I have been doing a bit of recent research into farming. Arable farmers are vulnerable to oil price fluctuations (OK, we know about red diesel), mostly in regard to fertilisers and pesticides. Oil prices also impact livestock farmers for transportation and feed costs.
It's getting to be more of a struggle, as the UK is now not capable of producing all it's own food. By necessity , we import. As farmers leave the industry , they are now typically selling land to developers for housing, meaning even less land to produce food for our increasing population. The boom years for famers have long gone, and you typically find some of the small farms, the farmers, or their spouses, have additional employment to make ends meet.