Pesticides
Two main types
of pesticides are used in forest protection and management: insecticides for
insect control, and herbicides for control of competing vegetation in reforested
stands.
Historically,
conventional chemical insecticides have been widely used in parts of Canada to
control forest insect pests. In Alberta, however, these insecticides have not
been used on a major scale in forested areas. Currently, Alberta uses two types
of biological insecticides to control forest insect pests: biological-based
products; and biochemical-based products, such as insect growth hormones and
phermones.
Herbicides are
one silvicultural tool that may be used to manage forest vegetation to achieve
specific forest management goals. These products have proven to be an effective,
cost-efficient means of managing vegetative competition in reforested coniferous
cutblocks. The large-scale application of herbicides is a relatively new
practice in Alberta forests.
In Alberta, the
provincial government supports the responsible use of herbicides for forest
vegetation management in accordance with provincial and federal legislation and
provincial guidelines. According to Alberta's guidelines, herbicides can be used
to reduce competition from non-crop vegetation (grass, shrubs, etc.) during site
preparation and stand-tending operations. The objective is to establish and
maintain or improve the growth of desired tree species.
All forest
vegetation management practices, including herbicide use, are determined both by
forest management objectives (such as wildlife, recreation, watershed, grazing)
and by the vegetation management options available to meet those objectives in
an environmentally sound manner.
Department of the Environment. State of the Environment Report, Terrestrial Ecosystems. Edmonton: n.p., 2001. With permission from Alberta Environment.
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