At this time of year, most farmers start counting out how many more days they can get at grass.

Feeding more meal, introducing silage and housing by day or by night are means of extending the grazing season. The question is, how do you know when to do all or any of these things?

For some farmers all of these things are somewhat academic, as how long more they will get at grass is all governed by the weather. With heavy rain forecast for early this week, housing, perhaps temporally will not be too far away.

Grass availability

For the majority of dairy farmers, the decision to feed more silage should be made based on grass availability.

There are two ways of doing this. The first and most accurate is to look at average farm cover. This tells you the total amount of grass on the farm and averages it per hectare.

The objective is to close the farm up at an average farm cover that will provide enough grass for cows in early spring.

This can then be compared against targets set by the grass budget. In the budget, grass demand in February and March, along with expected growth rates are estimated. The objective is to close the farm up at an average farm cover that will provide enough grass for cows in early spring, with minimal concentrate.

The objective of the autumn budget is that the farm will build up enough grass so as to keep cows out grazing with minimal supplement in late autumn.

At this stage, that’s in the past and farmers either have enough grass now or they don’t. The actual target will vary from farm to farm but the target closing cover on 1 December is usually between 600 and 900kgDM/ha.

Most farmers will house their cows fully in mid-November, meaning there will be two weeks of growth with no offtakes before 1 December. Therefore, average farm cover can be close to or below target closing cover in late October and still be on target by 1 December.

Key step

The key step is to work out your own budget to understand your own targets and then take the correct action. If the budget says you won’t meet your target then you need to increase supplement now or else be prepared to house cows earlier than planned.

Just looking at days ahead and ignoring average farm cover is a less desirable approach as you could be doing this at the expense of not having enough grass next spring.

Spring grass is far more valuable than autumn grass, both in terms of feed value but also from a labour saving point of view.

The key point is not to be afraid to put in more supplement now if needs be. This can be done in the form of silage or extra meal in order to keep cows at grass for as long as possible, but not to deplete average farm cover for next spring.