Insect Death Match

  • Researchers want to bring in parasitic wasps from China to kill the emerald ash borer (pictured) to slow the beetle's spread. (Photo courtesy of the USFS)

The federal government wants to import insect parasites from China into
the US. Rebecca Williams reports officials are hoping parasitic wasps
will control a pest that’s been killing millions of trees:

Transcript

The federal government wants to import insect parasites from China into
the US. Rebecca Williams reports officials are hoping parasitic wasps
will control a pest that’s been killing millions of trees:


The emerald ash borer has already killed 20 million ash trees.
Scientists think the ash borer got into North America in cargo from
China. It came over without any of the parasites that normally keep it
in check.


Researchers want to bring in some of those parasitic wasps from China
to try to kill the ash borer beetles.


Juli Gould is with the US Department of Agriculture. She’s been
studying the parasitic wasps. She says the ash borer can’t be
eradicated, but the parasites might slow the beetle’s spread:


“The population is very widespread right now and we need another tool
in the toolbox to help control it.”


Gould says they’ve been running tests to make sure the parasitic wasps
won’t kill insects other than the ash borer. She says in her lab
tests, the parasites appear to much prefer ash borers over the other
insects they tested.


For the Environment Report, I’m Rebecca Williams.

Related Links

Lessons From Insect Infested Wood

  • A team of horses drags a dead ash tree through the woods to be milled into usable lumber. Tens of millions of ash trees have been killed by a bug imported from China called the emerald ash borer. (Photo by Lester Graham)

Ash trees are dying by the millions because of an infestation of a
foreign bug. In one town, they’re using the dead wood to help build a
library. Lester Graham reports the wood beams and flooring will be a
permanent exhibit to remind visitors of the trees that were once there
and the cost of imported pests:

Transcript

Ash trees are dying by the millions because of an infestation of a
foreign bug. In one town, they’re using the dead wood to help build a
library. Lester Graham reports the wood beams and flooring will be a
permanent exhibit to remind visitors of the trees that were once there
and the cost of imported pests:


Craig Novotney is driving a team of black draft horses, some young
Percherons, through a wood lot. They’re dragging a pretty good sized
log out into the open to be trucked away and turned into lumber. They
could have used a bulldozer to do this job, but that would have damaged
a lot of the other trees in these woods:


“It’s a lot less impact on the forest floor. You don’t ruin near as
much stuff, you know, getting it out with horses. It’s a kind of
lighter approach to it.”


Sixty ash trees have been cut down on this four-acre piece of land.
They were all dead, killed by a bug called the emerald ash borer. The
wood from these dead trees will be used to make flooring, wood trim,
and to be support beams for a new branch library.


The architects knew they wanted to use ash, as a way of reminding
people of this disappearing natural resource. But it was the flooring
contractor who suggested the ash wood they needed was on the very
property where the library is to be built.


John Yarema owns Johnson Hardwood Floors:


“We were originally came out to look at flooring and ash. And when we
told them we could use the material off the site, they were excited.”


Rather than just flooring, Yarema suggested the architects use the dead
ash trees for some of the structure of the building, so that people
could see the damage the emerald ash borer had done, a sort of
permanent exhibit.


“One wall – it’s a 90 foot wall facing the woods – all glass. So, in
front of that, we’re going to have trees, emerald ash borer-killed
trees supporting that wall.”


The trees will still bear the marks of the damage done by the bug.
The ash tree is a popular tree, but like this place where they’re
chopping down the trees, city after city has had to cut down all of
their ash trees in an effort to stop the spread of the emerald ash
borer.


Despite efforts to quarantine infested areas, the emerald ash borer
is spreading. It was first detected in Michigan in 2002. It probably
came in shipping crates from China. The pest already has spread to a
half dozen other states and Ontario. The bug is being spread in part by people
hauling firewood with them on vacation and hunting trips, and in some
cases by nursery stock being shipped out of the area.


Josie Parker is the Director of the Library District in Ann Arbor,
Michigan where this new branch library is being built.


