Romancing the American Chestnut

  • American chestnuts (left) are smaller than Chinese and European chestnuts. The Chinese and European varieties are also resistant to the blight, making the imports more desirable to growers. (Photo by Lester Graham)

Food is always a big part of the holidays. But one
traditional food has – for the most part – disappeared from American tables. The Great Lakes Radio Consortium’s Lester Graham reports:

Transcript

Food is always a big part of the holidays. But one traditional food has – for the most part – disapeared from American tables. The Great Lakes Radio Consortium’s Lester Graham reports:


(Sound of Nat King Cole singing, “Chestnuts roasing on an open fire…”)


That old chestnut of a song romanticizes roasting chestnuts as a part of the holidays. But a lot of us have never even seen chestnuts, let alone roasted them on an open fire. Chestnuts used to be a major part of the Eastern hardwood forest. There were millions of them. In fact, 25 percent of all the mature trees were chestnuts. But a blight, imported with some Chinese chestnut trees, slowly wiped out the American chestnuts. Now, they’re gone.


Well… almost. Much of the root stock is still alive. Sprouts grow until the blight knocks them back again. A blight only hurts the standing tree where it branches out.


And, in a few isolated pockets in the Midwest, the blight hasn’t reached the trees. A few American chestnuts are alive and growing and some of them are free of the blight. At Nash Nursuries in central Michigan, owner Bill Nash is guiding us through a rare sight… a grove of American chestnuts.


“These are 20 years old and as you can see, they’re fairly good sized. The American chestnut is quite a rapid growing tree. It’s well-suited for our climate, so it doesn’t have any of the problems that some of the hybrids do as far as growing and cultural care you have to take care of them. The Americans, you get them started and they’re pretty much on their own.”


In a few places in Michigan and Wisconsin there are small groves of chestnuts. They’re prized trees. They’re great for shade. The hardwood is rot resistant and makes great furniture and fence posts. And the chestnuts are eaten by humans and wildlife alike. Bill Nash says the tree will be popular again if it ever overcomes the blight that’s hit it so hard.


“The American chestnut will make another big comeback in this country as a yard tree, as a timber tree, as a wildlife tree.”


That part about a wildlife tree is more important than just worrying about the squirrels and bunnies. Chestnuts were an important food source for all kinds of animals.


Andrew Jarosz is a plant biologist at Michigan State University. He says the loss of chestnuts has been hard on wildlife populations.


“Chestnuts shed nuts in a more regular pattern than oaks, which will have what are called mast years – where they’ll have major crops, massive crops one year and very small crops in other years – which means it’s either feast or famine if you’re depending on oaks.”


Since the blight first began hitting American chestnuts about a century ago, researchers have been looking into all kinds of ways to stop it. One way is to cross it with the Chinese chestnut which has a couple of genes that resist the blight. But it takes a long time to breed out the Chinese characteristics from the American chestnuts and still keep the resistant genes.


Another approach is genetic manipulation. Genetically modifying the American chestnut tree to make it disease resistant. Again, work is underway, but it takes a long time. And even after success, it’s likely some people won’t like the idea of releasing a genetically modified organism into the wild.


The final approach worked in Europe when the blight hit there. It seems there’s a naturally occuring virus that kills the blight. It spread naturally in Europe. There are a few groves in Michigan that have naturally acquired the virus and it’s working to keep the blight at bay. Andrew Jarosz is working on the research. He says the trick is figuring out how to get the virus to spread to other trees short of manually spreading it on cankers infected by the blight.


“If we’re literally talking about millions of trees across probably, you know, the eastern third of the country, we obviously can’t treat every canker on every tree. And we need to be able to figure out a way to deploy the virus in a way that it can spread.”


Even with all that hopeful research, it’ll be ten years at least before some practical solutions end up in the forests, and Jarosz believes a couple of centuries before the American chestnut holds the place it once did in the forests.


Bill Nash knows it’ll be a while before there are major changes, but he is optimistic about the American chestnut.


