When people think of forests with big old trees, we usually think of the West Coast. Here in New England, trees are naturally shorter, and loggers have been cutting the forests for hundreds of years, so many people think we never had big old trees, or, if we did, they are now all gone.
Fortunately, that is not the case … yet.
Scientists from the Manomet Center for Conservation Sciences have recently found that stands of old trees still exist, scattered throughout the vast industrial forest of northern Maine. These are stands of trees ranging from a few acres to hundreds of acres in size that contain some trees 100 to 200-plus years old.
Scientists call these stands of big old trees “late-successional” forest. These forests have not been significantly changed by fire, blow downs or harvesting for many decades.
Although no one yet knows how many big old forests still exist in northern Maine, the ones that remain are rapidly disappearing. Manomet scientists predict that these stands will be functionally eliminated from the working forest within five or 10 years unless something is done to conserve them.
The reason these old forest stands still exist, sprinkled throughout the northern half of the state, is because they were last cut more than a half-century ago, and then only for a few tree species that had market value at the time. Today these stands have trees well over 100 years of age that survived the last harvest.
But times have changed. Now all tree species have market value. Now virtually every acre of Maine’s forest is accessible by logging roads. Now, many timber companies believe that it is a losing proposition to grow trees past 70 years of age. And thus, these stands left over from another time have been vanishing, quietly, without notice.
Fortunately, ecologists are beginning to understand the special ecological qualities of old forests in New England. In Scandinavia, many plant and animal species are threatened or endangered because of the loss of older forests. Many of the most vulnerable species are not charismatic, or even recognizable but they are critical to a healthy forest. They are mosses and lichens and fungi that seem to prefer to grow on large, old, living and dead trees.
Over the past 50 years, harvesting practices in Maine’s North Woods have tended to take the older trees, leaving a younger forest – what some have dubbed a “teenage” forest. In these younger forests species that depend on big old trees become threatened, then endangered, and begin to disappear from the landscape. In addition to the ecological problems, creating endangered species can create a whole new set of challenges.
To their credit, some of Maine’s major forest landowners have provided initial funding to Manomet, to develop an index to help foresters identify older forest stands in the field. To use the index, foresters will need to learn about a handful of easily identified mosses and lichens. They will then be able to “score” the stand indicating whether it contains a lot of the characteristics of a big old forest or only a few. Once foresters have scored the stand, they can adjust harvesting plans to avoid harvesting high-scoring stands, or cut them in a way that protects the value of the stand.
Although we have had many battles with the forest industry in Maine over the years, some of which continue today, I am hopeful on this particular conservation issue.
The rest of this story, of course, is yet to be written; the outcome will depend on the fate of Maine’s remaining old forests in the next few years. Hopefully we will be able to say: going, going … saved!
Catherine B. Johnson is North Woods Project Director of the Natural Resources Council of Maine.