Alien Invaders of Our Forests

Watch out for the Big Three of Forest Pests in New Hampshire

Hemlock woolly adelgid.
Photo by Steve Roberge

If you’ve ever been horribly sick, you know the power of a tiny bug to cause harm and disruption.

Our forests aren’t immune from the power of tiny bugs. Even as sprawling and resilient as forests are, they face potentially enormous threats from small pests so small you could fit a bunch on a penny.

Three pests in particular deserve their mugs on a most-wanted poster for threatening our forests: emerald ash borer, hemlock woolly adelgid and Asian long-horned beetle. Those are the big three that foresters like Steve Roberge worry about.

“All three of these pests have the potential to change the way our forests look,” says Roberge, who lives at the N.H. Division of Forests and Lands’ Shieling Forest in Peterborough and is the UNH Cooperative Extension forester for Cheshire County.

All three have unique differences and affect trees and forests in different ways, according to Roberge and other foresters.

But they all share at least one commonality: They’re not native to North America. As such, our trees and forests lack the protective defenses against their potential harm. And as non-natives – with nature providing few elements to keep their numbers in check – they can spread like crazy if we’re not careful.

That’s why Roberge and others concerned about forest health want to spread the word about these big three. “The key to all three of these pests is early detection and an informed public,” Roberge says. “We should never let our guard down with all three of these. We want to have an informed public to make sure they know what these pests look like and what the signs of their damage look like.”

Early detection, Roberge says, can help prevent them from spreading and becoming a costly endeavor to eradicate.

So here’s a look at the big three:

Emerald Ash Borer

This little beetle from Asia was found in 2002 to be causing widespread mortality to ash trees in Michigan and Ontario. Larvae feeding on the tissue between the bark and the sapwood disrupt the flow of nutrients and water, eventually killing branches and the entire tree.

Since 2002, the emerald ash borer has killed tens of millions of ash trees as it has spread to 18 states, most recently in western Massachusetts in August. While not detected in New Hampshire yet, it has potential to seriously damage ash trees here, which are important part of our hardwood forests and provide an excellent source of heat for our homes.

Asian Long-Horned Beetle

A bit bigger than emerald ash borer, the Asian long-horned beetle is up to 1½ inches long, with very long black and white banded antennae. It is believed to have arrived in the U.S. in the 1980s via wood packing material coming into a port in Brooklyn. Since then, it has spread to many states and provinces and has been found in Worcester and Boston, Mass. In Worcester, tens of thousands of trees have been removed because of an infestation there.

Maples are a particularly favored host of the Asian long-horned beetle. If a serious infestation takes hold in New Hampshire, it could devastate maples, which are important to our maple sugar industry and are a critical part of our hardwood mix.

Hemlock Woolly Adelgid

This is a small aphid-like insect that feeds on hemlock and, if left untreated, can kill a hemlock within four to ten years, often by weakening the tree’s defenses from other pests. Introduced in Virginia in the 1950s, it has since spread from Maine to Georgia. And it’s already here. In our region, hemlock woolly adelgid has been found in Peterborough, Greenfield and Jaffrey.

The insect can be recognized by a dry, white woolly substance on the young twigs of hemlock. This woolly stuff is a defensive covering over the insect’s body.

While hemlock is often considered a species of low commercial value in New Hampshire, there’s no denying its importance to the ecosystem. Because of its habitat preferences and growth characteristics, the hemlock is like a forest’s ultimate shade and cover creator. It provides cover and habitat for white-tailed deer, wild turkey, fisher, porcupine, blackburnian warbler and many other species. It keeps forest streams cool for Eastern brook trout.

Losing hemlocks – or suffering impaired populations – could wreak havoc on the above species that are now fairly common. No other tree provides the same ecosystem service as the hemlock.

You Can Help

While it’s possible that these species will ultimately invade our forests, Roberge and other forest health advocates say we should not give up and should not let down our guard.

Owners of forestland can take many steps to protect to prevent, slow or limit the spread of nasty invasives. A key part in that is early detection through an informed public, not just foresters, loggers and land managers, but folks like you who enjoy the forest for all it provides.

Another step is to make sure you don’t inadvertently move forest pests via firewood. Pests can travel in firewood at various life stages, so don’t help spread infestations by buying untreated firewood from out-of-state or long distances, say 50 miles or more.

For more information about invasive forest pests, visit dontmovefirewood.org, or http://extension.unh.edu/fwt/cpestssub.cfm?sear=3. Also, check out this video: Trees, Pests and People.

