Autumn has arrived, as has the rain, so it is now that farmers must look at spreading the last of their chemical nitrogen (N) for 2022.
The amount of chemical N spread on farms is likely greatly reduced compared to other years, due to a number of factors including the cost of it and the drought-like conditions experience in many parts of the country.
Grassland
Now that the rain has arrived in the majority of areas that were affected by drought-like conditions, farmers will be wondering which is now the best approach for applying N fertiliser on grassland.
In many areas it has been a number of weeks since chemical N has been spread on paddocks.
With the cost of chemical N being so high in 2022, it is important that if any N is spread, there is a benefit obtained from it.
Chemical N
According to Teagasc, it is essential that a balanced approach be taken, which will help to meet forage requirements and avoid losses of N to water.
There are a number of factors that need to be considered according to Pat Murphy, head of environment knowledge transfer at Teagasc.
The lack of grass growth over the last number of week has meant that the supplementary feeding of animals has taken place. This has resulted in many farms using fodder that was meant for the winter months.
Because of this, grazing rotation length should be extended to greater than 30 days and supplementary feeding should be continued where grass covers are low, in order to build up covers on the farm.
On lower-stocked farms, there may be sufficient N in the soil to meet requirements, provided rotation length is extended.
Where there is the demand, it is recommended that 15kg to 25kg of N/ha (12-20 units/ac) be applied immediately on grazing land.
Slurry
Your preference should be to apply slurry/soiled water, where available, which should be applied immediately to replace artificial N.
The use of low emissions slurry spreading (LESS) technology will facilitate earlier grazing and get the maximum value from the N in the slurry/soiled water.
It is important to remember that the closed period for slurry application this year begins on October 8, which is one week earlier than 2021.
Given that we are now in September, growth rates are falling due to reducing day length and care is needed to match N application with potential uptake of N by the grass crop.
Pat also suggested that farmers look at the winter feed supplies on farms and complete a fodder budget ahead of winter period on farms.
He also remined farmers that the closing date for application of artificial fertiliser is Wednesday, September 14.