Conservation comment: We reap what we sow

I spent last summer living next to a giant paddock of maize. It was planted at this time of year in November, and harvested on April Fools' Day.

The current owner leases the farm to a neighbour, who leases the maize paddock, around 6ha, to a subcontractor.

Before being planted in Pioneer corn (soaked in neonicotinoid insecticide), the paddock was sprayed with Roundup.

Pioneer corn is produced by DuPont and Roundup is a product of Monsanto, the world's two largest seed companies and biggest rivals.

Together these two seed/chemical companies, along with the Swiss-owned Syngenta, own 47 per cent of the world's proprietary seed market.

Like little green clones, the maize grew at an alarming pace, unimpeded and unmarred by weeds, bees or any other insects.

As the corn stalks grew, harriers circled the crop looking for rats and mice which had begun inhabiting the paddock.

It was a second subcontractor who came to harvest the crop, which by April was a vast field of tall dead drooping maize.

He arrived in a growl of diesel-powered machinery, seven rigs in all, including a long-nosed tractor, harvester, three trucks and a fourth with a tank of diesel behind.

Within four hours the maize was cut and shucked, the kernels jettisoned into waiting trucks and on their way to be dried in kilns in Foxton, 90km down the road. Kernels quickly become mouldy if left in their raw state and need to be dried within three days. Everything else was left in the paddock.

The day after the harvest, a strong nor-wester blew through, lifting the corn debris into the air like a flock of crazy headless, bodiless brown crows.

Soon more flocks of introduced finches and sparrows were picking and chattering through the leftovers.

And the final outcome of all this high technological industrial agriculture?

After drying, the maize will feed battery-farmed chickens.

The rural land just north of Wanganui with its top flats and steep gullies holds Westmere silt loam, some of the finest growing soil in New Zealand.

The temperate climate and location, in the large Taranaki bite below Mt Taranaki, means abundant rainfall, albeit more predictable as weather patterns change.

Compared to much of the world, Wanganui is a food-growing paradise.

Why, then, are we using our very best food growing land to grow inedible, chemical-laden maize kernels to feed creatures that spend their lives in appalling captivity?

How much carbon dioxide ends up in the atmosphere along the way? Are DuPont's ubiquitous Pioneer Corn crops implicated in the disappearance of our bees? Is Monsanto's Roundup, as announced this year by French scientists, a carcinogen?

We reap what we sow. Who reaps the benefits of this type of agriculture? Not the chickens. Not the soil. Monsanto and DuPont together made sales of US$50 billion ($76 billion) in 2013.

Who's the April Fool?