Tucker Miller is an agricultural advisor. For a few years now, he has observed ever-increasing numbers of so-called “superweeds” appearing in fields of GM crops. As time goes on, he is finding it more and more difficult to advise farmers on how to deal with them.

The weeds are no longer so easy to destroy and are now gaining the upper hand. Farmers are faced with significantly reduced yields and, at the same time, find themselves using increasing quantities of herbicide.

Roundup-resistant Palmer’s amaranth is just one of the weeds now spreading through US fields. This fast-growing plant can reach a height of 2.5 metres. It chokes out soya beans and cotton crops, and its stem is so tough it can damage harvesting equipment. Now, a losing battle is being fought on many US farms. Agricultural advisors see no solution other suggesting that farmers try different – and ever stronger – poisons. Some of the superweeds have absorbed genetic material from GM plants into their own genetic makeup, allowing them to grow faster and stronger than their predecessors, which could still be killed with glyphosate.

“If the weeds get sun and water, they can grow five centimetres in a single night. The next night, their grow another five, and already they’re ten centimetres tall – and uncontrollable. As soon as they reach ten to twelve centimetres, herbicides can no longer keep them in check. So you only have two days to spray them and, if it’s wet, you have to do that from an aeroplane”.