Building intensive dairy farming operations indoors in the Mackenzie Basin would be “like building a city for 270,000 people… and having them crap on the ground,” said the eloquent co-leader of the Greens, Dr Russel Norman.

But on the party’s own website, former Green party co-leader Jeanette Fitzsimons is extolling the virtues of herd homes – sheds erected to house dairy cows and keep them from damaging pasture during wet winters, and reducing nitrous oxide emissions.