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[dete49]

Black Flies become a major problem in late June and August. Mosquitos are a serious pest throughout the arctic, but are a major problem near the tree line, day and night and in all weather conditions.
Black Flies are a major problem in most of forested Canada from early May until mid-June. Further north in the boreal forest they may be present in all of June and July. Mosquitos of different varieties may be a serious pest in most of Canada from early spring until early fall, especially near marshes.
Lake of the Woods Black flies generally a problem from late May to July. Mosquitos a problem most of the summer, although by late August the dragonflies and bats have eaten in the numbers. The serious problem is in the woods, in the open or on the water "not bad" Deer flies and nitng midges not a problem. Another difficulty is the army worms that become extremely numerous on a ten year cycle, with a three year serious period. Last year was worst, this year should be better and they should largely be gone for a few years.