What is the value of farmyard manure?

The cattle housing period, on most farms, has been prolonged due to inclement weather. Poor grass growth, coupled with saturated land, has prevented the turnout of cattle to grass. As a result, many farmers will have built up a large supply of farmyard manure (FYM).

However, FYM is only as valuable as the chemical fertiliser that can be saved by using it. According to Teagasc, if farmers are importing organic fertiliser without making adjustments in chemical fertiliser applications, then the organic fertiliser will not be saving any money.

Volatile chemical fertiliser prices in recent years have resulted in equally volatile organic fertiliser value. This can complicate decisions of whether or not to import organic fertilisers onto the farm.

Speaking at a recent Teagasc organic beef farm walk, Teagasc’s Elaine Leavy outlined the benefits of using FYM and other organic fertilisers.

The organic specialist explained that the value of FYM stands at approximately €8-10/t and is the equivalent to a bag of 3:2.5:12.

The table below shows the N, P and K values in manure from a dungstead (decomposed) and FYM (fresh). It must be noted that the values shown in the table need to be adjusted for any costs associated with transport, spreading or storage of the organic fertiliser.

Source: Teagasc

She said: “Good levels of organic matter, good levels of biological activity and good soil structure are as a result of using organic fertilisers. If you maintain these three factors, the minerals and nutrients will be released into the soil and, therefore, encourage growth.

“Farmers can get slurry and FYM analysed to get an indication of what the nutrient content of these manures are.

Image source: Adrian Leech Photography

“With slurry and manures it is very important to know where and when you are going to spread them. They need to be spread where they are required. They are a valuable source of nutrients,” she explained.

Elaine also outlined that keeping soils at a pH that facilitates organic matter breakdown and nutrient recycling is essential for achieving the best results.

The value of various organic fertilisers can be calculated by multiplying the content of valuable plant available nutrients, particularly nitrogen (N), phosphorus (P) and potassium (K), by the chemical fertiliser cost of each element respectively. The chemical fertiliser cost of N, P and K will depend on the price of individual fertilisers.

Furthermore, the most money can be saved when organic fertilisers are applied in relation to crop needs, in order to maximise the nutrients available to the plant.

“Nutrient balance is extremely important. Farmers must try and balance what they have with what they need,” she concluded.