Biodiversity needs agricultural inputs

Reducing the requirements of biodiversity into simple farm guidelines can be difficult.  Someone with experience can suggest the most effective measures taking into account the specific location and landscape features of the farm. However, the underlying requirements are fairly simple. A wide range of biodiversity should be provided with food and shelter throughout the year.

The most powerful weapons are to encourage flowers for as long as possible over the summer and to feed birds during the winter. Flowers support insects which in turn can be bird food over the summer months.

The earliest flowers in the spring are in hedges and hedgerows and some over-wintering arable weeds, if uncontrolled, can flower very early in the year. It is then the turn of summer and autumn flowering species, which traditionally were flowers in grassland and arable weeds. These have disappeared from arable areas and need to be replaced with sown mixes.

Perhaps the best approach is to sow a flower rich grass mix which can be either based upon wildflowers or legumes developed for agricultural purposes (clovers, vetches and sainfoin). These need not be too expensive (seed £200/ha) and the wildflowers will last for many years and legume mixes several years if properly managed.

Weedy stubbles used to be a source of bird food during the winter. These can be replaced with sown grain and oilseeds, such as triticale, millet, quinoa, kale and fodder radish. It is best to go for the highest yield possible but support scheme payments only allow inputs that aid establishment rather than yield.

The need to comply with the conditions of support payments means that the objectives of flower rich grassland and winter bird seed are harder to achieve. The use of a fop or dim herbicide may help the flowering species survive in greater numbers and for more years in the grass mix and a shot of nitrogen would do wonders for seed production for birds during the winter.  

Jim Orson is a Specialist Adviser in NIAB TAG. He has a wide range of knowledge on crop production issues, particularly weed control and production systems. Jim has been keeping a watchful eye on the changing pesticide registration system in Europe and the new Sustainable Use Directive, which may influence crop protection and cropping systems through both reducing the number of available pesticides and how they are used.