“Because it’s a public building, it will tell the story of what can
happen and did when there’s an infestation. This building will always
be here. The emerald ash borer tracings will be evident in the wood.
So, we’ll be able to explain (to) science classes and anyone who’s
interested what happened to ash trees and why we need to be more
careful about insect infestations.”


A lot of the dead ash has been cut up for firewood. But some people
have felt that the wood shouldn’t be wasted. It should be preserved
somehow. John Yarema says it makes him sad, seeing the ash tree
disappear. But, he likes the idea of using these ash trees in a way
that might serve as a lesson:


“It’s nice in the sense that it’s in an educational facility and not
chopped up into firewood. So, in that way, you feel better than
burning it in a fireplace. If we can make a statement and maybe
somebody will look at it, maybe a child will look at it and say, you
know, ‘Wow, this is…’ because (in) 40 years there aren’t going to be
any. The only ash trees that’ll be around will be in the flooring, the
walls, the ceiling and in the structure. I think we just all need to
open our eyes and hope for the best, I guess.”


For the Environment Report, this is Lester Graham.

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Seed Bank Hopes to Save Trees in Peril

  • Examples of ash tree seeds that are part of the collection effort. (Photo by Lester Graham)

People have been saving seeds for thousands of years. Gardeners save
seeds of their favorite plants. Governments save seeds to protect
their food crops. Now, some people are freezing the seeds from trees.
That’s because the trees are being destroyed by an insect pest.
Rebecca Williams reports they’re hoping a gene bank will protect the
trees’ DNA and some day help bring the trees back:

Transcript

People have been saving seeds for thousands of years. Gardeners save
seeds of their favorite plants. Governments save seeds to protect
their food crops. Now, some people are freezing the seeds from trees.
That’s because the trees are being destroyed by an insect pest.
Rebecca Williams reports they’re hoping a gene bank will protect the
trees’ DNA and some day help bring the trees back:


Seeds are a pretty amazing little package. They might be small, but
they’re tough. They can live through very dry and very cold
conditions.


(Sound of seed being shaken out of a paper bag)


These seeds are from ash trees. In some parts of the Upper Midwest and
Ontario, ash trees have been wiped out. The seeds are all that’s left.
That’s because of the emerald ash borer. It’s a tiny green beetle that
got into the US in cargo shipped from China. So far, the beetles have
killed 20 million ash trees. No one’s been able to stop the beetles
from spreading.


David Burgdorf works for a lab with the US Department of Agriculture.
He says people might not even know they had ash trees until the trees
got attacked:


“If your lawn was filled with the ash tree and you had all this great
shade and your energy bills were low, but now the ash tree’s gone, you
only miss it when it’s gone.”


Burgdorf says a lot of people love ash trees for their gold and purple
fall colors. They grow fast and hold up well under ice storms. Native
American tribes depend on black ash for making baskets and medicine.


David Burgdorf is trying to make sure ash trees won’t disappear completely
if the beetle spreads across the country. He’s gathering ash seeds
sent in by volunteers. He’s hoping to build a collection that
represents the entire ash tree gene pool:


“We want to try not to have to bring something back. We don’t want it
to be extinct. It’s important we at least save the seed so we can maybe cross
it, or do something, breed in resistance to the tree and have it
available to come back.”


Burgdorf says he thinks of the seeds as an investment for the future.
The seeds are definitely being treated like a precious commodity.
They’re sorted and they’re X-rayed to make sure the living embryos in
the seeds haven’t been damaged.


Then, the very best seeds in the bunch are off to a high security
government vault:


“We kind of joke that it’s the Fort Knox for seeds.”


Dave Ellis is the seed curator at the National Center for Genetic
Resources Preservation. It’s a giant seed bank. Ellis says the ash
seeds are dehydrated and frozen at 0 degrees Fahrenheit. These steps
put the seeds into a deep sleep:


“In a dehydrated state, degradation of DNA happens much more slowly,
over a course of tens of years or hundreds of years.”


Ellis says the ash seeds should be viable for at least 25 years, if not
longer. He says researchers might be able to use the stored genetic
material to breed new pest-resistant ash trees in the future. Ellis
sees gene banks as a safeguard against a world that’s changing fast.


