Long-term tractor test: Zetor Forterra 9641 When there are cattle to be fed, yards bedded and muck shifted before the next milking, a tractor that ‘does exactly what it says on the tin’ is essential, and ‘mechanical’ and ‘conventional’ take spec priority over ‘electronic’ and ‘automatic’. Martin Rickatson details how our Zetor Forterra 9641 long-termer has fared in meeting yard/field requirements on our host Dorset dairy unit