Cordova - Battle against loosestrife
By Mark Hoult
Community Press Online
Posted April 25, 2005
Purple loosestrife was introduced to North American by
early settlers close to 200 years ago and spread quickly
across the continent. But it was only within the past
15 years that an effective method was found to stem the
spread of the attractive but deadly plant that has infested
wetlands and even agricultural land, to the detriment
of native vegetation, says Dawn Hutchinson, of the Ontario
Federation of Anglers and Hunters.
Hutchinson, who is part of the federation’s Invading Species
Awareness Program, spoke to more than 50 area woodlot
owners during the Annual Spring Workshop of the Upper
Trent Valley Chapter of the Ontario Woodlot Association
held April 16 at the Cordova Community Centre.
“We’ve been controlling purple loosestrife successfully
for more than ten years now,” Hutchinson said.
However, because purple loosestrife has been brought under
control doesn’t mean the threat has entirely vanished,
she said, stressing that the plant must still be managed.
Unfortunately, the plant and its threat to local habitats
have for the most part dropped from the radar of the Canadian
media, Hutchinson said.
Which makes educational initiatives such as the Invading
Species Awareness Program and Project Purple Week, all
the more important. Project Purple Week, to be held this
year August 1 to 7, is an educational initiative that
often involves enlisting the services of organizations
such as the Scouts and Guides, who are called on to co-ordinate
events and discussions, Hutchinson said, stressing the
need to keep an awareness of purple loosestrife “in the
Purple loosestrife can destroy native habitats because
it displaces the native plants that wildlife depend on
for their survival. It can even spread from wetland to
agricultural land, making it a problem for farmers. And
once it has a foothold it is very difficult to get rid
of by normal methods. Cutting and pulling the plant can
result in only limited success in small areas. And chemical
control is far from being an ideal answer to the loosestrife
infestation. But in the early 1990s researchers hit upon
a perfect biological method of controlling the spread
of the plant. They decided to introduce a natural enemy
in the form of two species of beetle which survive by
feeding on the leaves of the purple loosestrife. Following
extensive research, the beetles were introduced into Canada.
The beetles depend on purple loosestrife to complete their
life cycle, so there were no concerns about the insects
destroying native plants, Hutchinson explained. They feed
on the growing tips of the plant, reducing its ability
to flower and produce seed. Eventually infected plants
look as though they have been torched, she said.
The beetles have not entirely eliminated the plant which
it depends on to survive, so purple loosestrife remains
in the ecosystem, Hutchinson said. The difference is that
the beetles have created “a natural balance.” As the co-ordinator
of the invading species program she continues working
with local OFAH clubs, cottage associations, land owners
and naturalist groups to keep purple loosestrife under
Hutchinson noted that many land owners can’t afford the
$900 it cost to do a beetle release. However, the OFAH
will arrange for funding for land owners, especially if
they have a large wetland area. “We will work with you
and initiate a release if you commit to monitoring it
for three or four years,” she said.
Last year there were over 80 releases in eastern Ontario,
Hutchinson said. Usually a mixture of 5,000 larvae from
both species of beetle are released into an ecosystem,
she said, noting that the larvae are laid on the leaves
of the living plant.
The Invading Species Awareness Program monitors the spread
of invading species province wide, while trying to prevent
the introduction of new invading species, Hutchinson said.
Zebra mussels are another example of how quickly an invading
species can spread. They were introduced to the Great
Lakes by ocean-going vessels and then moved successfully
into the lake system and through the province. To keep
zebra mussels under control boaters are encouraged to
practice “simple boat hygiene.” This means washing boats
and any equipment that has been in the water.