Throughout the BETTER Farm programme, the importance of increasing output has been well documented on these pages. More important is increasing output from grass.
While the farms are continually addressing soil fertility, being able to grow more grass from the same land area to graze and produce silage for additional cattle is a challenge.
Old swards with low levels of ryegrass will not be capable of sustaining a higher stocking rate. Older swards tend to have more natural grasses present and they are just not capable of using nitrogen to the same extent as perennial ryegrass.
However, an older sward that has been well managed can still possess a lot of ryegrass. Regularly liming ground, applying P and K and grazing tight or topping when needed to prevent the build-up of dead grass will encourage further tillering of ryegrass and reduce the amount of natural grass present. These swards will be better equipped to support a higher stocking rate.
Where ryegrass content is low, then the field needs to be reseeded. The farms involved in the BETTER Farm programme have all undertaken a reseeding programme.
Approximately 10% of swards have been targeted annually to be reseeded, although this can vary depending on the weather, finances and the demand for grass.
With grass growth now running well ahead of livestock demand, there will be a situation arising where a grass surplus will be building.
For some of the farms, this provides an opportunity to take out extra silage. For others, it offers an ideal opportunity to close off some older, unproductive swards for reseeding.
When selecting fields for reseeding, there are a number of considerations to be made first:
Soil analysis – does the sward need lime, P and K?Expense – reseeding can be expensive, so cashflow can be affected.Grass varieties – is it a cutting or grazing only sward or combination of both?Method – min-tilling is quick, whereas ploughing improves drainage and levels ground but may make ground too soft for grazing.Which field to reseed – do certain fields need draining or is it a dry field needed for grazing during a wet spell? When to reseed – spring, summer or autumn?When to reseed
When do you need to reseed a field is a question commonly asked of the BETTER Farm participants and advisers at open days.
Every field can produce an ideal sward cover if left ungrazed for a period of time and well fertilized.
The answer depends on how soon the field can be grazed again after stock have been moved off it.
Assuming that the sward is grazed tight to 4cm (300kg DM/ha) and dressed with 13 to 27 units of nitrogen throughout the year, it should be ready for grazing again in 14 to 21 days from late spring to late summer in reasonable growing conditions.
If the sward is struggling to grow a cover of grass with an average height of 10cm to 12cm (1,600kg to 2,000kg DM/ha) with a dressing of up to one bag per acre of CAN, then it should be marked for reseeding.
By walking the grazing ground on a weekly basis, the programme farmers can quickly identify the poor performing swards on their farm.
Most of the farmers are trying to work off a three-day grazing paddock system and keep to a grazing rotation of 21 days.
The reason for sticking to the three-day paddocks is that grass will start to reshoot after three days.
Therefore, holding cattle on a paddock for longer than this length of time means there is a danger of cattle eating off the regrowth and reducing grass yield.
The paddocks will consistently struggle to produce enough grass to carry livestock. This is an indication of poor management rather than poor grassland performance.
Reseeding in spring will require a post-emergence spray for weeds. In summer and autumn, there will still be weeds established in a reseed but they are often less vigorous at these stages of the year.
Soil fertility
Ideally, there should be a soil analysis taken before reseeding to determine lime, P and K status.
With permanent grass swards that have received regular applications of chemical fertilizer, there will be a tendency for the soil to be naturally acidic.
The more acidic the soil, the greater the likelihood of a poor reseed establishing.
Low pH (5.5 to 5.7) will hinder clover development and will lock up soil nutrients. Applying lime after ploughing is beneficial to encourage seed establishment.
If the sward is being burned off and grass seed is being directly drilled into the soil, lime is again beneficial as the decaying grass can become acidic.
When reseeding, most of the BETTER farms are applying 10:10:20 to encourage seed establishment. Depending on soil analysis, the rate of application will vary but, at index 2, most farmers will apply two bags per acre to the seed bed.
Phosphate will encourage root development, helping the seed to establish, while potash will help with nutrient uptake and mobilisation through the grass seedling.
Ploughing
Conventional reseeding offers more than just a sward of young grass. Ploughing will open up the ground to improve drainage and aeration.
Getting farmyard manure onto the ground will also increase soil organic matter and increase earthworms, which will further improve soil aeration and drainage. Ground will be levelled where it was poached before.
