How do you protect the land but allow tree collecting/farming?

How do you add people to protection when they buy lots?

How do you remove people?

How do you set protection for houses but not for mining near bedrock?

Very carefully.

Ask an admin, I'm sure they can do all of that.

Mods protect land. If you are the owner of the protected land, you can add members to your land.

/region addmember region name player name

/region removemember region name player name

When a Mod makes a protection for you, you can request that it goes 10 blocks deep and 25 blocks high (example). Or you can request it goes all the way to bedrock and as high as sky limit.

There is more information on the Minetown Wiki.

thank you