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Maximising your second-cut silage

Weather conditions for first cuts this year were optimal, with an exceptionally dry end to April and through May.
But most farmers will agree that pit size is back 10-15 per cent on previous years due to a soil moisture deficit which held back grass growth post fertiliser application.
However, while the physical yield is reduced, the quality of the silage is most likely to be higher than 2024, which, as we remember, was a wet and challenging year for first cuts – this reduced dry matter (DM) and overall quality.
As the weather has changed in the last number of weeks and we are experiencing ‘normal’ precipitation levels, it is important that we think about a strategy for cutting second-cut silage in the coming weeks. For many farmers, a good quality second cut is essential and a last chance to secure enough top-quality grass silage for winter. As silage is the second cheapest feedstock after grazed grass, making good-quality second-cut silage is of paramount importance. High dry matter digestibility (DMD [70+]) silage consistently returns higher margins over purchased feeds.
Avoid the temptation to chase for a very bulky second cut; as with the first cut, quality is key. This is important because after grass begins to head, forage DMD falls by 0.5 per cent per day. Therefore, it’s essential to monitor growth regularly to ensure you cut at the optimum time to balance quality and yield. We have no crystal ball to know what the weather will do in the autumn and into winter and spring. Will there be a grass shortage due to a cold, wet spring, or a summer drought, or a challenging autumn? Who knows? So, having more of a high-quality home-produced silage is critical to keep animals performing in all eventualities. Generally, second cut is five to six weeks after the first cut, depending on the weather.

Five top tips to making second-cut silage

1. Cutting height
Even if the day is warm, the day length is shorter after June 21, and this must be accounted for in the cutting height. Set the mower 8cm from the ground in order to leave the stem in the field. This will also allow increased airflow and speed up wilting time. Leaving a higher residual also helps if ground is wet or soft, as the mowed grass will be higher off the ground, thus reducing soil contamination. Cutting a little higher will also speed up regrowth for subsequent silage cuts or grass.

2. Wilting
Aim for 30 per cent DM and a wilting time of no longer than 24 hours, depending on weather. Otherwise, the speed of sugar losses will be quicker than the speed at which moisture is lost, and the result will be higher losses and poorer silage fermentation. Forecasts are looking good for the end of June into July, so monitor and wilt according to the windows of favourable weather conditions.

3. Chop length
If the second cut is being ensiled in a clamp and the DM may be low due to wet weather conditions or insufficient wilt, we must consider at what length the grass is being chopped by the harvester. There is a risk of the clamp slipping if grass is of high moisture and chopped too short. Clamp slippage is a risk to health and safety and increases silage waste. When grass is below 25 per cent DM, it is advisable to chop longer at 12cm. Above 25 per cent DM, a 10cm chop length is preferred.

4. Additive use
Egalis Ferment, developed by Alltech, is an inoculant that will act to maximise the quality of all grass silages. The Egalis range acts to secure a very fast pH drop within a clamp; the result is lower DM losses and maximum nutrient retention, both within the clamp and at feed out. As a result, farmers will have greater quantities of better, more nutritious silage to feed and fewer concerns about wasting feed.
At a fundamental level, Egalis controls and drives forage fermentations using highly efficient homolactic bacteria and elements that inhibit fungal growth. This inoculant range brings together Alltech’s decades of expertise in fermentation, utilising bacterial strains specifically selected to maximise nutrient and dry matter protection. Egalis was developed by Alltech and independently trialled over a significant period.
The Egalis grouping of products includes inoculants that meet the specific needs of farmers and contractors committed to making high-quality grass, whole crop and maize silages. However, Egalis Ferment is specifically suited to maximise the quality of grass silages. It is comprised of one million homofermentative bacteria (Lactiplantibacillus plantarum and Pediococcus pentosaceus), which work synergistically to rapidly lower pH to the required final pH, irrespective of the dry matter content or the buffering capacity of the forage.

5.  Ensiling second-cut silage
Preferably, second-cut should go into its own clamp, but not all systems may permit this due to space restrictions. If managed correctly, it can be put in the same pit as first cut; however, you need to take the appropriate precautions.
When opening the first-cut pit, it is critical to prevent spoilage by minimising the ingress and quantity of air entering the pit. When removing the first-cut cover, wait as long as possible where applicable just before second-cut silage starts to arrive in the yard, keeping the first-cut silage unexposed to aerobic spoilage. Treat plastic carefully to avoid any holes, tears or damage, and make sure that there is sufficient plastic for the new volume of silage in the pit.