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An illustrated flora of the northern United States Canada and the British possessionsfrom Newfoundland to the parallel of the southern boundary of Virginia and from the Atlantic Ocean westward to the 102d meridianBookby Britton, Nathaniel Lord, 1859-1934
Published 1913 -
Field guide to Washington's rare plantsGovernment Document Bookby Rush, Tracy
Published 1999 -
Pacific Northwest Region invasive plant programpreventing and managing invasive plants record of decisionBookPublished 2005