For fear of sounding like a broken record, 2024 will go down as one of the toughest ever for grass and fodder.
What really aggravated matters was the poor summer of 2023 leading to some grass not being harvested and an early housing date. The net result is that surpluses from last year were used up in the majority of cases, and fodder is tight on a lot of farms.
The most critical priority now is to identify any deficits early on as this will give greater options to adjust feed budgets or stock numbers. Looking at an empty pit in mid-January could be a costly affair, so take the time to measure silage stocks now and plan on what to do.
Pits are well settled now, so it is relatively easy to calculate the size of them using Table 2 below. Pits will generally be sloped from the front upwards (where the grass was pushed up), which will need consideration when calculating the size. A general guide is to calculate how far back the front slopes (eg 4m) and divide by two (2m). This should be used instead of the actual length of the pit to better calculate volume.
The slope of the pit sides also need to be factored in when calculating pit volume. Where a pit is 10m wide and each side is sloped up from the wall 0.75m in to the pit, then this volume needs to be subtracted from the overall volume.
Case study
Robert has a pit which measures 9m in width (W), 30m in length (L) and has an average height of 3.2m (H). The pit reaches full height 4m from the front of the pit. It has 2.5m high walls on both sides.
To calculate the capacity of the pit we measure L x W x H, taking note of the earlier rule for calculating the slope at the front, meaning our working length is 28m. This calculates as: 9m x 28m x 3.2m =806.4m³.
The above calculation can be completed in
Table 2, once the adjustment for the slope at the front of the pit is made to the length. However, we need to calculate the lost capacity of the slope up from the sides as well, with the pit reaching full height at 0.75m on both sides.
Since the pit is sloping from both sides (meaning the two wedges create a rectangle) we will be simply able to multiply 0.75m by the pit length (26m as the pit only reaches full height from that point) by the height over the wall (0.7m). This calculates as: 26m x 0.8m x 0.75m= 15.6m³
This figure should be subtracted from the overall pit capacity, in this case: 806.4m³ -15.6m³ = 790.8m³
While it may not seem like a lot of silage, accuracy is important where supplies are tight.
How to correct a fodder deficit
If a fodder deficit is identified, then there are a number of options a farmer can avail of to correct it, and every option needs to be closely examined to see if it is the right fit for you.
Option one: purchase additional fodder
This is possibly the option with the most variables. Can good fodder be sourced within the locality at a reasonable cost? Most fodder will be in wrapped bale form. If possible, get a feed analysis done on some of the silage, even if it is at your own cost.
Silage in the low 60s on DMD will do little in terms of weight gain, and spring calving cows may struggle to hold body condition score on it.
It may be a case of targeting your own higher quality feed at youngstock or autumn-calved cows and feeding some lesser quality purchased silage to spring calvers. There is also the option of stretching out good quality silage by mixing in straw or hay for additional fibre.
Both are good options for rumen fill, meaning where high DMD silage is being fed to spring calvers in good body condition, then the silage can be limited.
Option two: purchase and feed additional concentrates
Where there are forward type stores on the farm, an effort can be made to finish these with a short, intense high concentrate diet. Cattle should be built up incrementally with feed, but up to 7-8kg of concentrates can be fed to finishing bullocks, heifers or cull cows, with high quality silage being fed as well.It is important that the feed is built up gradually and that feeding is split across two to three feeds where high levels of concentrates are being fed.
Option three: sell stock
Where cash reserves are tight, this might be the most attractive option to a farmer. Store cattle are a solid trade at the minute, so offloading some now and focusing on a smaller batch of cattle to bring through to finishing using your own fodder might be a better option.
Empty spring calvers will fall in to this category as well, so if scanning hasn’t been complete, this should be done as soon as possible, with empty cows drafted as opposed to being finished on farm if fodder stocks are tight.
Many farms are tight on fodder this year, with early intervention being critical to address deficits.Calculate silage stocks and requirements on farm as accurately as possible.Where there is a deficit identified, purchasing fodder, feeding additional concentrates or selling stock live are options.
