As spring barley crops are appearing across the country, farmers have been and will be applying nitrogen (N) to these crops in the coming days.

Spring feed barley

Crops destined for feed barley can receive up to 135kg N/ha and a further 20kg of N/ha for every 1t/ha achieved over 6.5t/ha.

Spring malting barley

Those growing malting barley shouldn’t change a whole lot from their normal regime, unless crops were sown a lot later than usual.

Some farmers front load crops with N in the seedbed. Others will go now that the tramlines have emerged. The earlier the N goes on the better.

Teagasc trials from the past have shown that protein content reduces by 0.2% per 10kg N/ha reduction in N rate. Therefore, it is important to look at previous protein results and gauge the N rate accordingly.

Spring wheat

Spring wheat crops on index 1 soils can receive 160kg N/ha and crops on index 2 soils can receive 130kg N/ha. Soils on index 3 and 4 go down to 60kg N/ha.

For every 1t/ha achieved over 7.5t/ha an extra 20kg N/ha can be applied.

Spring oats

The N limit on spring oat crops on index 1 soils is 110kg N/ha before any proof of past yields are shown. Index 2 soils may receive 90kg N/ha, while index 3 and 4 soils may receive 60kg N/ha and 30kg N/ha respectively.

The table below shows the N limits for cereal crops according to the soil N index system.