However, ploughing can leave a reseed more difficult to manage in terms of ground conditions. Ground can be soft if the seedbed was over worked.
If weather conditions turn unfavourable after reseeding, then the field may not be capable of carrying livestock for a lengthy period.
Conventional reseeding is more expensive than minimum tillage methods and there is the added risk of ploughing down good soil and turning up infertile soil where the field is going from permanent (long-term) grass back to permanent grass.
In a crop rotation with a short grass ley, this is less of an issue, as the soil is regularly ploughed.
Min-tilling
To avoid ploughing down fertile soil and in order to bring the field back into production quicker, a number of the BETTER Farm participants have opted to use minimum cultivation techniques.
The process involves burning off the existing sward with glyphosate and leaving for approximately 10 days.
Then the new grass seed is direct drilled into the existing seedbed. Grazing off the dead grass is a benefit, as is applying lime beforehand.
The success depends on the degree of soil contact. Some machines will stitch in grass seed and can have varying degrees of success.
The farmers who used the grass drill had greater success as the seed was firmly placed in the soil at the correct depth. Slug pellets were also used.
Min-tilling was cheaper to carry out than conventional reseeding by €70 to €80, depending on contractor charges. As the soil surface was not disturbed, the farmers who used min-tilling to reseed last year were able to start grazing sooner, with some grazing the swards with light stock six weeks after drilling grass seed.
Getting stock on to graze again is crucial to keep the old grass from regenerating. The programme farmers have been using weanlings or sheep to manage reseeded swards. Lighter stock have grazed for a short period to encourage plant tillering.
Whichever method is used, the programme farmers have benefitted enormously from reseeding grassland.
The greatest benefit has been realised early and late in the year when older swards see production fall off sharply.
It is these younger swards that have allowed the programme farmers to carry increased stocking levels and achieve higher weight gains from grass.
Spreading the costs outlined in Table 1 over 10 years makes reseeding cheap, relative to spreading more fertilizer and improved performance.
At €21 to €28/acre over 10 years, it costs approximately 10kg to 12kg of liveweight gain, which young grass will more than deliver.
Throughout the BETTER Farm programme, the importance of increasing output has been well documented on these pages. More important is increasing output from grass.
While the farms are continually addressing soil fertility, being able to grow more grass from the same land area to graze and produce silage for additional cattle is a challenge.
Old swards with low levels of ryegrass will not be capable of sustaining a higher stocking rate. Older swards tend to have more natural grasses present and they are just not capable of using nitrogen to the same extent as perennial ryegrass.
However, an older sward that has been well managed can still possess a lot of ryegrass. Regularly liming ground, applying P and K and grazing tight or topping when needed to prevent the build-up of dead grass will encourage further tillering of ryegrass and reduce the amount of natural grass present. These swards will be better equipped to support a higher stocking rate.
Where ryegrass content is low, then the field needs to be reseeded. The farms involved in the BETTER Farm programme have all undertaken a reseeding programme.
Approximately 10% of swards have been targeted annually to be reseeded, although this can vary depending on the weather, finances and the demand for grass.
With grass growth now running well ahead of livestock demand, there will be a situation arising where a grass surplus will be building.
For some of the farms, this provides an opportunity to take out extra silage. For others, it offers an ideal opportunity to close off some older, unproductive swards for reseeding.
When selecting fields for reseeding, there are a number of considerations to be made first:
Soil analysis – does the sward need lime, P and K?Expense – reseeding can be expensive, so cashflow can be affected.Grass varieties – is it a cutting or grazing only sward or combination of both?Method – min-tilling is quick, whereas ploughing improves drainage and levels ground but may make ground too soft for grazing.Which field to reseed – do certain fields need draining or is it a dry field needed for grazing during a wet spell? When to reseed – spring, summer or autumn?When to reseed
When do you need to reseed a field is a question commonly asked of the BETTER Farm participants and advisers at open days.
Every field can produce an ideal sward cover if left ungrazed for a period of time and well fertilized.
The answer depends on how soon the field can be grazed again after stock have been moved off it.
Assuming that the sward is grazed tight to 4cm (300kg DM/ha) and dressed with 13 to 27 units of nitrogen throughout the year, it should be ready for grazing again in 14 to 21 days from late spring to late summer in reasonable growing conditions.
