You say Wiltshire... I lived in Wiltshire for nearly 20 years; much of the ground there is very very claggy when wet. So don't rush in with any plans until you've seen it through a winter
(Just realised you'll know all about the ground, being a gardener!
)
If the local farmer is grazing it with cattle now, I'd keep on with that at first. Make sure you have a proper agreement in place so that s/he doesn't gain permanent rights
And, if the fence is cattle-proof now, make sure the fencing is the farmer's responsibility. Which may mean you get little money, of course, but you also get it kept grazed and the fence in good order
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