Control what you can and manage the rest as it happens – this will be the goal for most dairy farmers this silage season. Making good-quality silage is dependent on a number of outside factors – silage contractor availability, weather, soil fertility, etc.

However, there are number of factors that you control to help silage quantity and quality. Reduce weather risk and maybe the best option will be to cut half the crop now so that: (1) at the very least, you reduce the risk or making all bad silage; (2) you make some good-quality silage and/or (3) you limit field damage.

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The basics still apply – cut, dry, wilt if possible and cover as quickly as possible.

One of the key factors is to ensure bag nitrogen has been out long enough. The old rule of thumb that works in most normal growing years is a silage crop will use two units of nitrogen per day. That means if 80 units of nitrogen were applied on 20 April, it is 40 days (end of May) before all nitrogen is used by the crop.

Already farmers have harvested silage crops that were grazed in late March and spread with nitrogen shortly after that. Wilting is one tool you can use to help reduce silage nitrogen and increase sugars if you feel you have to cut a few days early.

If you can, leave the crop wilt for 24 hours – any longer and you start to lose energy in the crop. On average, trials show you will increase dry matter by 4% to 5% for every six hours of drying. Spread out over the surface of the field to maximise the drying you get.

1 Seed heads in silage crop: Aim to cut silage crops before seed heads have appeared. As soon as seed heads appear or crops start to lodge, the quality of the crop is going down. The challenge is to strike a balance between quality and quantity.

2 Cut dry but leave standing in wet: Research has shown that rain wets a standing crop much more than a cut crop but a standing crop will dry out faster. Research also shows tedding out a silage crop will increase wilting rate but repeated tedding has minimal effect. Spread out the crop across the field if possible to increase wilting rate.

3 The majority of Irish cows calve in the spring and compared to 10 years ago the amount of silage fed to calved cows is much reduced. With some farmers planning earlier and later milk supply in a no-quota world, then maybe round bales or a small pit away from the main pit might help options.

4 Pit management: The aim is to achieve air free conditions as quickly as possible. Quick filling of the pit ensuring the grass is well compacted, covered and sealed by at least one new sheet and a second re-used or new sheet followed by fully covering the pit with tyres and sandbags is paramount.