Poor weather across the island has left many farmers facing a very bleak winter, with significant numbers already concerned that they will run out of feedstocks.

Stark results from an AgriLand poll, of around 1,000 farmers, has found that almost 40% do not have enough fodder to get them through the dark months ahead.

As part of the survey, farmers were asked two questions: Have you got enough fodder to get through the winter period? If you expect to be short of fodder this winter, what part of the country are you in?

More than a third of recipients who said they “did not have enough silage” were based in the west, followed by around a quarter who were based in the south of the country.

The wet summer has had a double blow for farmers this year with the loss of much of the country’s third and fourth cut silage. At the same time, cattle housed earlier than normal have already started eating into winter feed supplies.

In Northern Ireland, the Department of Agriculture, Environment and Rural Affairs (DAERA), has advised farmers to act now to assess the quantity, and quality, of fodder so they can plan ahead.

Assessing quantity – pit silage

Farmers can use the DAERA online calculator to complete the calculations, or manually work them out using the example below. You’ll need to know what size your silage pits are first.


A silo measuring 20m long and 10m wide, filled to an average depth of 2.5m, has a volume of 500m³ of silage.

The dry matter of this silage will also affect tonnage. To calculate the fresh weight of your silage, multiply the volume of your silage, by the figure in the table below which best relates to the dry matter of your silage.

Conversion from cubic metres to tonnage of fresh weight silage

Calculating silage store for the winter

Round Bales

The calculation is a little bit more complicated for round bales, as bales can vary in quality.

Dr. Alastair Boyle, dairying technologist at the College of Agriculture, Food and Rural Enterprise (CAFRE), advises weighing the bales.

He said: “Round bales can vary considerably in both weight and quality. Taking time to weigh a representative sample will enable a more accurate assessment to be made of the tonnage available.

“Remember that dry silage contains more nutrients per tonne; water has no nutritive value.”

Assessing the demand of the livestock

Again, the online calculator can be used to complete this, or manual calculations can be done using the figures in the table below.

Monthly silage intakes of various livestock categories

Calculating silage requirements for the winter

Boyle advises that assessing the quality of your silage can be as important as the amount available.

Assessing quality

He said: “An analysis of the silage will give a prediction of the silage intake potential; and likely output in terms of live weight gain or milk production. The dry matter; digestibility; energy; and protein content are all measured and the quality of the fermentation assessed.

“Silage analysis is relatively inexpensive and will enable you to feed your livestock more accurately to achieve the required performance.

“It can be completed within a few days in a laboratory such as the Agri-Food and Biosciences Institute (AFBI) in Hillsborough, Co. Down, or in a few minutes on the farm using the latest hand-held scanning equipment. Contact your feed company or development adviser to arrange a test.

“A good representative sample should be analysed in all situations; bales or pits should ideally be sampled on several occasions during the winter,” he said.

Supplementation and Alternative Feeds

If silage stocks are limited the department advises considering supplementing, or using alternative feeds.

Dry cows can be fed 3kg of rolled barley and ad-lib straw. However, this diet is protein deficient.

Soya hulls can replace up to 30% of the silage in the diet and are a good high-fibre, safe feed, for suckler cows. However, availability can be a problem.

Fodder beet can replace up to 30% of the daily silage requirement of cows, young stock and finishing cattle. However, it contains low protein; growing cattle should be fed a protein supplement.

Potatoes can replace 20-25% of the daily silage requirement and have a higher protein content (11%) than fodder beet.