This has been the wettest harvest I can remember. As the rain pours down on the south Cambridgeshire prairie, turning my wheatfields into porridge, there is one compensation. I have had time to read, mark and inwardly digest the musings of the Prince of Wales. And I find myself greatly puzzled.

Genetically modified crops - like other theological topics - leave me militantly agnostic. I am, however, happy that they are safe to eat since a zillion litigious Americans have been munching them for ages and nobody has yet sued Monsanto.

Quite what the effect of GM technology will have on the environment is, I readily admit, yet to be proved. Alas, if the Prince has his way we shall never know. The Organic Taleban have decreed that it is far too risky to conduct trials. This is based on their doctrine of the Precautionary Principle which, roughly translated, means that nobody must experiment with anything unless they are totally certain there is no risk.

Thank goodness the Organic Church had not been sanctified when Alexander Fleming was messing about with moulds. Penicillin would never have been invented because, like any scientist, he could not possibly have guaranteed that there were no risks.

So ferocious and puritanical is organic theology today that many believers are willing - even eager - to destroy any GM trial planted in Britain. Again, I fail to understand why it is acceptable for a member of the Organic Church to enter a farm and destroy a GM crop because the offending plants might - just might - pollute the surrounding flora, yet if I were to break into the library at Highgrove and burn the Prince of Wales's books because they might - just might - pollute the minds of innocent children, I would rightly be regarded as a lunatic and a vandal.

Seeds of discontent

Talk of burning reminds me that our grain dryer is working overtime. Thank goodness the price of oil has fallen because we've already used 4,000 litres of the stuff. Of course, an organic farmer would let the sun do the job. But he might have to wait until November, by which time all the grains would have sprouted.

The Prince of Wales is worried that small farmers throughout the world will somehow be forced - or simply seduced - into buying GM seeds from one of the hated multinationals. Having done so, these farmers will, he assures us, face inevitable ruin.

I am puzzled why small Third World farmers or, come to think of it, big barley barons like me, will somehow lose control of their own destiny and become helpless puppets of some vast corporation. Every farmer I have met is curious to try new varieties and new techniques. If these turn out to be successful, the farmer repeats or increases the experiment. If the crop is unsatisfactory, or the cost too great, the farmer simply reverts to traditional practices.

Yet, according to the Prince, this will not occur when GM crops are planted. From that moment on, the farmer appears to lose his independence, opinions and skills. Quite why remains unclear.

I am puzzled yet again when I listen today to the Organic Mullahs shouting from every minaret that these poor Third World farmers will not be able to plant the seeds that result from their GM crops because the greedy multinationals demand to be paid. The same applies today to any conventional variety. If I wish to plant this autumn seeds I harvested this summer, I can only do so if I pay a royalty to the breeder. Surely it's right to reward the plant breeder.

For 60 years hybrid varieties - usually maize - have been used from Kenya to Kansas. And it is impossible to plant seeds from a hybrid variety because they do not “breed true”. So every year the farmer must buy hybrid seeds. For some reason the Organic Taleban have never once objected to this.

But what puzzles me most about the Organic religion is a single fundamental fact. I grow wheat five times in a decade and usually produce 4 tonnes per acre. My organic friends grow wheat less than three times in a decade and are happy if they produce 2 tonnes per acre. Thus after ten years I will have harvested 20 tonnes while they may have harvested 6.

So there are only two ways that organic agriculture can feed the world. Either we must triple the area of land cultivated (destroying almost all of the rain forest) or the world's population must eat a vegetarian diet.

A plague on him

The Prince of Wales clearly feels deeply about the plight of Third World farmers. And he is right to do so. But I am puzzled as to what advice he would give them if their crop is attacked by a plague of locusts. Locusts appear only when there is a lot of green material to eat, which is why they never occur during droughts. The only organic way to kill one is to squash it with your heel. This can be tiring if several million are eating your crop of sorghum. But the sun has come out and I can hear the combine harvester warming up. Enough of this musing. There's work to be done.

Oliver Walston is a farmer in Cambridgeshire

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