What is the correct choice when making Observations of a restoration site? The initial plants were planted by humans, but subsequent plants have reproduced on their own. Some original plants remain.
It seems to me that recording the fact that it is a restoration site would cover all these bases. That option is available in Calflora.
As you note, “restoration site” is not an available designation in iNaturalist. So as covered by numerous other threads here on the iNat forum, if you can tell that the plant is one of the originals placed by a human, it would be cultivated. If you can’t tell, or if it’s clear that the plant is from a subsequent generation that reproduced on its own (without obvious tending, watering, etc.), then it would be naturalized, and therefore “wild.”
If the individual plant you are observing was planted by humans, it should be marked as captive/cultivated.
If the individual plant you are observing was not planted by humans, it should be marked as wild, even if it was seeded from a captive/cultivated individual.
If you aren’t sure, take your best guess.
I’d mark as wild with a note in the description that it’s offspring from a restoration planting. As long as something is reproducing and surviving on its own without a human tending it, it counts as wild.
To echo what’s been said already, if it’s clearly one of the individuals planted (if it has some type of marking, as some often do), then mark as captive. If not, or if you’re unsure, I’d do wild.