I have tested this one multiple times. This could be considered a more serious bug because the user cannot replenish health after a certain radius of area has been farmed.
Farmable objects only yield once. Meaning if you go to a parent object that produces a child object and you farm that child object once, when the child object is regenerated you no longer benefit from farming it the second time. This has to be a bug.
Here is a concrete example
You go get a pale berry from a pale berry tree for the very first time. You now have one pale berry in your inventory. You wait for the pale berry tree to reproduce it's berry. You go collect the pale berry again from the SAME pale berry tree and you will STILL have one pale berry in your inventory even though it is clear that you just farmed it a second time. The bug here being that these objects are somehow maintaining state of when you farmed them.