Salem

So i am out in the middle of nowhere on bumpy ground and and a tiny tiny claim. I would rather have my claim be just my house for now.. once I get the ground flat enough. Fields look pretty big so I'd rather not have to claim fields I make until I have enough humors to kill crickets for claim upkeep silver. So if you make a field on unclaimed land how long does it take for it to decay? I'm hoping I can make fields and farm them and over time expand my claim to cover them.
(also if I make a second claim as a farm area do I have to walk back and forth between claims or is there a teleport option to travel between homestead claim and normal not homestead claims?)

Decay on buildings and objects is completely random, but unless something has changed tilled fields won't get hit by decay.