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undergrowth; weeds beneath a tree
森の下草を刈って見通しを良くした。
We cleared the undergrowth in the forest to improve visibility.
下草が生い茂って小道が見えなくなった。
The undergrowth grew thick and the path became invisible.
下草の手入れは山火事の予防にもなる。
Maintaining the undergrowth also helps prevent forest fires.