Plant species diversity and soil quality in harvested and grazed boreal aspen stands of northeastern British Columbia

  • Published source details Krzic M., Newman R. & Broersma K. (2003) Plant species diversity and soil quality in harvested and grazed boreal aspen stands of northeastern British Columbia. Forest Ecology and Management, 182, 315-325.


This study is summarised as evidence for the following.

Action Category

Log/remove trees within forests: effects on understory plants

Action Link
Forest Conservation
  1. Log/remove trees within forests: effects on understory plants

    A replicated, controlled study in 1988-2001 in temperate coniferous forest in British Columbia, Canada (Krzic, Newman & Broersma 2003) found that harvesting had a mixed effect on understory plant cover, but did not affect species richness or diversity. The cover of the most common herbaceous species bluejoint reedgrass Calamagrostis canadensis (harvested: 27.7%-38.9%; unharvested: 9.7%-17.9%) as well as of four more herbaceous species (harvested: 1.3%-5.9%; unharvested: 0.5%-3.7%) was higher in harvested than unharvested plots. In contrast, the cover of Mountain Sweet Cicely Osmorhiza berteroi (harvested: 0.0%; unharvested: 0.2%-0.7%) was higher in unharvested plots. Cover of regenerating trees was higher in harvested plots: trembling aspen Populus tremuloides (harvested: 54.9%-63.9%; unharvested: 3.5%-4.1%) and balsam poplar Populus balsamifera (harvested: 8.6%-12.5%; unharvested: 0.0%-0.1%) However, the cover of the shrub birch-leaved spirea Spiraea betulifolia was higher in unharvested plots (harvested: 0.7%-1.0%; unharvested: 7.7%). Numbers of species/5 m2 (harvested: 38-41; unharvested: 34-39) and plant diversity (Shannon's index harvested: 2.53-2.74; unharvested: 2.78-2.89) were similar between treatments. Data were collected in 2001 in three replicates of two harvested (in 1988-1989) and two unharvested mature aspen plots (5 ha). Species richness and diversity were calculated for 40 subplots of 0.125 m2 in each plot (total of 5 m2).


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