1 of 13 Flora and Fauna: 1 | 2 | 3 | 4 | 5 Letters and Records: 1 | 2 Maps: 1 | 2 | 3 Native Americans: 1 | 2 | 3 AMERICAN PHILOSOPHICAL SOCIETY VINE MAPLE LEAF Meriwether Lewis observed this tree leaf, later identified as a vine maple, in the Columbia River area. "The leaf is petiolate, plane, scattered, palmate lobate, divided by four deep sinuses," Lewis wrote on Feb. 10, 1806.

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