For fear of sounding like a broken record, 2024 will go down as one of the toughest ever for grass and fodder.
What really aggravated matters was the poor summer of 2023 leading to some grass not being harvested and an early housing date. The net result is that surpluses from last year were used up in the majority of cases, and fodder is tight on a lot of farms.
The most critical priority now is to identify any deficits early on as this will give greater options to adjust feed budgets or stock numbers. Looking at an empty pit in mid-January could be a costly affair, so take the time to measure silage stocks now and plan on what to do.
Pits are well settled now, so it is relatively easy to calculate the size of them using Table 2 below. Pits will generally be sloped from the front upwards (where the grass was pushed up), which will need consideration when calculating the size. A general guide is to calculate how far back the front slopes (eg 4m) and divide by two (2m). This should be used instead of the actual length of the pit to better calculate volume.
The slope of the pit sides also need to be factored in when calculating pit volume. Where a pit is 10m wide and each side is sloped up from the wall 0.75m in to the pit, then this volume needs to be subtracted from the overall volume.
Case study
Robert has a pit which measures 9m in width (W), 30m in length (L) and has an average height of 3.2m (H). The pit reaches full height 4m from the front of the pit. It has 2.5m high walls on both sides.
To calculate the capacity of the pit we measure L x W x H, taking note of the earlier rule for calculating the slope at the front, meaning our working length is 28m. This calculates as: 9m x 28m x 3.2m =806.4m³.
The above calculation can be completed in
Table 2, once the adjustment for the slope at the front of the pit is made to the length. However, we need to calculate the lost capacity of the slope up from the sides as well, with the pit reaching full height at 0.75m on both sides.
Since the pit is sloping from both sides (meaning the two wedges create a rectangle) we will be simply able to multiply 0.75m by the pit length (26m as the pit only reaches full height from that point) by the height over the wall (0.7m). This calculates as: 26m x 0.8m x 0.75m= 15.6m³
This figure should be subtracted from the overall pit capacity, in this case: 806.4m³ -15.6m³ = 790.8m³
While it may not seem like a lot of silage, accuracy is important where supplies are tight.
How to correct a fodder deficit
If a fodder deficit is identified, then there are a number of options a farmer can avail of to correct it, and every option needs to be closely examined to see if it is the right fit for you.
Option one: purchase additional fodder
This is possibly the option with the most variables. Can good fodder be sourced within the locality at a reasonable cost? Most fodder will be in wrapped bale form. If possible, get a feed analysis done on some of the silage, even if it is at your own cost.
Silage in the low 60s on DMD will do little in terms of weight gain, and spring calving cows may struggle to hold body condition score on it.
It may be a case of targeting your own higher quality feed at youngstock or autumn-calved cows and feeding some lesser quality purchased silage to spring calvers. There is also the option of stretching out good quality silage by mixing in straw or hay for additional fibre.
Both are good options for rumen fill, meaning where high DMD silage is being fed to spring calvers in good body condition, then the silage can be limited.
Option two: purchase and feed additional concentrates
Where there are forward type stores on the farm, an effort can be made to finish these with a short, intense high concentrate diet. Cattle should be built up incrementally with feed, but up to 7-8kg of concentrates can be fed to finishing bullocks, heifers or cull cows, with high quality silage being fed as well.It is important that the feed is built up gradually and that feeding is split across two to three feeds where high levels of concentrates are being fed.
Option three: sell stock
Where cash reserves are tight, this might be the most attractive option to a farmer. Store cattle are a solid trade at the minute, so offloading some now and focusing on a smaller batch of cattle to bring through to finishing using your own fodder might be a better option.
Empty spring calvers will fall in to this category as well, so if scanning hasn’t been complete, this should be done as soon as possible, with empty cows drafted as opposed to being finished on farm if fodder stocks are tight.
Many farms are tight on fodder this year, with early intervention being critical to address deficits.Calculate silage stocks and requirements on farm as accurately as possible.Where there is a deficit identified, purchasing fodder, feeding additional concentrates or selling stock live are options. 
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