Not much in farming qualifies as natural

21:05, Feb 11 2014
Soil scientist Doug Edmeades
WHAT IS NATURAL?: Using the word "natural" and its derivatives as a benchmark to assess our current and future farming system is nonsensical according to soil scientist Doug Edmeades.

The word "natural" and its derivatives such as "nature's way", "nature's own", "grown naturally", a "product of nature" and "naturally organic" are tossed into product advertising like minties at a lolly scramble.

They convey a feeling that something, a product or a process, is honest and true, as in the way Mother Nature intended, and not artificial or false, in the sense of being man- made.

The implication is always that nature's way is better than man's way or more specifically, mankind has screwed nature and we must now bow our heads in penitential shame.

I thought it was time to play with this idea. Is our clover-based pastoral system natural?

Our pasture species - the many species of forage legume and ryegrasses and all those "weed" grasses like browntop, yorkshire fog and paspalum are all exotic, coming mainly from Europe over 100 years ago. So too our animal genetics - fresians from Fresia, jerseys from Jersey, charolais from France - whether dairy, beef or sheep, are all imported. Sure, we have enhanced them by further selective breeding but they are not natural New Zealand flora and fauna.

Similarly, every farmer in New Zealand, whether Maori or Pakeha, Dutch, Indian, or more recently Filipinos, are visitors to these shores - a point that the late historian Dr Micheal King regularly stressed. Nothing "naturally New Zealand" there, I'm afraid.


Surely there can be nothing more natural than earthworms, those humble blind creatures that work tirelessly for Mother Nature to form soil humus and build our pastoral soils? Guess what - all the useful ones working in our pastoral soils came from Europe. They are also unnatural visitors to our shores.

And by the way, before you wipe those shocked, shaken tears from your checks, remember that these nasty little visitors do terrible things to our soils. They drill holes making it easier for nutrient leaching to occur (nitrate nitrogen loss) and they bring their nutrient rich poo (vermicast) to the soil surface from where it gets washed into streams (phosphorus runoff).

If we are to clean up the environment these critters will need close attention!

You plead; there must be something natural about our clover-based pastoral system.

Ah yes, clover fixes N from the atmosphere and that N ends up going into the soil by way of the soil/plant/animal N cycle. Now that must be as natural as grandma's apple pie. Nope, it ain't!

This "natural" process requires a bacteria (called rhizobia) in the soil. They form a symbiotic relationship with the clover plants. The bacteria get their food from the clover and the bugs use atmospheric N to provide the plant with available N. Guess what - the rhizobia, too, have been imported.

Searching for some natural holy grail you advance another angle. It must be the case, surely, that this symbiotic process of getting N from the atmosphere into the soil is natural, much more natural than building a urea N plant and putting on all that nasty urea.

Really? The major source of the nitrate N leaching into our groundwater is animal urine. The N in the urine comes from either ingesting pasture N, which comes from either clover N or fertiliser N. Clover N in urine behaves the same as fertiliser N in urine and hence clover N is not more benign than fertiliser N. Cutting back on fertiliser N will not solve the N leaching water quality problem.

One final roll of the dice. Our pastoral system is natural because the animals are outside all year round - right?

Think of our dairy cows; is it natural to be confined in a paddock all day and night except for the privilege of walking 1-2km a day morning and night to be milked?

Being outside, they urinate on the soil, giving rise to the N leaching problem. If the cows were housed indoors we could reduce this problem (by about 50 per cent). So if natural meant more "clean and green", having animals indoors would be more natural, right?

Using the word "natural" and its derivatives as a benchmark to assess our current and future farming system is nonsensical. It wrongly implies that if farmers do not adopt more natural systems, they will wreck the environment and the planet.

This PC-loaded environmental verbiage has the effect of undermining farmer's confidence at the very time when we need them to stand confidently to confront the challenges of the future, including water quality.

*Doug Edmeades is a soil scientist and managing director of agKnowledge. He was Federated Farmers Personality of the Year in 2012 and is a former Landcorp Agricultural Communicator of the Year.

Straight Furrow