I got some sorta-data and I'm not convinced damage or tool level plays a role in seed drops. PlantEverything seems to be making it so that you can get upwards of 4 seeds back for each beech tree. The mod makes it so that you get a max of 2 seeds per tree, but the tree looks at the loot table twice and it can double-dip in the seed drop and give you 4. I'm not sure if that's how vanilla does it, but it seems to give you the same upward trend vanilla does.

'Must have been getting some weird RNG because seed yield has been trending upward whether I use a bronze axe, a flint axe, or other trees to harvest trees.

Originally posted by Nesano:

I got some sorta-data and I'm not convinced damage or tool level plays a role in seed drops.
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Must have been getting some weird RNG because seed yield has been trending upward whether I use a bronze axe, a flint axe, or other trees to harvest trees.

This has been my experience, as well, but it's good to see some confirmation.

RNG takes a lot of samples to get a good feel for, especially when the randomness is complex. That is, you're looking at the output and trying to determine the chance to drop any seeds vs the chance to drop multiple seeds, and this is all complicated by having multiple chances to drop seed(s).

It appears to me that it was the PlantEverything mod that was actually skewing the drop rate.

To answer your question, I do not believe that "damage dealt" has anything to do with "items dropped", either in number or in contents. It's also entirely possible that one of your other mods is adjusting either or both of those, even if PlantEverything is removed.

I would suggest removing all mods entirely, if learning about base game mechanics is the goal.

All of that being said, I eagerly await the results of your testing; please keep us posted.