AFBI advise grazing or cutting heavy grass covers.
Northern Ireland’s research unit at Hillsborough has come out saying Northern Irish farmers need to get heavy covers grazed off or cut off.
Filling them up with nitrogen and leaving them grow on for a large first cut silage is not the right option as it could lead to poorer first cut silage quality and more cost next winter.
Research carried out last year by David Patterson would suggest that where a silage sward in early spring appears to be dominated by poorer grass species and has a relatively high proportion of dead material, this grass cover can be removed by either cutting and baling or grazing, which itself has a value.
Whilst this practice is likely to result in a lower yield, it will produce higher quality (higher energy) herbage at first cut.
In summary, for managing silage swards that have heavy, over-wintered covers the Hillsborough advice is:
1 Dead matter
These swards should be assessed for the level of dead material present.
If this is excessive a decision to graze or cut these swards in early spring will reduce the amount of dead material present in the sward at first cut and improve herbage quality.
2 Grow
If the swards have heavy covers but are green with acceptable levels of dead material present as was the case in mid-January this year, leaving them to grow on is likely to provide the same yield advantage as in 2017, but with an expected lower drop in quality.
3 Herd
If there is concern about being able to ensile enough grass for the herd requirements for next winter then leaving swards with high levels of dead material to grow on will still maximise the silage yields over two cuts. However, the grass quality penalty at the first cut will be costly to correct with extra concentrate feed use next winter.
Northern farmers should graze off heavy grass covers rather than leaving them build up for first-cut silage.
Using this knowledge, farmers should weigh up their options if they want to recover swards that are in poor condition in early spring. This will be influenced by their expectations for yield and quality especially for first cut silage, and the need to make best use of available farm resources in a cost-effective and sustainable manner.
As such, in March 2018 three grassland management options were compared:
‘Early graze’ areas were rotationally grazed using one day paddocks with weanlings from late March to early May‘Early cut’ areas were harvested and big baled each week during the same 5 week period, i.e. 1/5 of the area was cut and baled each week.‘Leave to grow’ areas were allowed to continue growing until ready for first cut silage.The trial ran from late March to mid July 2018 and all three areas were assessed for yield and quality at first and second cut silage.
Results
With regard to quantity, there were similar first cut yields when ‘early grazing’ and ‘early cutting’ were used but the sward which was left to grow had the highest yield (2,162 kg DM/ha more). However, there was no difference in second cut yield and when the grazed yield and big bale yield in the early season were added in, the total sward production up to mid-July was similar for all three systems.
With regard to quality, the management practice did not affect herbage dry matter or sugar content for either first-cut or second-cut silage.
However the energy value (ME) of the first cut silage was 7% lower when the over-wintered herbage was not removed but allowed to grow through to first cut silage.
Fertiliser application workshop
Teagasc in association with the Fertiliser Association of Ireland will again host the Precise Application of Fertilisers Workshop on Wednesday 27 February in Teagasc Moorepark. These workshops will be of particular interest to field advisors and agri-contractors. There will be presentations on fertiliser planning for contractors and fertiliser spreader technology. Four workshops will be run to demonstrate the correct set up of fertiliser spreaders to deliver the correct rate accurately. This is a free event.
Pre-registration is essential. To book online, follow this link: https://www.eventbrite.ie/e/precise-application-of-fertilisers-teagasc-moorepark-tickets-55563424699
There are 25 IASIS points available for attending this workshop.
AFBI advise grazing or cutting heavy grass covers.
Northern Ireland’s research unit at Hillsborough has come out saying Northern Irish farmers need to get heavy covers grazed off or cut off.
Filling them up with nitrogen and leaving them grow on for a large first cut silage is not the right option as it could lead to poorer first cut silage quality and more cost next winter.
Research carried out last year by David Patterson would suggest that where a silage sward in early spring appears to be dominated by poorer grass species and has a relatively high proportion of dead material, this grass cover can be removed by either cutting and baling or grazing, which itself has a value.
Whilst this practice is likely to result in a lower yield, it will produce higher quality (higher energy) herbage at first cut.
In summary, for managing silage swards that have heavy, over-wintered covers the Hillsborough advice is:
1 Dead matter
These swards should be assessed for the level of dead material present.
If this is excessive a decision to graze or cut these swards in early spring will reduce the amount of dead material present in the sward at first cut and improve herbage quality.
2 Grow
If the swards have heavy covers but are green with acceptable levels of dead material present as was the case in mid-January this year, leaving them to grow on is likely to provide the same yield advantage as in 2017, but with an expected lower drop in quality.
3 Herd
If there is concern about being able to ensile enough grass for the herd requirements for next winter then leaving swards with high levels of dead material to grow on will still maximise the silage yields over two cuts. However, the grass quality penalty at the first cut will be costly to correct with extra concentrate feed use next winter.
Northern farmers should graze off heavy grass covers rather than leaving them build up for first-cut silage.
Using this knowledge, farmers should weigh up their options if they want to recover swards that are in poor condition in early spring. This will be influenced by their expectations for yield and quality especially for first cut silage, and the need to make best use of available farm resources in a cost-effective and sustainable manner.
As such, in March 2018 three grassland management options were compared:
‘Early graze’ areas were rotationally grazed using one day paddocks with weanlings from late March to early May‘Early cut’ areas were harvested and big baled each week during the same 5 week period, i.e. 1/5 of the area was cut and baled each week.‘Leave to grow’ areas were allowed to continue growing until ready for first cut silage.The trial ran from late March to mid July 2018 and all three areas were assessed for yield and quality at first and second cut silage.
Results
With regard to quantity, there were similar first cut yields when ‘early grazing’ and ‘early cutting’ were used but the sward which was left to grow had the highest yield (2,162 kg DM/ha more). However, there was no difference in second cut yield and when the grazed yield and big bale yield in the early season were added in, the total sward production up to mid-July was similar for all three systems.
With regard to quality, the management practice did not affect herbage dry matter or sugar content for either first-cut or second-cut silage.
However the energy value (ME) of the first cut silage was 7% lower when the over-wintered herbage was not removed but allowed to grow through to first cut silage.
Fertiliser application workshop
Teagasc in association with the Fertiliser Association of Ireland will again host the Precise Application of Fertilisers Workshop on Wednesday 27 February in Teagasc Moorepark. These workshops will be of particular interest to field advisors and agri-contractors. There will be presentations on fertiliser planning for contractors and fertiliser spreader technology. Four workshops will be run to demonstrate the correct set up of fertiliser spreaders to deliver the correct rate accurately. This is a free event.
Pre-registration is essential. To book online, follow this link: https://www.eventbrite.ie/e/precise-application-of-fertilisers-teagasc-moorepark-tickets-55563424699
There are 25 IASIS points available for attending this workshop.
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