The John Prince Research Forest is located northwest of Ft St James in central British Columbia at the northern limit of the range of interior Douglas-fir (55o latitude). Mean annual temperature at this Sub-boreal Spruce site is lower than at any of our other locations and precipitation is moderate. The approximately 130-year old forest was comprised of about 85% Douglas-fir, with six minor species including spruce, paper birch and trembling aspen. Site index of Douglas-fir was higher than at many other interior locations and stand basal area and volume were surpassed only by Narrows Creek and the coastal site (Malcolm Knapp). Subalpine fir, shrubs, herbs and mosses were present in varying amounts in the understory. Soils were Luvisolic gravelly clay loams to loams and the forest floor was thicker than at the other interior locations.