This week sees two major farming conferences take place in Oxford. The Oxford Farming Conference was first held in 1936, while the Oxford Real Farming Conference is now in its eleventh year. Charlotte Smith talks to the organisers of both, and asks why TWO conferences are needed. We meet the tenant farming couple looking for a new home for their 200-strong herd of pedigree cattle. David and Sue Knight have spent the last 30 years building up their herd - but now face having to sell almost all of them, if they can't find a new tenancy by March. Farmers have long competed to see who could get their best harvest, but now they're combining forces to try and increase yields. What started as a yield competition has morphed into a network of around 300 farmers who are measuring and sharing every step of the process in the hope of increasing the amount they grow. We find out about YEN - or the Yield Enhancement Network - which brings together farmers, researchers and industry specialists. Presented by Charlotte Smith and produced by Emma Campbell.