With muck now viewed as valuable fertiliser rather than a waste product, slurry application is becoming something of a science. But getting high volumes of liquid onto fields can be tricky if surface run-off is to be avoided. Disc injectors offer a lot of potential in improving soil penetration and in placing nutrients right in the rooting zone. However they do restrict output when compared to conventional splash-plates and dribble-bars.
To answer that conundrum, in recent years a number of UK firms have adapted grassland spike aerators to apply slurry either off the back of a tanker or as part of an umbilical system. As with any dribble-bar or trailing shoe set-up, a macerator and distribution head are required. Such kit is expensive and has a high maintenance requirement. Also the narrow-bore pipework that tends to be used to deliver liquid to the outlets can be prone to blockage.