Change a terrain feature after some period of time?

i would like to make trees re-harvestable year after year…
(maybe subsequently implementing planting new trees, having trees growing to full size and later trees growing old and stop producing fruits)

but… in order to do so i’d have to make the trees change from harvestable to harvested when applicable, then become harvestable again in the next season (with seasonal harvesting periods this means that the tree will be unavailable to harvest until a year has passed)

now, i remember that crops did grow over time to become harvestable, so if i could look at the relevant code i might understand how to make what i want.

thing is, i’m new to cata code, and i cannot find the relevant code as of yet, even though i did some grep checks and checked the github for the farming PR (could not find the latter).
only (slightly) relevant thing i found is the brewmaking PR, but it doesn’t entail changing of terrain features.

specifically i looked at iexamine, but in there are only the planting functions, not the growing ones.
if anyone could point me to the right direction, i’d appreciate it.

IIRC the function for plants is examine::aggie_plant().

found it. ty. (i should have found it from the json reference of plants i guess)

still brushing up on my c++ knowledge (i only know python reasonably well) so more questions (similarly stupid) may be forthcoming.