How can we reduce our greenhouse gas footprint, not tomorrow when regulators have deemed what is acceptable, but right now? That's the question on the tip of every dairy farmer's tongue.

The good news is many farmers are taking action and, according to experts in the field, there are plenty of options at farmers' disposal that have been scientifically proven to work.

One, possibly the best of them all, unbeknownst to many farmers, is already being extensively used. Farm Systems and Environment Science Impact Leader Dr Robyn Dynes said scientific evidence supports a correlation between lowering nitrate leaching and a reduction of farm methane and nitrous oxide levels.

There are, as is often the case in science, exceptions to the rule. But scientists are now confident of what they have long suspected; that running a farming operation with lower nitrate leaching results in the co-benefit of lowering your Greenhouse Gas footprint. It’s only now, after several years of data gathering and research, much of it now published in science journals, that the evidence is demonstrable.

Dr Robyn Dynes said: “Balancing your environmental footprint is good farming practice. The vast majority of farmers get and aspire to that.

“We now know though that changes to improve water quality - reducing nitrate leaching - will reduce Greenhouse Gas emissions. There are exceptions, but the exciting thing is we also know that doing really practical things like reducing the application of nitrogen fertilisers, managing supplementary feeds supplies and homegrown feeds sources, and then adjusting the stocking rate to the lower feed supply also reduces Greenhouse Gas emissions, and that you can offset the subsequent impact on profitability and production by using tools that farmers already know well.”

They include keeping your highest breeding worth cows. Better genetics was always going to be part of farming cleaner and greener. But scientists are now also confident that reducing stocking numbers should not automatically decrease production levels. The key, Dr Dynes says, is maintaining and managing your pasture quality and quantity levels right through spring and early summer, and that when you find yourself in a feed deficit that you maintain the appetite drivers of your cows.

“That extra attention to detail pays off. It’s a balancing act, as it is every year. The crucial period is that calving to balance date phase, balance date being when feed grown exceeds demand from cows. There is a myriad of variables, including monitoring when soil temperatures are high enough for nitrogen application. But with the right advice, farmers should be able to pull the right levers and lower their emissions.”

There are, as with any business, risks. Investing in a feed pad can improve water quality but either lead to no or in some instances an increase in emissions. This is known as pollution swapping. To negate this risk farmers need to make sure their effluent disposal strategies are sound, as they can, if not correctly managed, raise emissions.

“The co-benefits we’ve found are in many instances already being done to meet water quality regulation, and we have data now that’s proving, on both demonstration and commercial farms, to maintain production. We need to keep reiterating the message on optimising the total feed per hectare (feed grown plus supplements) within the wider reality of farming, water quality and Greenhouse Gas emissions targets.”