Risk-free slurry spreading and soil improvement in just one pass

Applying slurry to grassland using splash-plates may be a relatively cheap and quick method, but there is a higher nutrient loss through evaporation and greater risk of run-off compared to the more accurate injection systems.

So when Tiverton beef farmer Josh Reed, decided to diversify the contracting business he runs with his father Stuart, he not only bought a conventional umbilical system, he also invested in a combination grass slitter and slurry injector system.

Josh explains: “With splash plate application, you are limited by pressure, and as there are only two outlets, there’s a limit to the volume of slurry spread at a time.  I’m also conscious that splash plates have been banned in some European countries, and one day it might happen here. So I wanted to get ahead of the game and have an alternative applicator in-hand.

“I saw OPICO’s two-in-one 6m Slit Injector at the LAMMA machinery show in 2014. It consists of a sward slitter for aeration and an umbilical spreading system with an applicator that dispenses slurry close to the ground where much of it falls into the holes left by the spikes of the slitter.

“Because the slurry is delivered close to the ground, I can rely on the GPS autosteer to get an even application across the field whereas with the splash plate, I had to judge it by eye. Now, every line gets the same amount of slurry, and there is no wind-blown overlapping.

“I’ve also had no problems with any run-off, and it’s a lot less smelly too!”

Every livestock farmer needs to make the most of their ‘free’ farm yard manure and slurry fertiliser. For organic farmers it is even more key.

At High Down Farm at Bradninch outside Cullompton, organic farmer Graham Vallis milks 170 crossbred cows on an extreme grazing system. Cows only receive supplementary feed for the first 3 months of lactation, typically, 200kg of home-grown cereals and soyabean meal. Yields per lactation reach 4,000-4,500 litres depending on the season.

Graham explains: “Our cows are turned out mid-February and will remain at grass until just before Christmas. So we get compaction in the top few inches of soil from the grazing cattle, and need to aerate the ground using a spiker.”

Grass slitters and aerators will remove shallow compaction in grassland. By slitting/spiking the top 25cm of ground, air can get down into the soil. This stimulates grass growth as oxygen can get absorbed by the roots; slitting will also help dry grazing land out in the spring.

In mid-February of 2014, Josh had spread slurry using the conventional splash plates onto half of a 32 acre field on Graham’s farm. He ran out of time to finish it and returned a few weeks later, this time with his new slit injector.

Graham explains: “To start with, we saw no difference between the two halves of the field. But by autumn, the spiked half had more clover and also more worm casts, indicating a better soil structure.”

Graham was also keen for his slurry to be applied using the injector system, recognising that some fertiliser value is lost in the air with splash-plate systems. Run-off of slurry into watercourses was also a concern, as the farm has some very steep land, most of which is permanent pasture.

Last year, just after one of the hilly fields had been slurried with the slit-injector, there was a cloudburst.

“Afterwards, I went to the stream at the bottom of the field expecting a nightmare,” says Graham. “But it was crystal clear still. The spiking of the ground had kept the slurry in the field. I wouldn’t dare have a splash plate on these fields now.

“Altogether these experiences have given us a lot of confidence in the system, we are having more cloudbursts now, and so we have all the land slit-injected every year.”