If the sward is struggling to grow a cover of grass with an average height of 10cm to 12cm (1,600kg to 2,000kg DM/ha) with a dressing of up to one bag per acre of CAN, then it should be marked for reseeding.
By walking the grazing ground on a weekly basis, the programme farmers can quickly identify the poor performing swards on their farm.
Most of the farmers are trying to work off a three-day grazing paddock system and keep to a grazing rotation of 21 days.
The reason for sticking to the three-day paddocks is that grass will start to reshoot after three days.
Therefore, holding cattle on a paddock for longer than this length of time means there is a danger of cattle eating off the regrowth and reducing grass yield.
The paddocks will consistently struggle to produce enough grass to carry livestock. This is an indication of poor management rather than poor grassland performance.
Reseeding in spring will require a post-emergence spray for weeds. In summer and autumn, there will still be weeds established in a reseed but they are often less vigorous at these stages of the year.
Soil fertility
Ideally, there should be a soil analysis taken before reseeding to determine lime, P and K status.
With permanent grass swards that have received regular applications of chemical fertilizer, there will be a tendency for the soil to be naturally acidic.
The more acidic the soil, the greater the likelihood of a poor reseed establishing.
Low pH (5.5 to 5.7) will hinder clover development and will lock up soil nutrients. Applying lime after ploughing is beneficial to encourage seed establishment.
If the sward is being burned off and grass seed is being directly drilled into the soil, lime is again beneficial as the decaying grass can become acidic.
When reseeding, most of the BETTER farms are applying 10:10:20 to encourage seed establishment. Depending on soil analysis, the rate of application will vary but, at index 2, most farmers will apply two bags per acre to the seed bed.
Phosphate will encourage root development, helping the seed to establish, while potash will help with nutrient uptake and mobilisation through the grass seedling.
Ploughing
Conventional reseeding offers more than just a sward of young grass. Ploughing will open up the ground to improve drainage and aeration.
Getting farmyard manure onto the ground will also increase soil organic matter and increase earthworms, which will further improve soil aeration and drainage. Ground will be levelled where it was poached before.
However, ploughing can leave a reseed more difficult to manage in terms of ground conditions. Ground can be soft if the seedbed was over worked.
If weather conditions turn unfavourable after reseeding, then the field may not be capable of carrying livestock for a lengthy period.
Conventional reseeding is more expensive than minimum tillage methods and there is the added risk of ploughing down good soil and turning up infertile soil where the field is going from permanent (long-term) grass back to permanent grass.
In a crop rotation with a short grass ley, this is less of an issue, as the soil is regularly ploughed.
Min-tilling
To avoid ploughing down fertile soil and in order to bring the field back into production quicker, a number of the BETTER Farm participants have opted to use minimum cultivation techniques.
The process involves burning off the existing sward with glyphosate and leaving for approximately 10 days.
Then the new grass seed is direct drilled into the existing seedbed. Grazing off the dead grass is a benefit, as is applying lime beforehand.
The success depends on the degree of soil contact. Some machines will stitch in grass seed and can have varying degrees of success.
The farmers who used the grass drill had greater success as the seed was firmly placed in the soil at the correct depth. Slug pellets were also used.
Min-tilling was cheaper to carry out than conventional reseeding by €70 to €80, depending on contractor charges. As the soil surface was not disturbed, the farmers who used min-tilling to reseed last year were able to start grazing sooner, with some grazing the swards with light stock six weeks after drilling grass seed.
Getting stock on to graze again is crucial to keep the old grass from regenerating. The programme farmers have been using weanlings or sheep to manage reseeded swards. Lighter stock have grazed for a short period to encourage plant tillering.
Whichever method is used, the programme farmers have benefitted enormously from reseeding grassland.
The greatest benefit has been realised early and late in the year when older swards see production fall off sharply.
It is these younger swards that have allowed the programme farmers to carry increased stocking levels and achieve higher weight gains from grass.
Spreading the costs outlined in Table 1 over 10 years makes reseeding cheap, relative to spreading more fertilizer and improved performance.
At €21 to €28/acre over 10 years, it costs approximately 10kg to 12kg of liveweight gain, which young grass will more than deliver.
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