Fifty years ago, I was a young geography teacher all excited by a new book that had just been published.

Rachel Carson had written a damning indictment of modern scientific agriculture, The Silent Spring, and its message is as true today as it was in 1962.

She was struck by the fact that there were far fewer song birds around than when she was a child, and that should resonate with many of us these days as recent springs seem to be even more silent than in the past. Where have all the sparrows gone?

She realised that powerful synthetic insecticides and pesticides were poisoning the food chain, from the lowest insects upwards, resulting in bird eggs with very thin shells, among other problems. She tells of Californian gulls poisoned by a pesticide used to control a harmless gnat, and the aerial spraying of DDT – to eliminate moths and ants – which killed blackbirds and larks.

Her message had a startling impact that ranged from the banning of the indiscriminate use of DDT to the formation of the Friends of the Earth and Greenpeace.

She showed that the blanket use of pesticides causes resistance to build up and this accumulation in the food change leads to birth problems and the death of young mammals and fish. The seas are increasingly changing their chemistry with the run-off from insecticides and nitrate fertiliser, resulting in seriously stressed marine life.

We really don’t think through what we are doing some of the time, and often we don’t seem to care. This must be the case with the use of neonicotinoid insecticides to coat grain seeds so that they don’t get eaten. It certainly protects them, but the unforeseen consequence is colony collapse disorder in honeybees and subsequent crop pollination difficulties.

Again, the increase in hordes of rabid feral dogs in India was not a predicted consequence of using diclofenac to treat cattle. It happened because 99.9 per cent of the vultures died of renal failure and so carcasses were not removed in the natural way.

Closer to home, we need a better reason than being tidy to use weed killers in our gardens and on our paths, and councils should give up spraying the pavements. It would be far safer – and cheaper – to use a hoe to chop out the weeds, or even to let them grow.

Similarly, genetically-modified crops might work, but it could be that we have yet to acknowledge the importance of not removing a link in the chain. Lacewings and hoverflies will safely sort out the aphids for us at a fraction of the cost of engineered aphid-resistant wheat seeds.