For some farmers, the winter has already begun because ground is just too wet for grazing. But for the majority, the end of grazing is close, because they are running out of grass. The term ‘running out of grass’ is not quite accurate to describe why the best grassland farmers house stock. They house stock in early November because they want to keep grass for the spring, as opposed to grazing everything in late autumn and early winter. There could be an extra three or four weeks grazing available at this time of year before they would literally run out of grass. The reasons for carrying grass over and into next spring have been well documented, but are worth repeating:
For some farmers, the winter has already begun because ground is just too wet for grazing. But for the majority, the end of grazing is close, because they are running out of grass. The term ‘running out of grass’ is not quite accurate to describe why the best grassland farmers house stock. They house stock in early November because they want to keep grass for the spring, as opposed to grazing everything in late autumn and early winter.
There could be an extra three or four weeks grazing available at this time of year before they would literally run out of grass. The reasons for carrying grass over and into next spring have been well documented, but are worth repeating:
Grass has a much higher feeding value in spring so animal performance is much better.Freshly calved cows eat less grass, so a field of grass at the same cover will last longer in spring.Days at grass is worth more in spring than autumn.Spring grazing reduces the workload. When to stop grazing
So, how do you know when to stop grazing in late autumn? It goes without saying that the weather forecast has a huge bearing on the decision. The forecast for this week is not good so that will make the decision for a lot of farmers.
Weather aside, it is average farm cover that the best grassland farmers use to help make the decision. The average farm cover is the average amount of grass on the farm. It’s calculated by adding up all the grass on the farm and getting an average.
Most farmers would like to open at between 900 and 1,200kg of average farm cover in spring
When the target closing cover is met, then cows should be housed. The target is determined by what you need to open at next spring.
Most farmers would like to open at between 900 and 1,200kg of average farm cover in spring. The higher the demand for grass is in spring, the higher the target should be.
When you know the opening target, the closing target can be worked out by subtracting what you expect to grow over the winter, typically three to four kilos of dry matter per day on average between 1 December and 1 February.
This will give you the target closing cover for 1 December, usually between 650kg and 950kg/ha. Some farmers will go lower than this in November and then house, meaning average farm cover will catch up to target in late November.
This is a very scientific way of assessing grass covers and of course there are things that can happen that can throw it out. But it is beyond doubt the best way of helping farmers to make informed decisions.
So, farmers should measure grass this week and next and then make a decision about whether they should stop grazing, slow down grazing or keep going full-time for another while.
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