Bull Run RNA

Bull Run Research Natural Area (RNA) was established to represent ecosystems found in Western Hemlock and Pacific Silver Fir zones. The RNA has generally steep slopes and is heavily timbered. Streams located in middle and lower sections have steep-walled canyons in several locations. Compacted glacial till and cirques suggest that glaciation once occurred here. Forest stands are a mixture of noble fir (Abies procera), Pacific silver fir (Abies amabilis), western hemlock (Tsuga heterophylla) and Douglas- fir (Pseudotsuga menziesii). The vanilla leaf understory plant community predominates in Jackpot soil while the huckleberry understory plant community predominates in Last Chance soil. The protected Bull Run watershed is the primary drinking water supply for the City of Portland showing little evidence of human influence.