How much does your forage maize cost you to grow – including cultivations, seed, drilling, fertiliser, sprays, harvesting and clamping? No doubt it’s worth it. Maize is an energy-rich forage.
But with this size of investment, and knowing it’s a great forage, how much effort do you think should go into conservating it?
After all, you only get one chance to make maize silage correctly. And maize is at the mercy of unwanted bacteria, which interfere with the fermentation, and unwanted yeasts and moulds that cause dry matter and nutrient losses from heating (aerobic spoilage).
Preservation and nutrients
To begin, harvest on time. Too often, maize is harvested late – when leaves are dying. By then, it’s not only past its peak nutritionally, but decaying tissue is a haven for unwanted microbes to thrive.
Instead, maize should be harvested as soon as it reaches 30-33% DM and ideally while leaves are still green. By doing this, it provides a good balance of starch in the cobs, plus living foliage that will have a higher nutritional value and will be easier to consolidate and more digestible to the cow.
In addition, leave at least 15cm of stubble, because the stem base is low in nutritional value. Also, chop short enough to aid clamp consolidation, for example to 1.5-2.0cm. And apply the correct type of additive. Unwanted microbes feed preferentially on sugars and starches, which are precisely the nutrients you want.
For peace of mind, the dual-acting additive, Ecocool, contains the trusted ‘MTD/1’ bacteria found in Ecosyl, which is proven to improve fermentation, combined with a second beneficial bacterium, ‘PJB/1’. This is included to inhibit yeast and mould growth and therefore keep maize silage cool.
Good compaction
When filling the clamp, fill in thin, horizontal layers to aid consolidation, and compact well. A 30% DM crop needs about 25% of its weight arriving at the clamp per hour to be rolling constantly. So 100 t/ hour requires 25t – roughly both a loader and a tractor.
Good compaction is essential to aid fermentation and to starve yeasts and moulds of oxygen. For the same reasons, use side sheets to make clamp walls airtight and an oxygen barrier film on top of the silage, before covering with a well-weighted top sheet and woven sheet.
It sounds like effort, but with volatile milk and feed prices, and potential forage shortages resulting from a dry grass season, maximising milk from good stocks of quality maize silage makes sound financial sense.
Peter Smith can be contacted at Volac on 07920 721955 peter.smith@volac.com