If you visit Jersey you can guarantee to see two different crops in the fields. Definitely lots of potatoes from early January right through to late summer. Sometimes sweet corn . Hay crops will be grown for fodder. The lack of variety is an issue. Potatoes grown year on year in the same fields has led to overuse of chemicals. This in turn leaches into our reservoirs, causing contamination. Recently we even stopped using the water from our largest reservoir because of this chemical issue . The reservoir is now back in use but the problem hasn't been solved.

In the UK crop rotation is the norm. I love coming to the mainland in spring to see all the yellow rape fields. Very pretty but also doing an important job in helping to add nutrients back into the fields.
Several years ago Jersey seemed to be experimenting with rapeseed. We had our own gorgeous fields of yellow. Since then clearly the experiment was shelved. Perhaps they felt more chemicals was the way to go!
Nature has its own way of reminding us about good practise in agriculture. This year along the edges of fields masses of rapeseed has sprung up. Is it there to tell farmers to get their act together. I hope so. From a photographers point of view its making some stunning photos. Hope you like them! 
How do you feel about this issue? Do you have similar problems where you live?