From The Record

Feb. 10 , 2008

Least of N.J. forests' worries

BY EMILE D. DEVITO

Strictly from an ecological point of view, gypsy moths have no significant long-term negative impact on the value of a forest.

RECENT NEWSPAPER articles would lead the public to believe that gypsy moth outbreaks are ecological catastrophes. The fact is, these outbreaks have happened four times in the last 35 years on New Jersey's public lands, and hardly anyone can tell the difference.

True, a gypsy moth outbreak can leave an unsightly, totally leafless patch of trees during June and July. But aside from valuable residential shade trees and commercial timber production (which is minimal in New Jersey), our forests are actually none the worse for the wear.

Strictly from an ecological point of view, which considers all animals and plants in a forest, although individual trees are weakened and some even die, gypsy moths have no significant long-term negative impact on the value of a forest. Even if a large proportion of oaks were to die across thousands of acres, the next generation of trees would be a more diverse set of species, and the forest would eventually end up more varied and resistant to future mass defoliations or diseases brought by alien species.

We cannot currently do anything to alter the biology of a gypsy moth population. Their cycle is controlled by rainfall, temperature and natural pathogens and parasites. Spraying a relatively small percentage of their vast forest habitat will not change anything except the cosmetic appearance of a patch of forest. Gypsy moths will always return every few years, even if the banned chemical Dimilin is reauthorized, as some are currently proposing.

Dimilin – a known carcinogen and a suspected human endocrine-system disruptor – is far too dangerous. Further, Dimilin must not be used anywhere near wetlands and waterways. This chemical is broad-spectrum, killing not just gypsy moths but all insects, including bees, as well as all other arthropods, such as spiders -- the very base of the forest food chain.

In places where gypsy moth damage control makes sense -- intensive recreational areas such as campgrounds, where dead trees can pose fire hazards -- the biological agent known as BT (bacillus thuringiensis) is the only logical option, especially in areas frequented by people.

Except in residential areas and places like campgrounds, Gypsy moths should be way down on the list of species to worry about. Asian long-horned beetles, Japanese stiltgrass, Chinese bush clover, barberry, Oriental earthworms, wooly adelgids, emerald ash borers, and many other species pose threats that are orders of magnitude greater than that of the gypsy moth.

The greatest threat to all our public and private forest land is an overabundance of native white-tailed deer eating the lower levels of the forest – the next generation of trees, shrubs and wildflowers. This, in turn, is opening areas up for invasion by non-native plants that crowd out their native counterparts. It is this next generation of our forests that is being rapidly lost, and society is not yet aiming significant resources at rescuing the hundreds of species that are disappearing.
Let's make sure we see the forest for the trees and keep some perspective when we consider the gypsy moth problem.

Emile D. DeVito, from Far Hills, is manager of science and stewardship for the New Jersey Conservation Foundation.

From NorthJersey.com/The Record

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