Getting more value from their effluent was the motivation for a change in farm practice for Morrinsville dairy farmers Nick and Wendy Vollebregt. ‘We had always used the traditional pond system on our farm, pumping them out every second year, so with us having to put in a new system for our new dairy shed we decided to invest in a total effluent management system’.
‘We understood the nutrient value of effluent back onto pasture and discussions with the regional council made us very aware that we needed to invest in a future proof system. We are milking 230 cows and we were keen to ensure that we got a return on our effluent investment so we worked in with Hi-Tech Enviro Solutions to design, manufacture and install our new system, which includes a DODA effluent pump and stirrer, a 64,000-ltr pre-cast tank, hydrant line and an irrigator.’
‘Our new system is scalable and in stage one we have covered 11 paddocks of 1.5 hectares each and our aim is to increase the irrigated areas to another 5 paddocks which would mean a good portion of our farm will be irrigated.’
‘We installed our new system in June and while it is early days, the new irrigated areas have performed well and we are certainly pleased with our investment.’
Brian Crowe stressed that dairy effluent is a source of nitrogen and trace elements that can increase pasture production. In addition the organic matter contained within it will also improve soil water holding capability, soil aeration, drainage and soil tillage characteristics. Research is showing that 100 cows will produce approximately 590kg per year of nitrogen back into the soil if spread on paddocks.
To get started, farmers need to work on irrigating around 4ha per 100 cows then grow their systems from there. For best management, irrigate paddocks just after cows have grazed, keeping records of when each paddock is irrigated to allow for the right rotation cycle for the ground.
The composition of effluent will vary according to time of year, cow diet, and the amount of dilution. Regular testing is advisable. This allows fertilizer applications to complement irrigation, making for optimum use of both systems. The bottom line being fertiliser savings will help alleviate the cost of extending the system across as much of the farm as is practical.
