Vegetation relationships among some seral ecosystems in southwestern British Columbia.
A new classification scheme is proposed for managed second-growth forests, based upon ecologically equivalent sites rather than on purely floristic or structural characteristics of vegetation. For demonstration purposes, 6 structural (developmental) stages were sampled and classified. The seral stages, listed in increasing age after harvesting are as follows: initial, regeneration and early immature (all at sites which had been clear felled, burned, and planted with Douglas fir), late immature, mature, and old growth (sites established after logging or wildfire >50-300 yr ago). The results of numerical and tabular analyses suggested the presence of 2 major floristic groups (seral associations) of the above seral stages: (i) Epilobium/Polytrichum (initial and regeneration seral stages) and (ii) Pseudotsuga/Hylocomium (early immature to old growth seral stages). The Epilobium/Polytrichum seral association was found to represent seral vegetation of regeneration stages on 4 different site types, all of which are common in southwestern British Columbia.