STAND DYNAMICS AND CONSERVATION OF AN OLD-GROWTH ENGELMANN SPRUCE-SUB-ALPINE FIR FOREST IN COLORADO

Old-growth studies normally emphasize structural characteristics, but it is also critical to understand the underlying processes that shape old-growth forests. In Colorado, the issue of old-growth forest manage ment recently came to a head in Bowen Gulch, one of the last extensive , high-quality, old-growth spruce-fir forests in the Front Range. The area was originally slated for logging, but public pressure led to its protection. We examined the physiognomy and stand dynamics of Bowen G ulch and report the results of that study here. Structurally, Bowen Gu lch is an exceptional old-growth forest with high densities of large, old trees, snags, and logs and complex vertical stratification. Howeve r, age data and tree-ring chronologies reveal that much of the forest is probably in a transitional phase of development. Studies of forest dynamics have demonstrated the importance of fire, spruce beetle outbr eaks, and windthrow in the subalpine zone, which brings into question the feasibility of old-growth preservation. Unfortunately, policies th at balance preservation with the inevitability of disturbance have bee n lacking. The rarity of some old-growth types necessitates that natur al areas be dedicated to old growth, but prudence and forest dynamics also dictate that we should plan for renewal of old growth on a landsc ape basis.