Step 1. Planning
The high energy and starch content of forage maize make it a highly valuable silage. But it’s also one of your riskiest forages in terms of preserving it.
With its two opponents knocking on the door of: (1) aerobic spoilage (heating) caused by yeasts and moulds in the presence of air; and (2) risks to fermentation, especially when making greener, moister maize silage – it only takes one slip of management to significantly reduce its feed quality, or the tonnes of dry matter (DM) in your clamp.
Indeed, results from two years of surveys of UK dairy farms suggest there is huge scope for improving how maize silage is made.
For example, while good consolidation and tight sealing were the most common methods used to manage aerobic spoilage (heating) – named by 60% and 77% of respondents respectively in the 2017 survey – this still left a large percentage of producers who weren’t using these important techniques to the full.
When planning your maize harvest, make sure you take the importance of good preservation into account, and that your contractor is lined up for your anticipated harvest date and has the appropriate additive.
If growing modern, ‘stay green’ varieties, they should not have died off (or dried off) by the time they are harvested.
For good quality silage at an acceptable yield, cut just before heading.
Similarly, although it might be tempting to cut low as this increases yield, the stem base is the part of the plant with the lowest digestibility. So again, overall quality will be improved by cutting higher.
On top of that, dead material in the sward base contains higher levels of undesirable micro-organisms that hinder fermentation and increase aerobic spoilage.
And cutting too low increases the risk of introducing soil micro-organisms, such as clostridia, into silage, increasing the risk of a poor fermentation and reducing it's feed value, or even potentially contaminating with listeria.