SmallF21, it's just a terrain update thing. If a player sees an active enemy farm, moves away (sending the farm into the fog), and returns later after the farm completely expires, there's no farm object left to update the current state of that terrain to the player, so it remains as-is with the previous appearance. The reason it's like this is to avoid a player seeing farms appearing/disappearing in the fog. Clicking that land would not highlight as an actual farm, so it's just a visual quirk. To fix this would require storing a lot of additional state information, so it was left unchanged.