By John A. Wott, Director Emeritus One of the four primary forest trees of the Pacific Northwest is Thuja plicata, or the Western red cedar. There are “giants” of this species still growing after hundreds of years in protected sites in this state, but most were logged in great quantities as the lumber mills in the Pacific Northwest grew. The Washington Park Arboretum land, originally owned by the Pope Lumber company, was logged in the late 1880s and then basically clear cut of any remaining harvestable trees a few years later.