Drier weather is forecast into next week and that is likely to see more farmers taking the opportunity to harvest first-cut silage.

Silage cut in mid to late May is a trade-off between feed quality and quantity. For autumn calving suckler cows or finishing cattle, higher quality silage drives milk yield, fertility and liveweight gain.

For spring calving systems with primarily dry cows carried over winter, silage is more than likely to be cut in early June with aim of getting bulk.

When it comes to silage, a lot depends on weather and availability of contractors. But assuming things go to plan, outlined are some tips to keep in mind.

1. Mowing late in the morning or afternoon

If weather is on your side, farmers with their own kit should consider mowing in late morning, or ideally from lunchtime onwards.

Grass sugars tend to be higher at this point, helping fermentation with lush grass cut in May.

Where a contractor is employed for silage, mowing at these times is rarely an option, as the focus is on completing the job and moving to the next farm.

2. Don’t mow too low

Mowing tight to the ground increases the risk of soil contamination. Aim to leave to a residual around 4cm in height, similar to grazing.

This helps speed up regrowth for second cut and paddocks coming back into the grazing rotation for June.

With red clover swards, increase the mowing height to at least 8cm, thereby avoiding any damage to the crown of the plant.

3. Tedding grass; yes or no?

Tedding is an additional cost and won’t be for everyone. If there is a short window for silage, limiting time for wilting grass, then tedding comes into its own.

Tedding swards will give a rapid wilt, increases the dry matter of lush grass and improved fermentation. Tedding can also improve wilting of heavy swards cut in June.

However, if weather is on your side in mid to late May, and grass can lie for at least 24 hours after mowing, there is little benefit from tedding out swards.

When it comes to red clover silage, tedding should be avoided at all costs, as it causes leaf shatter and increase field losses.

4. Wilting time

The aim with any silage sward should be to raise dry matter to between 30% and 35%. Ideally, keep wilting times between 24 and 48 hours, depending on sun levels and air temperature.

In extremely hot conditions, reduce wilting time to 12 hours for light swards, then rake up into larger rows.

Wilting beyond 48 hours does more harm than good, as extremely high dry matter grass usually leads to poor fermentation.

5. Chop length

Keep chop length in mind as this affects consolidation in the clamp, as well as fibre levels in cattle diets. Aim for a chop length around 8cm to 10cm, which is roughly the width of adult cattle’s muzzle.

Grass chopped below this target length is harder to roll in the pit, leading to more waste and slippage if silage has a low dry matter.

On the flip side, grass that is not chopped is harder to feed out and intakes will be lower, increasing waste silage to scrape out of the feed passage.

Read more

Silage quality and late BISS applications

Keep on top of fly control in heifers and dry cows