Conservation headlands are an area between the crop edge and the first tramline that are treated less intensively so that a greater range of broad leaved weeds and beneficial insects survive. They are usually the width of a part of the sprayer boom (4 - 6 metres) that can be swiched off to prevent the application of some pesticides. Conservation headlands were pioneered by the Game Conservancy Trust and are now commonly seen as farmers seek to encourage biodiversity in their fields.

A well established conservation headland sited adjacent to a grassy bank like this provides an excellent habitat for insects and the birds that feed on them. Conservation headlands vary in degree depending on how they are managed.

Most conservation headlands are not treated with broadleaved herbicides or pesticides. However this can still leave beneficial weeds with a very competitive crop against which they struggle. In this illustration the thinner area of the crop on the left has been sown at half the conventional rate. This provides better light penetration and creates a more successful conservation headland.

A good bank of beneficial weeds can take a long time to build up and one alternative is to purchase a seed mix to speed up establishment. This seed mix will be spun into a wheat crop in late autumn and then rolled.

A conservation headland in a wheat crop in June. The reduced plant population of the crop is allowing the beneficial weeds to flourish and flowering will not be far away. Note the cut margin adjoining the crop (a path) and the uncut area beyond that provide diversity of habitat.

By June broadleaved weeds in the conservation headland will be in flower. Apart from poppies, corn cockle, corn marigold, corn flower and corn chamomile may be found.

The rich floral diversity of this conservation headland is providing an excellent nectar source for insects which in turn provide food for birds.

A conservation headland in a crop of spring barley in August. Note how the wildfowers hardly extend into the area of the crop that has received a broadleaved spray.

The rich biodiversity of the conservation headland also carries contamination risks for the grain sample. Impurities can lead to rejection of the crop and significant loss of price which can be ill afforded in today's economic climate. One solution is for the farmer to cut the conservation headland after he has cut the rest of the crop and to treat the grain as a feedstuff for stock or game - a process which returns beneficial weed seed back to the farm.

Conservation headlands provide an ongoing source of food for insects and other species in the food chain well after the summer period as this flowering headland in October illustrates. If conservation headlands are cut high by the combine harvester, most of the broadleaved weeds will continue to flower and set seed in September or later.

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