The high cost of straw and tight supplies available in the latter half of 2023 witnessed many farmers failing to source their normal levels.

Earlier housing has also put additional pressure on straw reserves and, as such, it is important to review supplies on hand to firstly ensure you are not running tight and, if so, to allow maximum time to put alternate plans in place.

Lowland ewes will require approximately 7kg straw for bedding each week to absorb all urine, while the requirement for hill ewes is significantly lower at 4kg to 5kg.

Looking at this in an easier light, a typical 4x4 round bale of straw weighing 14kg will generally be sufficient to provide bedding for 18 to 20 lowland ewes and 30 to 35 hill ewes.

Calculation

This calculation is based on a silage diet. Where hay or haylage is the main diet for ewes, then the bedding requirement may be reduced by 20% to 30%.

It is also worth considering that straw saved this year was of lower quality in places and, therefore, absorbency should not be overestimated.

For users of large volumes of straw bedding, straw choppers or blowers are worth assessing.

Reports vary on the volume of straw that can be saved, with some claiming savings of over 10% while there are very definite savings in labour input.

Lambing considerations

Account also needs to be taken when calculating straw requirements of higher usage during lambing.

Typically, four to five bales need to be factored in for every 100 ewes for bedding lambing pens where ewes are turned out within 24 to 36 hours of delivering lambs.

In high-prolificacy flocks, this requirement should be increased by 20% to 30% to take account of the higher average litter size and need to keep lighter lambs indoors for longer.

Weight of bales

The best way to accurately assess volumes of straw available is by weight, as consideration needs to be given to the variance in weight that can exist between bales.

Round 4x4 bales typically weigh 150kg on average, but well-packed bales can weigh 140kg to 180kg, with poorly packed bales as low as 120kg. The lower moisture content in straw this year will also have an influence.

Rectangular 8x4x3 bales weigh about 360kg (range 350kg to 380kg), while 8x4x4 bales vary more and can weigh from just below 500kg to upwards of 600kg, with an average weight typically of 540kg to 550kg.