The L.R.C.A. is keeping an inventory of all confirmed Purple loosestrife sightings. This will help to monitor the spread of loosestrife. When staff time permits, hand-pulling is undertaken at selected sites.

Volunteers have been a big help at our annual Losestrife Control Days. They worked hard to dig out loosestrife plants along Neebing Ave. in the south end of Thunder Bay. Lakehead Conservation is grateful for their efforts.

The Conservation Authority also raises public awareness through media reports, brochures and displays.

Purple loosestrife has rings of purple flowers at the top of long stems. The stems often branch.

In 1997, Lakehead Conservation released Galerucella beetles at two of the region's worst loosestrife sites. One site was on Montreal St. across from Bombardier and the other was on Highway 17 at Birch Beach Road.

The beetles quickly crawled and flew their way to nearby loosestrife plants. When the sites were inspected in the fall, small holes could be seen in the leaves of loosestrife plants immediately around the release site and also on plants across the road. Some flower tops looked dried out and chewed up.

These insects feed exclusively on purple loosestrife. They will be an effective weapon against loosestrife because they eat the leaves, thereby slowing growth, and damage the flowers resulting in less seed production. Less seeds is an important step in controlling loosestrife, since each flower stalk can produce 100,000 seeds!

In July, 1999, staff re-visited the two release sites to assess the Galerucella beetle populations. The sites were inspected for the presence and amount of adult beetles, eggs, larva and, loosestrife plants, as well as the beetles dispersal range. Other signs of the beetles include numerous small holes in loosestrife leaves and withering of the growing tip.

Beetles at the Birch Beach site are doing especially well. Conservation staff observed egg masses on the leaves and both adults and larvae had been busy chewing holes in the leaves. The most significant damage was made by larvae feeding on the growing tip and preventing the loosestrife plant from developing a flower stem. Almost the whole patch of loosestrife had some damage and future years of beetle activity should bring down the number of loosestrife plants.

Report a purple loosestrife growing site:

On-line form    Mail-in form

Lakehead Region Conservation Authority
P.O. Box 10427; 130 Conservation Rd.
Thunder Bay, ON  P7B 6T8 (Canada)
Telephone:(807) 344-5857  Fax:(807) 345-9156