We are at challenge nine of our 10 BETTER farm beef programme challenges. The tenth and final challenge will be the financial challenge, which will detail the eagerly anticipated e-Profit Monitor results from phase three of the programme.
The finishing touches are being put on these reports and they will be profiled in the Irish Farmers Journal in the coming weeks.
In the meantime, we will focus on challenge number nine – the soil health challenge. The objective was to improve soil fertility on the programme farms through frequent soil sampling and targeted applications of lime and organic and chemical fertilisers based on nutrient plans. This wasn’t a mandatory challenge, but 21 out of the 23 programme farmers signed up to the task. The 21 farmers encompassed a range of soil type and nutrient statues.
Targets
When we talk about growing more grass, the first thing that comes to most people’s minds is either infrastructure –putting up paddocks, roadways or water troughs – or reseeding. While there is no doubt that these things can lead to improved grass production, the factor underpinning this is soil fertility. Trying to grow more grass on land with poor soil fertility is like trying to drive a car with the handbrake on – a futile exercise.
The three key ingredients of soil fertility are pH (lime), phosphorous (P) and potassium (K). What about nitrogen (N)? Well let’s use another mechanical metaphor: N is the fuel that powers grass growth during the growing season but P, K and lime are the engine that drives the growth. No matter how much fuel you use, it won’t work without an engine.
Trying to grow more grass on land with poor soil fertility is like trying to drive a car with the handbrake on – a futile exercise
When looking at the targets and ultimately correcting soil fertility, lime is the first port of call.
Research shows that correcting pH alone on soils with poor levels of P and K will still increase grass growth by 10%. Properly limed soils also have a better structure and are quicker to break down organic matter.
On normal mineral soils, we target a minimum pH of 6.3. Below this, the soil will be more acidic. On peat-type soils, the target is a minimum of 5.5.
P and K are measured in mg/l and graded on a one-to-four index scale, based on the probability of a response to fertiliser application. Index one means a definite response and index four means no response. Needless to say, the target for our fields is to be at index three or four, which corresponds to at least 5.1mg/l of P or 101mg/l of K.
Maintenance
Significantly, once a soil reaches index four, only maintenance spreading is needed in order to account for the offtake via animals or conserved forage. To build up P and K, organic sources (slurries and FYM) and chemical fertilisers (18:6:12, 10:10:20 etc.) are the most common options.
While this sounds relatively straightforward, alarmingly only 10% of soils in Ireland are optimum for all three soil nutrients. The only way for you to know your soils’ situation is to soil-sample. Pending those results, a nutrient plan can be drawn up for your farm – including lime, fertiliser, slurry and FYM – to correct any nutrient deficiencies (see top tips for soil-sampling) and kick-start your effort to grow more grass this year.
Results
All farms were soil-sampled at the commencement of the programme in early 2017. Samples were taken each year, typically during the winter, to monitor progress. In this article, we will use 2019 samples to determine overall progress and the final results of the soil health challenge.
Overall, the results make for positive reading. Albeit from a good base, the average pH has moved closer towards the 6.3 target and now sits at 6.2. At the start of the programme, 11 farmers were already at optimum pH. Over the last three years, six other farmers have moved pH in the right direction and three of these have managed to hit the 6.3 target also.
Glen McDermott (pictured) is a good example of a positive pH move. In 2017, average pH was at 5.3. It is now sitting at 6.2. The significant change came as a result of spreading 86t of lime in 2017 and further applications while he was reseeding ground.
Glen McDermott improved his soil pH by spreading 86t of lime in 2017.
Going with 2t/ac on most of the grazing blocks in year one of the programme was a significant investment, but it has reaped dividends in terms of soil fertility and grass growth.
On P and K levels, there were also marked improvements. The average for P and K at the beginning of the programme was index 2. These have both moved up to index 3.
In terms of P, eight farmers are at optimum for P (index 3 or 4) while no farm is at index 1. Nine farms made improvements. For K, 11 farms made improvements, meaning 16 farms are at optimum (index 3 or 4).
Top tips for soil-sampling
A standard soil sample will give a soil’s pH, P, K, and magnesium status.Soil samples should be taken at least every five years and, on intensively stocked farms, they should be taken every two to three years. It is a mandatory task for farms in derogation.Soil samples cost approximately €20-30 per sample. A soil corer costs approximately €80 to purchase.Soil tests should be taken as late as possible after the last application of lime, P or K to avoid skewing the test results. Therefore, November to February are the best months in which to test. Make sure to take samples before spreading slurry this spring.Do not sample for two years after a lime application and three months after P or K application. Nitrogen spreading does not affect soil sample results.Each soil test should represent between 2-4ha of grassland.Use a soil corer – P will build up in the top 2-3cm of the soil so it is important to take a core over 5cm in depth.Take samples in a fashion that give a fair reflection of the designated area – best practice is to walk in a W-shaped pattern across the field.Avoid any unusual spots such as drinking troughs, dung patches, waterlogged areas, etc.Take 20 to 25 cores per sample.Remember to ID each sample box and correctly correspond each sample ID with the area sampled – it is best to write the ID on a map of the farm.
