Spruce budworm has shaped not only Maine’s forests, but its history, economy, laws, and culture.
Budworm infestations, which actually kill more fir than spruce, go back a long way. Through macrofossil analyses at a bog in Saguenay, Quebec, Canadian researchers have tracked budworm back more than 8,000 years. Its Maine history probably started later since until 1,000 to 1,500 years ago, spruce and fir were limited to Maine’s coastal areas, while hemlocks dominated interior forests. Then the climate cooled, spruce-fir expanded and hemlocks receded at what was, for a natural phenomenon, breathtaking speed. In just three or four centuries Maine essentially became a spruce-fir state.
Cyclical Infestations
Through tree ring studies of virgin stands and the beams in historic homes, budworm outbreaks in eastern Quebec have been charted since 1577. Researchers here found infestations in Big Reed Forest Reserve in 1709, 1762, 1808, 1914, and 1976, and other infestations are noted in historical accounts.
By the 1909-1918 infestation, technology had been developed to make paper from wood. Maine had about 35 paper mills in 1900 and forests were changing. Spruce was the wood favored for pulp, and its removal allowed balsam to regenerate rapidly and thus crowding out the spruce. Conditions were right for a severe budworm infestation, and browning of the spruce and fir needles was evident in the winter of 1916-17, leading to a rush to harvest before the trees were killed. Within 5 years approximately 40 percent of the spruce and 75 percent of the fir in the whole state was dead (about 27.5 million cords of wood).