“Oh, I would think the tree has a bright future. There’s enough people working on that, enough programs going on now… So, I would suspect that in the not-too-distant future we should have some of this progress made. You know, Robert Frost in his poem predicted the comeback of the American chestnut, that something would arise to offset that blight. And we’re starting to see that.”


Frost put it this way: “Will the blight end the chestnut? The farmers rather guess not, It keeps smoldering at the roots And sending up new shoots Till another parasite Shall come to end the blight.”


Seems Frost was an optimist too.


For the Great Lakes Radio Consortium, this is Lester Graham.

Related Links

Odd Animal Behavior a Sign of Toxic Pollution

  • Odd animal behaviors have been noted in some birds, fish, and frogs. Researcher Ethan Clotfelter believes it may have something to do with exposure to toxic chemicals. (Photo by Sean Okihiro)

Toxic chemicals can sometimes be fatal to wildlife. Some researchers are now looking for more subtle signs of contamination. The Great Lakes Radio Consortium’s Mark Brush explains:

Transcript

Toxic chemicals can sometimes be fatal to wildlife. Some researchers are
now looking for more subtle signs of contamination. The Great Lakes Radio
Consortium’s Mark Brush explains:


Researchers are looking for birds that have a hard time standing up
straight, fish that are unusually aggressive, or frogs that seem a little
confused. These are signs that the animals might be affected by low-level toxic
contamination.


Ethan Clodfelter is a researcher at Amherst College. He studied data that looked at the behaviors of animals from all over the world. He says toxic chemicals that persist in the environment might explain why these animals are behaving oddly.


“What we really are trying to do is to come up with behavioral measures that
are good, sort of, early warning indicators. Because behaviors are very
highly variable kind of thing, and so you expect that even very small levels
of contaminants could induce changes in behavior long before you see six
legs growing out of frogs.”


Clodfelter says people, such as amateur bird watchers, have helped wildlife
officials identify odd animal behavior.


His review was published in the British research journal Animal Behavior.


For the Great Lakes Radio Consortium, I’m Mark Brush.

Related Links

Major Dock Corrosion Stumps Officials

  • The Duluth Seaway Port Authority's bulk cargo dock is typical of many in the port. Officials are troubled by corrosion appearing on the docks in the harbor - the steel is corroding much faster than normal. (Photo by Bob Kelleher)

Corrosion is eating away at the steel walls that hold one of the Great Lakes’ busiest harbors together. The corrosion is unlike anything known to be happening in any other Great Lakes port. But other port officials are being encouraged to take a closer look at their own underwater steel. The Great Lakes Radio Consortium’s Bob Kelleher reports:

Transcript

Corrosion is eating away at the steel walls that hold
one of the Great Lakes’ busy harbors together. The
corrosion is unlike anything known to be happening in
any other Great Lakes port. But other port officials
are being encouraged to take a closer look at their own
underwater steel. The Great Lakes Radio Consortium’s
Bob Kelleher reports:


Some kind of corrosion is eating away at the Duluth
Seaway port’s docks. The docks are those long
earth-filled metal rectangles where ships from around
the world tie up to load and unload. Those docks are
lined with sheets of steel, and the steel is rusting
away. Jim Sharrow is the Duluth
Seaway Port Authorities Facilities Manager.


“It’s corroding quickly – much faster than people expect
in fresh water. And our main concern is that we’ll lose
the integrity and the strength of the dock long before
expected, and have to do steel replacement at $1,500 or
more per lineal foot, much earlier than ever would have
been expected.”


Corrosion should be a slow process in Duluth’s cold
fresh water. But, Sharrow says, there’s evidence it’s
been happening remarkably quickly for about thirty years.


“What we seem to see here is corrosion that started in
the mid 1970s. We have steel that’s 100 years olds
that’s about as similarly corroded to steel that is 25
to 30 years old.”


It’s a big problem. There’s about thirteen miles of
steel walls lining docks in the harbor that serves
Duluth, Minnesota and Superior, Wisconsin. There’s half
again as many feet of wooden docks, held together with
steel pins. There’s corrosion on the legs of highway
bridges and the giant
steel ore docks that ship millions of tons of taconite
– a type of iron shipped to steel mills in Gary,
Indiana and Cleveland, Ohio.