Scientists say wild plants and crops we depend on will face many new
threats. Climate change might bring more drought.
Escalating global trade could mean importing more pests.


Deb McCullough studies insect pests at Michigan State University. She
says any time you import cargo, you’re running the risk of also
importing pests that can run up huge bills. She says in North America,
one of the big concerns is imports from China:


“If you look at the latitude where China occurs, if you look at the
northern and southern latitude and you overlay that on top of the US and
Canada, it matches up almost perfectly. So you can figure that pretty
much any kind of climate or habitat you find in China, there’s going to
be something similar in the US.”


McCullough says not everything that gets in will turn out to be a pest,
but she says as China’s huge trade surplus with the US grows, there’s a
greater risk more pests will come in.


She says there are some new regulations in place, but restricting
international shipping is a tricky proposition. McCullough says seed
collecting might be one way to preserve plants we rely on:


“People who are molecular biologists, the gene jockeys, have gotten
very good at enhancing or producing resistant varieties of different
kinds of plants. So, that may be something that becomes an option in the
future, maybe not the too distant future.”


McCullough points out there will be serious debate about introducing a
genetically modified tree into the wild. Some people don’t like the
idea of manipulating the genetic makeup of plants or animals.


There are a lot of questions about what might be done with the frozen
seeds, but the seed collectors say regardless, they need to bank up the
DNA of plants that we’re in danger of losing.


For the Environment Report, I’m Rebecca Williams.

Related Links

True Costs of the Emerald Ash Borer

Officials in Michigan, Ohio, and Ontario are all gearing up for another summer of fighting the emerald ash borer. The Asian insect burrows into and kills ash trees. The economic and the environmental costs of the invasive beetle are adding up. The Great Lakes Radio Consortium’s Bill Poorman reports:

Transcript

Officials in Michigan, Ohio, and Ontario are all gearing up for another
summer of fighting the emerald ash borer. The Asian insect burrows
into and
kills ash trees. The economic and the environmental costs of the
invasive
beetle are adding up. The Great Lakes Radio Consortium’s Bill
Poorman
reports:


Researchers first identified the emerald ash borer just a couple of years
ago. The small, metallic-green beetle has killed millions of ash trees,
especially in southeast Michigan where thirteen counties are under
quarantine. Paul Bairley is the city forester for Ann Arbor, Michigan.
The
city is spending millions of dollars fighting the emerald ash borer. But
Bairley says, losing the trees has a significant environmental cost, as
well. Larger ash trees can provide enough oxygen for a family of four
for a
year, and other benefits.


“That same tree will provide the cooling value of about twenty
room-size air conditioners, BTU equivalents…and probably most importantly, air filtration
of pollutants. A car driven 11-thousand miles per year, that tree could
absorb effectively, recycle the exhaust from that automobile.”


Researchers think the emerald ash borer first arrived in the mid 90s
aboard
packing materials for goods shipped from Asian countries. For the
Great
Lakes Radio Consortium, I’m Bill Poorman.

Related Links

Invasive Insect Laying Waste to Area Trees

Scientists are working to control a new non-native beetle that’s destroying hundreds of thousands of ash trees in the Midwest. The Great Lakes Radio Consortium’s Erin Toner reports:

Transcript

Scientists are working to control a new non-native beetle that’s destroying hundreds of
thousands of ash trees in the Great Lakes region. The Great Lakes Radio Consortium’s
Erin Toner reports:


The Emerald Ash Borer is native to Asia, and probably made its way to the United States
through wood packing materials. Therese Poland is an entomologist with the
USDA. She says so far, the beetles have destroyed 100 thousand ash trees in southeastern
Michigan and southern Ontario.


“We think it’s been here for at least five years and even with some of the other exotic
beetles that have been discovered in recent years, when they were first discovered they
weren’t as widespread as this.”


Poland says there’s a quarantine over the infested areas to keep the beetles from moving
to new areas. Officials are inspecting nurseries to make sure they’re not selling infested
trees. They’re also checking whether tree care companies are disposing of trees properly.
But officials admit they probably won’t be able to stop people who unknowingly transport
infested firewood or yard waste.


For the Great Lakes Radio Consortium, I’m Erin Toner.