Forest Investment Account

Abstract of FII Project R02-40

" ALT="See below to download" WIDTH="100" HEIGHT="129" BORDER="0" bordercolor="#000000">

Plant species diversity and soil quality changes in harvested and grazed aspen stands

Author(s): Page, Hillary
Imprint: B.C. : Canada. Agriculture and Agri-Food, 2003
Subject: Cattle, British Columbia, Populus Tremuloides, Biological Diversity, Soil Degradation
Series: Forest Investment Account (FIA) - Forest Science Program


Land-use conflicts arise in aspen (Populus tremuloides Michx.) stands of the Peace River area, because these areas are important for both timber and forage production. Disagreements regarding cattle grazing on cutblocks concern the possibility of increased tree damage (browsing and trampling), decreased plant species diversity and reduction of soil quality, particularly increased compaction. The objective of our study was to determine the effects of harvesting and long-term cattle grazing on aspen cutblocks. This study focused on plant species diversity, soil quality, stem density and forage production in the Peace River region of British Columbia (BC). Research was carried out on a long-term study-site established 5 km south of Dawson Creek, BC. Sample collection and vegetation assessments occurred during the summer of 2001 and 2002. All data were analyzed as split-plot randomized complete block design, with three replications and four transects per plot. Summer and winter logging significantly increased aspen and total stem density relative to unlogged blocks, whereas ten years of cattle grazing had no significant impact on stem density. Increases in stem density did not significantly affect forage production, although the combination of ungrazed, winter-logged blocks resulted in significantly higher production values than did any other treatment combination. Logging effects on plant diversity could not be assessed due to temporal variation (i.e. data was collected at different times). Ten years of summer grazing, within summer-logged blocks, resulted in the increase of several forb and shrub species and a general increase in species richness in grazed blocks. Grazing resulted in the decline of two forb and two shrub species, an indication that these species were preferred by cattle in these blocks. Aspen density and plant species diversity was not adversely affected by grazing and forage production was not affected by logging activities, indicating there is no land-use conflict on these blocks.
Hillary Page...[et al.]

PDF Document

Download R02-40.pdf (1.2 Mb)

[Get Adobe Acrobat Reader] To view this document you need Adobe Acrobat Reader,
available free from the Adobe Web Site.

Updated August 02, 2006 

Search for other  FIA reports or other Ministry of Forests publications.

Please direct questions or comments regarding publications to