance

The progress of a grass reseed

PRG content (%)

Production (t DM/ha)

Herbage ME (MJ/kg DM)

Lost ME grown (MJ/ha)

Milk equivalent of lost ME (litres/ha)

Meat equivalent of lost ME* (kg LW/ha)

Concentrate cost to replace lost ME^ (£/ha)

95

13.5

12.0

 

 

 

 

90

12.6

11.8

13,320

1,885

133

197

80

11.2

11.5

33,200

4,698

332

491

70

9.8

11.3

51,260

7,254

513

759

60

8.4

11.0

69,600

9,849

696

1,030

50

7.0

10.8

86,400

12,226

864

1,279

ME = Metabolisable energy

PRG = Perennial ryegrass

DM = Dry matter

*assuming 100 MJ per 1 kg of gain for 350 kg growing cattle

^based on 1.4p per MJ of ME

Pasture improvement flow chart

Click here to see the pasture improvement flow chart.

Useful links

The latest grass growth and quality figures, along with the latest updates and resources.

Read the Recommended Grass and Clover Lists

Find out more about reseeding after a dry summer

How to graze new leys on the platform

Learn more about choosing seed mixes for grazing platforms


Reseeding webinars

×