The slurry spreading period is set to open in the coming weeks, and so farmers should be testing slurry in the yard and get an understanding of the value of their slurry.
Farmers need to appreciate the value of their cattle slurry produced on the farm and make appropriate decisions this spring in order to ensure the best growth response is achieved.
Slurry should be treated in a similar way to chemical fertilisers by timing its application in conjunction with optimum growing conditions to ensure a good response and efficient use of nutrients.
The value of slurry has been estimated to have nearly doubled in the past three to four years, with the price of fertiliser and further restriction on farmers.
At the moment, it can be estimated to be worth around €30-€35 per 1,000/gal if you take into account the nitrogen (N), potassium (K), and phosphorus (P) in it, according to Teagasc.
It should not be underestimated the value of slurry, with around 80% of its nutrient value being in the form of P and K which could prove crucial for farms restricted with P applications.
For farmers with good levels of P in their soil samples already, they won’t have much of an allowance or if in index four for P, they won’t have any allowance.
Testing slurry
As the slurry spreading period edges closer, it is a good idea to get your slurry tested prior to application so you know exactly what nutrients your paddocks are getting.
A Teagasc survey testing slurry across a range of farms produced an average value of 9 units of N, 5 units of P and 32 units of K contained within 1,000gal of cattle slurry.
However, there can be a huge variability in the nutritive content of cattle slurry from one farm to the next or even from one tank on the farm to the next.
Factors such as the slurry’s dry matter (DM), the animals from which the slurry is produced from, the feeding regime of the animals and the exposure of the tank to rain or weather conditions can seriously impact its nutritive value.
Farms that have open tanks with no cover over it is going to have a lower slurry DM and a lower nutrient content, and if the tank is well covered, it generally results in a higher DM and a higher nutrient content.
Slurry testing can allow farmers to target slurry with higher P and K levels to silage ground, whereas slurry with a lower nutritive value can be applied to grazing swards, for which the requirement for P and K is typically lower.
The value of slurry can vary drastically and so testing slurry is a practical step to maximise the efficient use of your organic fertiliser.