Forage quality is the biggest bottleneck on many farms, with every attempt made to improve the cheapest feed on the farm. Maximising milk production from whatever land you have available to you must be achieved to ensure sustainable margins from dairy production. For this reason, there has been a shift to more frequent and lighter cuts of grass silage, cutting every month through the growing season. The multi cut technique can be the holy grail of increased quality and a higher overall annual yield. With the monstrous appetites of modern grass harvesting equipment, it makes the most of short weather windows, producing rocket fuel silage. Sounds simple, but in practice, there can be some pitfalls that need to be avoided to fully utilise the technique. As we look back on the season gone, here are a few pointers to help make the most of the 2018 harvest season if you're thinking of trying a multi cut system.
Although by using a multi cut system there is a greater chance of a consistent product, care must still be taken to ensure this - with dry matter being the hardest things to maintain consistently. The more cuts scheduled throughout the season, the more weather windows are needed and increases the chance of being caught out by the weather. To overcome this, be as prepared as possible by having the kit on hand to complete the operation fast, without compromising quality. With lighter cuts, dry down can be rapid on hot days, so be ready to get it in the clamp before the crop wilts away in the summer sun.
To best manage wilting and make the most of the quality in the grass, the best harvest practice is to start cutting in the morning as soon as (or not long before) the dew has lifted - so around 9am. Grass dries significantly faster if you move it, so aim to get the tedder in the field within 3 hours of cutting. By cutting in the morning and tedding it, you will maximise wilt within the first 6hrs, utilising the heat of the midday sun. After 6hrs, the grasses pores begin to close in self-defence, slowing the rate of wilting. A morning cut approach is far better than evening, where the grass sits on wet soil all night rotting rather than wilting.
Ted the crop again before getting the chopper in that afternoon, unless it’s a very hot day. This will ensure consistent results, preserving the maximum amount of energy from the grass and is only really possible with light cuts associated with this method of frequent cutting.
Grass quality deteriorates as the year progresses. Even if management remains consistent, with every attempt made to keep the fourth cut as good as the first, it unfortunately will not be. This is due to the natural behaviour of grass species increasing NDF and the reduction day light hours after the summer equinox. You will not beat it however hard you try, so keep your herd’s feed as consistent as possible by layering grass in the clamp instead of wedging it. Layering the grass thinly along the full length of the clamp promotes increased rolling and keeps tractors on the pit more level - if the angle of slope gets more than 15 degrees, the effectiveness of the rolling substantially reduces.
Finally, consider young silage a different crop to more mature grass silage, as there is a vast difference in the way it feeds, along with the potential milk levels from it. By taking the crop younger, the fibre element to the silage is less, moreover, the fibre present is degraded in the rumen much faster than mature silages. Young grass silage tends to be very acidic when wet, due to the high sugar levels that have been fermented into lactic acid. Although palatable and a good energy source for the cow, it can cause rumen stability issues if not correctly factored. Another consideration that should be common for such silages surrounds the high oil levels, contributing to milk fat depression, need different diet raw materials to counter act its affect. Grass silage in its most potent form blurs the lines between a forage and concentrate as it can be so energy rich.
Producing high volumes of high energy dense silage with a multi cut system provides an opportunity to maximise margins further than ever by reducing the cost of bought on feeds. Equally it presents new challenges that must be managed for this system to prosper. A well-considered and managed approach will ensure that pitfalls are avoided, and opportunities maximised.
Mark Price
Dairy Specialist
You can follow Mark on Twitter @m_priceo or contact the Dairy Team here.
