A typical foliage leaf of a plant belonging to the dicotyledons is composed of two principal parts: blade and petiole.

双子叶植物典型的营养叶由两个主要部分组成：叶片和叶柄。

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When in leaf it's easier to spot because it seems as if the foliage has been damaged by a severe frost and turns limp and black.

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Invisible and, often odorless, green leaf volatiles emitted from vegetation act as a defense mechanism, communicating to other foliage that danger is near.

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