The War Against the Budworm

Abstract

In most years the spruce budworm is hard to find in the evergreen forests of New Brunswick—in one study (Morris, 1963), a thousand samples of treetop foliage yielded only ten budworm larvae in that Canadian province east of Maine. However, in an outbreak year, with its population swollen to as much as one thousand times that minimum level, budworm can devour all the new needles produced by a forest of balsam fir and ultimately can kill 80% of the mature trees in the forest. Such outbreaks have destroyed mature forests of balsam fir and damaged white, black and red spruce in eastern Canada and the northeastern United States every 30 to 70 years since at least the early 1700’s.