Respawn System

Nearly everything respawns, but on different timers.

Trees regrow from stumps quickly Stumped trees regrow after a week.
If you hover over the tag item left behing it will show a timer - most times

Copper, silver, stones, structures, mostly anything destroyable will respawn after 7 days (IRL).

Pickables, such as carrot seeds, barley, etc. if they do not have a vanilla respawn time, they will respawn in 24 hours. These pickables are also protected against destruction, such as berry bushes, and can only be removed from inside your own ward.

Prevent Respawn

Objects

To prevent respawn of a destroyed object put up a ward or a workbench.
This blocks it in its vanila radius - the visiual ring in the game
Nothing else will block it
e.g. to stop large rocks, copper nodes, destroyed trees(stump removed), buildings etc.

Monsters

The Vanilla items that suppress respawning are unchanged e.g. Torches, campfires, workbenches etc

Doesn't Respawn

Dirt, raised or lowered (dug out) does not respawn in most cases.