Sister Rocks

Sister Rocks Research Natural Area (RNA) was established to represent forests dominated by pacific silver fir (Abies amabilis). The topography of the area is gentle to moderate, except along the lower margins where there are steeper slopes. Pacific silver fir (Abies amabilis)/Alaska huckleberry (Vaccinium alaskaense) and Pacific silver fir/rosy twistedstalk (Streptopus roseus) are the dominant plant communities. Pacific silver fir dominates the entire tract with western hemlock (Tsuga heterophylla) as the common associate.  Douglas-fir (Pseudotsuga menziesii), noble fir (Abies procera), mountain hemlock (Tsuga mertensiana) and lodgepole pine (Pinus contorta) are also common tree species.