“We characterize this as a 100-million dollar problem in
the harbor. It’s a huge problem, and what is so odd
about this is that we only see it happening in the
navigational area of the Duluth-Superior Harbor.”


The harbor links the St Louis River with Lake Superior.
Go a few miles up the river and there’s little corrosion
. So it doesn’t seem like the problem’s there. But, back
in the harbor, at the current rate of corrosion, Sharrow
says, the steel will fail quickly.


“I figure that in about 10 years at the current rate,
we will have to start replacing steel.”


“Particularly marginal operators could decide rather
than repair their docks it would be better for them to
go out of business, and we’re hoping that that isn’t
the case here.”


While the cause is a mystery, there’s no shortage of
theories. It could have something to do with stray
electrical voltage; water acidity; or the kinds of
steel manufactured in recent years. Chad Scott
discovered the corrosion in the late 1990’s. He’s an
engineer and a diver. Scott suspects
a micro-biological connection. He says there might be
something growing in small round pits that form on the
steel.


“We cleaned up the water. That’s the main thing –
that’s one of the main changes that’s happened since
the 70s, is we’ve cleaned up our water. We’ve cleaned
up our harbor, which is a good thing. But, when we
cleaned things up we also induced more dissolved oxygen
and more sunlight can penetrate the water, which tends
to usually promote more growth – more marine
microbiology growth.”


A team of experts met in Duluth in September to share
ideas. They came from the U.S. Navy, The Army Corp of
Engineers, and Ohio State University. And they agreed
there’s something odd going on – possibly related to
microbes or water chemistry. They also recommend that
other Great Lakes ports take a closer look at their
underwater steel. Scott says they at least helped
narrow the focus.


“We have a large laundry list right now. We want to
narrow that down and try to decide what is the real
cause of this corrosion. And these experts, hopefully,
will be able to get us going on the right direction,
so we can start doing testing that will identify the
problem.”


With the experts recommendations in hand, port
officials are now planning a formal study. If they
do figure out the cause, then they’ve got to figure
out how to prevent it. They’re in a race with
something, and right now they don’t even know with
what.


For the Great Lakes Radio Consortium, I’m Bob Kelleher.

Related Links

Congress Approves Asian Carp Barrier Funding

  • U.S. Fish and Wildlife Service catch an Asian carp. This invasive species can grow up to four feet long, and the U.S. House and Senate have agreed to supply funds to try to keep them out of the Great Lakes. (Photo courtesy of U.S. Fish and Wildife Service)

The U.S. House and Senate recently passed a bill that will help keep Asian carp out of the Great Lakes. As the Great Lakes Radio Consortium’s Celeste Headlee reports, the federal government will contribute nearly two and a half million dollars to help repel the fish:

Transcript

The U.S. House and Senate recently passed a bill that will help keep Asian carp out of the Great Lakes. As the Great Lakes Radio Consortium Celeste Headlee reports, the federal government will contribute nearly two and a half million dollars to help repel the fish:


Asian carp are huge, often growing to be four feet long and weighing 80 pounds. They are also extremely prolific and voracious. Most Asian carp consume up to 40 percent of their body weight every day. There is currently an electric fish barrier strung across the bottom of the Chicago Sanitary and Ship Canal to keep the fish out of the Great Lakes. The barrier creates an underwater field of electricity that repels the carp.


Andy Buchsbaum is the director of the National Wildlife Federation’s Great Lakes Office. He says the current barrier is temporary and due to fail next year.


“Today the Great Lakes really dodged a bullet. Right now, the carp are poised 20 miles away from the failing barrier, which is just downstream from Lake Michigan. And if that barrier fails, then essentially the Great Lakes as we know them are over.”


The U.S. House and Senate passed a bill that will supply 75 percent of the funds for building a new barrier. The Great Lakes governors have agreed to supply the rest of the money. President Bush has said he will sign the bill when it reaches his desk. Buchsbaum says the new barrier can be completed within 60 to 90 days.


For the Great Lakes Radio Consortium, I’m Celeste Headlee.

Related Links