Since this is UK Agriculture I would suggest that you contact a solicitor on this. It would take a simple phone call to obtain your answer. I have included a couple of UK Farming solicitors that may be of service. You may call or email your inquiry to them in regards to this.
http://www.pearslaw.co.uk/agriculture.html
http://www.randlethomas.co.uk/html/qa_farming.html
Due to the variety of possible answers to this specific question then I would most certainly consult either with others that have come across the same situation as yours and talk with them or contact the solicitors above.
I am sorry but I am finding no UK laws that would pertain to your situation.
If I may further assist or help then please reply. You may either accept or not accept this answer as you are under no obligation to do so. Sorry that I can not be any more specific to your question.
I will be glad to further assist if needed.
Please click the
Green ACCEPT if my answer is helpful. Positive
FEEDBACK and Bonus is appreciated.