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Fig. 11, tracks spruce-fir growing stock volume in Maine’s forests from 1902 through 1995. Inventory was at its lowest point in 1933—a result of two factors: a heavy harvesting cycle that slowed at the end of World War I and the 1912–1920 budworm outbreak. Wood utilization standards have changed significantly over the years, so the earliest inventory data is not comparable to current data. However, its reflection of the spruce-fir life cycle is accurate. Source: “Condition and Outlook for Maine’s Spruce-Fir Forest,” The Irland Group, February, 1998; and the Maine Forest Service.

Maine’s spruce-fir forests are products of a convergence of human and natural events. Between 1890 and 1920, the state’s softwood forests experienced very heavy cutting. The nation’s economy was growing rapidly, and Maine’s forests provided an enormous amount of wood for residential and commercial building. The impact of 30 years of heavy harvesting was exacerbated by a spruce budworm outbreak that occurred between 1912 and 1920. This combination of events—the heavy harvest and the budworm outbreak—set in motion the cycle of natural regeneration (Fig. 11) that created the spruce-fir forests that dominated Maine’s landscape until the 1970s when a devastating spruce budworm epidemic necessitated another cycle of heavy cutting. The outbreak lasted 15 years (1970–1985) and unleashed a storm of criticism from citizens who were angered by the amount of clearcutting that occurred.

“People were angry,” reports Lloyd Irland, owner of The Irland Group, a Winthrop, Maine, forest consulting firm. “It all happened so fast. Spruce-fir forests that had become Maine landmarks were harvested on an unprecedented scale. Some of the clearcuts were adjacent to heavily traveled roads. It was not a pretty scene.”

The budworm infestation hit spruce-fir forests so hard that growth collapsed for more than a decade. Between 1975 and 1990, budworm-related mortality in balsam fir exceeded both gross growth and harvest. (Fig. 12) Red spruce fared better, as did the hardwood species. In all, between 20 and 25 million cords of spruce and fir were killed, though much of it was salvaged.

Spruce budworms are very efficient killers. Though their name implies a preference for spruce, they will also attack balsam fir. They begin their work in treetops, invading buds and cones first. Then they parachute into the understory below, where they attack seedlings and saplings.

“They are hell on regeneration,” Mr. Irland says. “In a serious outbreak, like the one we experienced in the 1970s, about all a landowner can do is pick up the pieces and start over.”

In a February report, “Condition and Outlook for Maine’s Spruce-Fir Forest,” Mr. Irland suggested that had landowners elected not to aggressively salvage dead and dying spruce and fir, balancing growth against harvest and mortality would have required much of the industry to shut down by the late 1970s. “In retrospect, such a sacrifice would not have helped much because the budworm outbreak was concentrated in mature, short-lived balsam fir,” he explained. “Thus, growing stock volume would have declined even if no salvage harvesting had occurred. Though it created a momentary eyesore, salvage logging was likely the lesser of two evils if only because it gave landowners the opportunity to recover their capital.” Since 1982, the region’s paper companies have invested more than $90 million in treating some 900,000 budworm-damaged acres. Herbicides were applied to control growth in competing vegetation long enough to give new naturally regenerated spruce and fir an opportunity to overtop brush. Overly dense spruce-fir stands were thinned and, where necessary, entire stands were replanted by hand.

When it calculates growing stock volume, the U.S. Forest Service does not include volume or growth data for trees smaller than five inches in diameter. In Maine, it takes from 20 to 25 years for spruce or fir to attain such size, so the industry did not get credit for its post-epidemic investments in the agency’s 1995 survey.

“It’s unfortunate,” Mr. Irland says. “The public has been left with the perception that growth and harvest are way out of balance in Maine. Harvest exceeded growth when landowners were out battling budworms, but current indications suggest that spruce-fir harvest is probably in balance with long-term average growth.”

Fig. 12 , tracks mortality as a percent of gross growth and removals for 1982–1995. By far, the heaviest losses occurred in balsam fir. Source: Data by the U.S. Forest Service and calculations by The Irland Group.

It would seem so. One landowner Mr. Irland is assisting estimates its new immature stands are growing at a rate of 1.15 cords per acre per year—twice the state average measured before the budworm outbreak. Another reports growth in surviving mature spruce-fir forests has doubled since the budworm infestation subsided.

Softwood timber harvesting in Maine has been declining since budworm-related salvage cutting peaked in 1985. Other factors have kept the harvest below its 1985 peak. Increased use of hardwood has enabled the industry to maintain output despite a decline in softwood usage. Recycling is playing an increasingly important role, allowing mills to reuse fiber rather than harvest new wood. Advanced sawing technologies are also helping, enabling mills to use smaller logs that were once considered waste.

As the budworm epidemic has subsided and productionrelated factors have begun to exert their own influences, clearcutting has given way to a wide array of partial cutting techniques. The Maine Forest Service reports that since 1989 the number of acres clearcut has declined from 45 percent to 11 percent of total acres harvested. (Fig. 13) Nevertheless, there is no denying that, during the worst of the epidemic, a few landowners took advantage of the crisis—liquidating forests that were not infested or had suffered only minor damage.

“Their actions made it tougher for other landowners who were really struggling to get ahead of the budworms,” Mr. Irland says. “Unfortunately, not all landowners share the same conservation ethic.”

Fig. 13 , tracks the decline in clearcutting in Maine from 1989 through 1994. As clearcutting has declined, it has been necessary to partial cut more acres to produce the same harvest volume. Source: Maine Forest Service

Though the worst is over, there is not enough data available to determine what sort of harvest level is sustainable in the foreseeable future. The U.S. Forest Service and the Maine Forest Service are conducting an in-depth review of current data, and a report is expected later this year. Preliminary estimates suggest that softwood harvest levels of the past several years are sustainable, but these estimates are based on growth and harvest modeling assumptions that have yet to be fully tested. There is additional concern for the fact the budworm outbreak and the resulting salvage harvest have at least temporarily decreased the acreage of Maine’s spruce-fir forest.

“We know acreage typed as spruce-fir declined during the budworm outbreak,” Mr. Irland explains.“What we don’t know is what forest type will replace it. We may see another spruce-fir forest right away, or hardwoods may become more dominant for a while. We don’t know for sure.”

For the time being, it appears that yield-increasing intensive forestry—which has already cost landowners more than $90 million—offers the best hope for restoring Maine’s spruce-fir forests.

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