Changing New England Forests

100_2950Most of us would be amazed if we were suddenly transported back through time to observe the landscape in late nineteenth century New England.  We would probably have difficulty recognizing many parts of our own region.  Where mature forests now exist we might see large, clear, open spaces separated by field stone walls and lightly forested hedgerows.  In fact, from high vantage points we would be able to see thousands of cleared acres around us, including meadows and agricultural fields in surrounding communities.  New England, now roughly 80% forested in the central regions, has changed from agrarian communities to communities that are comprised of commuters who travel to work in nearby cities and towns.  Pastures left fallow inevitably turn into shrub meadows and eventually into forests.  Barring major fires, as the forest matures it begins to represent what the natural New England landscape might look like without human influence. Or does it?


Few, with the exception of foresters, ecologists, and naturalists might recognize that the evolving New England forest is something quite unexpected.  Direct and indirect impacts from human influences have altered not only the selection of tree species in our forests, but the ecosystem that may determine which may determine which plant and animal species might reside in these temperate forests. In the last seventy years the New England forest has had to endure hardships and difficulties for which humans are responsible.  Our might American Elm, an important cavity tree for birds and mammals has been all but eradicated by Dutch Elm Disease.  The regal American Chestnut, one of the largest and most important hardwoods in the deciduous biome is nearly extinct.  This huge forage producer and important nesting tree is limited to only a handful of saplings that grow back from old Chestnut root systems until they contract the Chestnut blight disease that was introduced by Chestnut trees imported from Asia almost 100 years ago.  The American Beech, battling against Beech Bark Disease, is now profoundly unhealthy and in short supply as compared to a few decades ago. This forage tree is amongst the important mast producers, producing crops of Beechnuts that are utilized by many kinds of wildlife. 


To add to the severe woes of the forest acid rain has wreaked havoc with White Ash, Sugar Maple, and a variety of Spruce populations.  White and red oaks have withstood severe infestations of gypsy moths that seem to revive themselves at least once each decade.  The gypsy moth appears to be an offcast of a failed silk making experiment.   Sugar maples are frequently weakened by maple thrips, a small insect capable of defoliating a tree in a single month.  Another serious pest is the wooly adelgid which defoliates our Eastern Hemlock an important tree for warbler nesting and winter white tailed deer yards.  This pest, a native of Asia, is threatening millions of acres of Eastern Hemlock along the eastern seaboard and within inland areas. 


The newest threat and perhaps the one that could have the greatest deleterious impacts is the introduction of the asian longhorn beetle.  This pest, likely brought from China or some other Asian country in uninspected shipping containers, has the potential to severely impact the entire New England hardwood forest.  Recently discovered in Worcester, Massachusetts, state, federal, and local  officials are removing thousands of trees of scores of square miles in hope of eradicating this harmful pest before it spreads to the major hardwood areas of Western Massachusetts, Vermont, New Hampshire, and Maine.  This beetle has the potential to ruin the sugar maple industry, autumn foliage tourism, private woodlots that raise hardwoods for saw logs and cordwood, and commercial forestry businesses. 


It is interesting to examine how human neglect has introduced all of these diseases and pests into our natural landscape.  It is doubtful that any of this was intentional.  Rather a misunderstanding of just how fragile the forest ecosystem really is has contributed, heavily, to these ecological problems.  The importation of non-indigenous species (those form a different area) is perhaps the best example of human unintended influence.  A particular tree may tolerate a native blight or insect without too much harm because the two species have had thousands of years to adapt to one another.  That same tree might have no defense mechanism to thwart a disease or pest from a different  region.  Evolution provides an equal number of changes and solutions. Human influences (like introducing a foreign pest) simply provide change without the benefit of solutions.    When humans do attempt to provide solutions for their mishaps they tend to upset the ecological apple cart even more and in some other way.


The future of the New England forest is a mystery to all.  Certain species like the Red Maple have replaced, very aggressively, some of the lost tree species of our region.  Although Red Maples have many fine habitat attributes they simply cannot replace all of the the unique habitat attributes of the trees that are in peril or have been lost.  The key to most healthy ecosystems is species diversity.  We need a well rounded native forest for our regions overall ecological health.


It must remembered that some of brightest minds are working on this problem.  First, we have identified the problem.  The introduction of foreign pests and diseases is the primary cause of our forest’s decline.  Second hybrid elms, chestnuts, and the improvement of other impacted tree species are all underway.  The reintroduction of these plants into our forest ecosystems has the potential to resemble the native New England forest and many of its natural characteristics.  Increasingly, we are learning that humans must walk lightly in the natural world to perpetuate the earth’s natural processes that are as close to perfect as one could imagine.  Our human culture is now appreciating certain habitats and designating these some of these areas as “wild forever”.  And most important our children are learning, at a much earlier age than we did, that humankind is an integral part of a very delicately balanced living organism called Earth.


Originally written for the Heath Herald in March of 1991, updated with more current information in May 2009.

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