How chemicals altered balance between farming and natural world

One overwhelming cause is behind the dramatic decline of so much of British flora: intensive farming.

One overwhelming cause is behind the dramatic decline of so much of British flora: intensive farming.

Britain is such a small country that it cannot afford separate areas for wildlife and agriculture, as to some extent is possible in the United States; here, farming and wildlife have to coexist side by side.

They coexisted successfully, if now and then uneasily, for thousands of years. Farmers might sometimes be annoyed at the "weeds" in their cornfields, but could never quite eradicate all the poppies, cornflowers and corn marigolds - so the summer fields were vibrant with scarlet, blue and yellow flashes in amongst the corn.

However, the chemical-based agriculture that started to emerge 40 to 50 years ago dramatically altered the balance between farming and the natural world. Potent herbicides allowed farmers to get rid of many of the unwanted plants in their arable fields, and their populations tumbled; sights such as a field of poppies, familiar to most people in Britain over the age of 50, simply disappeared.

It was not just in the arable fields, either, that wild flowers started vanishing: the grassland pastures where sheep and cattle fed also held rich communities of plant life, and they too have been badly affected. Here, the cause was not pesticides, but fertilisers. The proposition that adding fertiliser to a field causes flowers to disappear may seem counter-intuitive to non-botanists, but it is sadly true. What happens is that for a few species - and usually only the target grass -there is enormous benefit and vigorous extra growth, but this is so strong that it out-competes everything else. Other plants cannot survive.

Agricultural chemicals have been the main problem, but not the only one. Man has made many direct assaults on the landscape: sensitive habitats with specialised flora such as chalk grassland or lowland heath have gone under the plough or under concrete. The change in farming practices has also contributed, such as the shift from haymaking to silage and the destruction of hedges.

The fields still look green when you go for your country walk; but often, green is all they look, and the wonderful pattern of colour they once exhibited is no longer to be seen.