Do tree stumps do anything if you don't cut them down?
After some testing, it does appear that non-fruit bearing trees do NOT re-grow from stumps.
This information is taken from the updated Wiki page:
Non-Fruiting trees take 10 to 12 days to grow from being planted, as long as the tiles in a two tile radius remain clear. They will grow at a reduced rate if other objects occupy part of this area and will not grow beyond a sapling if there is another tree directly adjacent. Once fully grown, the surrounding area can be paved with no ill effects on the tree, although doing so will prevent seeds from being dropped. These trees do not regrow from a stump, a new seed must always be planted.
Perhaps there is something wrong with the game version or savefile I'm using, but according to my tests, stumps have two notable properties for me:
- They continue to drop seeds/cones/acorns like full-size trees.
- They do not grow back into trees. I've backed up my savefile and essentially slept through two seasons (while clearing seeds and debris around the stumps) to verify this. I tried varying the spacing between stumps and the tree type with no effect.
This is with Stardew Valley from GoG, v1.05. I don't know if it makes any difference, but I cut the trees down with an iridium axe. (Maybe the iridium is radioactive and kills trees while simultaneously making them sprout seeds from the stumps?)
They don't do anything except taking space and growing back to a tree after 10 days.
Normally, new trees take a long time to spawn (small tree appears, then grows to a big tree) if you chop them down completely. Therefore if you are planning to farm wood, leave the stumps; if not then chop the stump too.