Often thought of as just waste, the effluent from dairy cows is rich in nutrient resources and it is worthwhile managing these nutrients as efficiently as possible.

Ravensdown Analytical Research Laboratories Manager Michael White said knowing what is in the effluent can also make it easier for farmer to ensure they are operating within the requirements of their resource consents, in terms of knowing how much nitrogen can be applied per hectare.

"For example, if you know how rich the effluent is, you can work out what area is appropriate to spread it over to remain within these conditions."

He pointed out the other main reason to get farm effluent analysed is to ensure you are maximising the nutrient value within your dairy effluent.

"Nutrient budgeting programmes tend to give generic figures to work with, but it's worth having a figure more particular to a given farm situation to help with management decisions.

"Research has shown the nutrients in effluent can be worth around $NZ290 a hectare, so there's a fair amount of value in there."

The composition of effluent varies a lot ... it's typically most nutrient-rich during spring ... it also varies with the feed animals are eating.

Source: FarmNews.co.nz