Water Stewardship Information Sources

Citation Baghuguna, D, Mitchell, SJ and Miquelajauregui, Y. 2010. Windthrow rectruitment of large woody debris in riparian stands. Forest Ecology and Management. 259:2048-2055.
Organization UBC
URL http://cef-cfr.ca/uploads/Membres/Windthrow.pdf
Abstract/Description or Keywords To document the impacts of windthrow in riparian leave strips and identify the components needed for
small stream large woody debris (LWD) recruitment modeling, we monitored nine small streams at a
temperate rainforest site in coastal British Columbia. This study was a component of a larger integrated
study of forest management impacts on small streams. A series of small clearcuts were harvested in 1998
in a 70-year-old second growth stand that had regenerated naturally following logging and wildfire. Three
cutblocks each were assigned to 10 m and 30 m buffer width treatments and three areas were assigned
as unharvested controls. Seven years after the 1998 logging, all logs greater than 10 cm diameter that
spanned at least part of stream channel width were measured. A total of 179 logs were recorded. Postharvest
windthrow was higher in the 10 m buffer treatment, while competition-related standing tree
mortality was higher in the controls. The major windthrow events had occurred in the first and second
years after logging of adjacent stands. There was no significant difference in the number of spanning
and in-stream logs in the 10 m, 30 m buffer and control treatments. More than 90% of the LWD was in
the 10–30 cm diameter classes. The majority of logs were oriented perpendicular to the stream channel.
At the time of measurement, the majority of these trees were still suspended above the stream channel,
indicating that the recruitment of logs into the stream channel is a long-term process. Time to recruitment
into the channel is dependent on log and valley geometry, log size, species, and log condition prior to
toppling. Log height above stream was negatively correlated with log decay class and valley width. Log
length was negatively correlated with state of decay, and many windthrown logs were in an advanced
state of decay before they entered the stream.
Information Type article
Regional Watershed Lower Fraser
Sub-watershed if known
Aquifer #
Comments
Project status complete
Contact Name Stephen Mitchell
Contact Email [email protected]