Included here is the Olympic Peninsula in the US state of Washington. It is bounded by Puget Sound and the Hood Canal to the east, the Pacific Ocean to the west and the Strait of Juan de Fuca to the north. The central area is dominated by the Olympic mountain range.
Of the endemic vascular plants so far recorded there are 10 species and varieties in 9 genera and 7 families but no endemic genera.
Buckingham, N. 1996. Flora of the Olympic Peninsula. Pacific Northwest Naturalist.
Reagon, A. B. 1934. The flora of the Olympic Peninsula, Washington. Iowa Academy of Science.