My small plot (mainly meadow and orchard) is on the edge of a village with a footpath near by. Vehicle access is by a private gated track for a few fields (and owners) and is not a public right of way - unfortunately one of the metal track gates has been stolen and another damaged and Google Street View have had the cheek to travel along and film a section of it from the dead end of a public road to a by-pass (still at the early stages of getting them to remove the footage which shows their vehicle entering the gated track).
I get a couple of random dog walkers determined to walk through, one middle aged woman kicking a ball around for two dogs in a newly planted area of young trees seemed surprised someone 'owned' it and oblivious to the obviously planted trees!
Teenagers randomly appear from the cover of the hedgerows sometimes when I turn up and would seem to be smoking something other than just tobacco (the occasional purge in the nearest village causes them to stray away from the houses).
The track and public footpath alongside gets fly-tippers and people in random sexual liaisons and and the odd drug dealing exchanges - with various biological and packaging debris associated with the activities (the Police are taking more interest since the drugs wrappers went from a herbal to powdery residue).
Last year I cleared part of the grassland mowings with an old fashioned hand hay-rake (it took some time into the evening). The car that parked up at the other end of the field with its occupants divesting items of clothing weren't expecting someone with an oil-lantern and hay-rake to wander out of the twilight and they drove off rapidly crunching through the gears without getting dressed!
Despite this, I'm fortunate that the agricultural neighbours and nearest household neighbours are decent and communicative and keep an eye out for anything dodgy, as do the genuine regular local dog walkers and walkers. (I really sympathise with those who have 'problem' and misguided neighbours or persistent trespassers, thieves and vandals and poachers).
I'm easygoing with folk passing by who are genuinely interested, but firm with randoms whose approach is shifty or suspicious.