Steve Roberge will give a talk on the “The Emerging Forest Pests in New Hampshire,” Thursday, December 6, 7 p.m., at the Keene State College Science Center. The talk is sponsored by the Harris Center for Conservation Education, the University of New Hampshire Cooperative Extension, and the Keene State College School of Sciences.

Eric Aldrich writes from his home in Hancock.

The Silence is Deafening

A Few Environmental Issues That Won’t Go Away

Since the presidential campaign began -- what seems like years ago -- we’ve been subject to a barrage of ads, signs, debates, news coverage and noise, noise, noise!

But when it comes to a handful of environmental issues, the silence is deafening.

Sure, environmental issues seldom reach the top of the issues list in presidential contests. But they have at least been the topic of one debate question or one point in a candidate’s case to American voters.

Not this time.

And it’s understandable that environmental issues would get lower billing than the enormous challenge of pulling our country out of recession and getting Americans back to work and prosperity.

But as Germany and many other countries have capably demonstrated, embracing green energy and environmentally friendly policies can bring new jobs and economic promise. The old argument of jobs vs. the environment is a false choice and at least one of the candidates knows this.

So why the silence on the green?

As one who’s always leaned more toward the natural sciences than political sciences, I can only offer speculation. Both candidates at this point in the campaign are trying to appeal to an endangered species: undecided voters, especially in those “key battleground states” like New Hampshire. They don’t want to ruffle any feathers of those rare voters by possibly alienating them with some language about energy-efficient light bulbs or global warming.

They want to play it safe. Naturally.

So here’s a little volume on just a few of the silent issues.

1. Climate Change. This, of course, is the biggie, the one neither side mentions in the campaign. As president, Obama has tried but failed to pass limits on carbon emissions, an effort that’s been a non-starter with a Republican-led House whose GOP members continue to ignore -- and mock -- the growing mountain range of scientific evidence about human-caused global warming. And Romney has back-pedaled hisonce tepid support for curbing carbon emissions. No matter who wins, this issue will challenge the next president, not only in terms of global warming’s ever-growing impacts on civilization, but also what we’re going to do about it.

2. Saving Our Lands. This has never a big topic on the presidential campaign, for sure, but in practice, the notion of safeguarding America’s precious landscapes -- at the national and local level -- has always been dear to our hearts. National surveys have confirmed this many times: No matter the party affiliation, Americans believe that “conserving our country's natural resources ‐ our land, air and water ‐ is patriotic.” But House Republicans have proposed drastic funding cuts to programs like the federal Land and Water Conservation Fund, which has funded such projects as additions to national parks and land-protection projects here in the Monadnock Region. The next president may have an opportunity to lead this argument back to the direction of Americans’ desires.

3. Energy Conservation. As president, Obama has pushed greater fuel economy standards for new vehicles. In his campaign, Obama has mentioned many times the need to broaden our energy mix toward wind, solar other clean energy sources. And while Romney gives quiet support toward a green energy mix, his rhetoric leans toward more domestic development of oil, coal and gas sources. But both candidates have said little about energy conservation -- the energy that we don’t use is energy that we don’t have to develop. The next president may have an opportunity to encourage more energy savings.

4. Clean Air & Clean Water. Signed into law by President Nixon, the Clean Air Act has not only spared the air of millions of tons of toxins, it has prevented an estimated 200,000 premature deaths and thousands more the harmful impacts of bronchitis and other diseases. Heavily funded by oil and coal companies, House Republicans have led an all-out effort to weaken the Clean Air Act in many ways, including measures that would curb carbon pollution. The Clean Water Act is celebrating its 40th anniversary this year and facing a similar assault by House Republicans. This comes at a time when science is showing that, while many rivers have improved, estuaries from New Hampshire’s Great Bay to Long Island Sound are increasingly threatened by nitrogen pollution. President Obama or Romney will have to decide whether we continue cleaning our air and water or whether we leave it to the next leader.

5. Endangered Species. Also signed into law by President Nixon, the Endangered Species Act is now deeply flawed, often unworkable and outdated from gains in conservation science. But as troubled as the law is, it has helped bring back the bald eagle and other species. Many terms of Congress have kicked sorely needed changes to the law to an uncertain future, while dozens of species continue sliding toward extinction, even species once common as the little brown bat. Ignoring the act -- along with its troubled political fallouts -- won’t do anything to help species sliding down the biological drain. Political courage from the top could reverse this troubling trend.

No matter who wins on Nov. 6, the environment has long been a priority among New Hampshire-ites and Americans. When the victor emerges and a new Congress gets settled, feel free to remind them that a few issues that were silent during the campaign will soon deserve a little more noise.

Eric Aldrich writes from his home in Hancock.