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piled trees within a day of our conversation. We
have since collaborated on making a local man-
agement plan for forest pests, and we are working
with young adults from the community to translate
new cultivars and varieties of trees into Cree.
The Wind Hit Hard
In the spring of 2022, a forest mulcher had arrived
in a Manitoban community to remove trees from a
small municipal plot to make room for a new garbage
disposal site. Using a compass, the contractor, created
a square cutblock, approximately 1 hectare (2.5 acres)
in size. The region, an area within the former glacial
Lake Agassiz, had shallow soils above a pure sand
base. After felling the trees, the contractor spread
about half a meter (~1.5 feet) of gravel atop the cut
block, but no one wind-firmed the tree stand, leaving
the trees particularly vulnerable to windthrow.
Within a day, the community Facebook group
was filled with posts questioning the purpose of
having cleared such a large area and how it would
be an eyesore. Four days after the first tree was
felled, a moderate wind blew in from the north.
For three hours, tree after tree fell to the wind.
The local police closed the sidewalk and a lane of
the highway to travel. Nearly 460 trees were lost
during the first blowdown, including half of the
100-meter (328-feet) buffer, exposing the site to
the highway. The area now appeared tree-barren.
The community erupted on Facebook. Those who
had already questioned the purpose of the cut-
block now expressed their outrage about so many
trees blowing down. The situation became so
contentious that it was a talking point in the local
municipal election over the coming months. The
additional loss of trees through the summer and fall
storms intensified the debates on social media.
For practicing arborists and urban foresters, this
urban cutblock offers two important lessons. First,
the square edges of the cutblock without consider-
ation of stand and individual tree factors increased
the vulnerability of the trees to windthrow; the cut-
block should have had an irregular shape, feathered
edges, and a stand-specific prescription (Niddrie, >>
Windthrow on a 1-hectare (2.5-acre) cutblock following a moderate windstorm. The recently cleared area left the
remaining trees exposed to unfamiliar wind forces, resulting in extensive tree failure. Photo by Alex Martin
