森 and 林: places where trees grow together
Read two words for wooded places without inventing a rigid classification.
A forest space
森 (もり) means forest. 「森の中を歩きました」 means walking through the forest.
「森の入口で待ちました」 says the speaker waited at the forest entrance. It does not establish entry into the forest.
A stand of trees
林 (はやし) also refers to a place with trees growing together. 「松の林が見えます」 says a pine grove is visible.
「林を抜けると、川があります」 says there is a river after passing through the woods. 抜ける links passage to the location beyond.
Avoiding fixed classifications
Everyday uses of 森 and 林 overlap. Do not insist that one must be natural and the other planted.
「この林は森の一部です」 can describe a stand of trees as part of a larger forest. Read the scope and naming in context.
Can 森 and 林 always be classified as natural versus planted?
Show the answer and why
No. Everyday usage cannot be fixed by that criterion alone.