Picture posting is enabled for all :)
erm, if this is part of your tenancy agreement, and you ain't happy with it, why did you take an allotment there? A lot of sites have a 'no shed' rule, some have a 'no tree' rule as well. some sites have a 'no livestock' rule, others allow livestock, it's not unusual to have prohibitive rules or conditions of tenancy on allotments.
My intention is not to make waves, its simply a case of I believe that in life if somebody wishes to put restrictions upon us, then we have a right to know how they qualify their reasons for the restrictions..? I simply wish to get to the reason for them and then, if reasonable, abide - if not bring their reasons up at the next allotment holders meeting to see if 'we' as a group wish to challenge their rule...