We are at challenge nine of our 10 BETTER farm beef programme challenges. The tenth and final challenge will be the financial challenge, which will detail the eagerly anticipated e-Profit Monitor results from phase three of the programme.
The finishing touches are being put on these reports and they will be profiled in the Irish Farmers Journal in the coming weeks.
In the meantime, we will focus on challenge number nine – the soil health challenge. The objective was to improve soil fertility on the programme farms through frequent soil sampling and targeted applications of lime and organic and chemical fertilisers based on nutrient plans. This wasn’t a mandatory challenge, but 21 out of the 23 programme farmers signed up to the task. The 21 farmers encompassed a range of soil type and nutrient statues.
Targets
When we talk about growing more grass, the first thing that comes to most people’s minds is either infrastructure –putting up paddocks, roadways or water troughs – or reseeding. While there is no doubt that these things can lead to improved grass production, the factor underpinning this is soil fertility. Trying to grow more grass on land with poor soil fertility is like trying to drive a car with the handbrake on – a futile exercise.
The three key ingredients of soil fertility are pH (lime), phosphorous (P) and potassium (K). What about nitrogen (N)? Well let’s use another mechanical metaphor: N is the fuel that powers grass growth during the growing season but P, K and lime are the engine that drives the growth. No matter how much fuel you use, it won’t work without an engine.
Trying to grow more grass on land with poor soil fertility is like trying to drive a car with the handbrake on – a futile exercise
When looking at the targets and ultimately correcting soil fertility, lime is the first port of call.
Research shows that correcting pH alone on soils with poor levels of P and K will still increase grass growth by 10%. Properly limed soils also have a better structure and are quicker to break down organic matter.
On normal mineral soils, we target a minimum pH of 6.3. Below this, the soil will be more acidic. On peat-type soils, the target is a minimum of 5.5.
P and K are measured in mg/l and graded on a one-to-four index scale, based on the probability of a response to fertiliser application. Index one means a definite response and index four means no response. Needless to say, the target for our fields is to be at index three or four, which corresponds to at least 5.1mg/l of P or 101mg/l of K.
Maintenance
Significantly, once a soil reaches index four, only maintenance spreading is needed in order to account for the offtake via animals or conserved forage. To build up P and K, organic sources (slurries and FYM) and chemical fertilisers (18:6:12, 10:10:20 etc.) are the most common options.
While this sounds relatively straightforward, alarmingly only 10% of soils in Ireland are optimum for all three soil nutrients. The only way for you to know your soils’ situation is to soil-sample. Pending those results, a nutrient plan can be drawn up for your farm – including lime, fertiliser, slurry and FYM – to correct any nutrient deficiencies (see top tips for soil-sampling) and kick-start your effort to grow more grass this year.
Results
All farms were soil-sampled at the commencement of the programme in early 2017. Samples were taken each year, typically during the winter, to monitor progress. In this article, we will use 2019 samples to determine overall progress and the final results of the soil health challenge.
Overall, the results make for positive reading. Albeit from a good base, the average pH has moved closer towards the 6.3 target and now sits at 6.2. At the start of the programme, 11 farmers were already at optimum pH. Over the last three years, six other farmers have moved pH in the right direction and three of these have managed to hit the 6.3 target also.
Glen McDermott (pictured) is a good example of a positive pH move. In 2017, average pH was at 5.3. It is now sitting at 6.2. The significant change came as a result of spreading 86t of lime in 2017 and further applications while he was reseeding ground.
Glen McDermott improved his soil pH by spreading 86t of lime in 2017.
Going with 2t/ac on most of the grazing blocks in year one of the programme was a significant investment, but it has reaped dividends in terms of soil fertility and grass growth.
On P and K levels, there were also marked improvements. The average for P and K at the beginning of the programme was index 2. These have both moved up to index 3.
In terms of P, eight farmers are at optimum for P (index 3 or 4) while no farm is at index 1. Nine farms made improvements. For K, 11 farms made improvements, meaning 16 farms are at optimum (index 3 or 4).
Top tips for soil-sampling
A standard soil sample will give a soil’s pH, P, K, and magnesium status.Soil samples should be taken at least every five years and, on intensively stocked farms, they should be taken every two to three years. It is a mandatory task for farms in derogation.Soil samples cost approximately €20-30 per sample. A soil corer costs approximately €80 to purchase.Soil tests should be taken as late as possible after the last application of lime, P or K to avoid skewing the test results. Therefore, November to February are the best months in which to test. Make sure to take samples before spreading slurry this spring.Do not sample for two years after a lime application and three months after P or K application. Nitrogen spreading does not affect soil sample results.Each soil test should represent between 2-4ha of grassland.Use a soil corer – P will build up in the top 2-3cm of the soil so it is important to take a core over 5cm in depth.Take samples in a fashion that give a fair reflection of the designated area – best practice is to walk in a W-shaped pattern across the field.Avoid any unusual spots such as drinking troughs, dung patches, waterlogged areas, etc.Take 20 to 25 cores per sample.Remember to ID each sample box and correctly correspond each sample ID with the area sampled – it is best to write the ID on a map of the farm. 
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