Tag: aspen

Trees Under the Influence of Ozone and Co2

  • The circle of trees, as seen from the outside. The white pipe seen near the top delivers either normal air, one, or both of the experimental gasses to the trees. (Photo by Bob Kelleher)

In northern Wisconsin, they’re finding that gasses such as carbon dioxide and ozone will change the makeup of what survives in a future forest. An open air experiment called the Aspen FACE project has been testing trees in elevated levels of ozone and carbon dioxide for ten years. But they don’t know whether the forest can change as quickly as the climate does. The GLRC’s Bob Kelleher has more:

Transcript

In northern Wisconsin, they’re finding that gasses such as carbon dioxide and ozone will
change the makeup of what survives in a future forest. An open air experiment called the
Aspen FACE project has been testing trees in elevated levels of ozone and carbon dioxide
for ten years. But they don’t know whether the forest can change as quickly as the
climate does. The GLRC’s Bob Kelleher reports:


We’re standing inside a circle of trees: paper birch, aspen, and sugar maples, maybe 15
feet high. And they’re surrounded by a ring of large white pipes spraying the trees with
gasses – that’s the high pitched noise.


Among 12 different circles of trees, some get carbon dioxide, or ozone, or a
combination. These are the very gasses believed responsible for changing the climate –
they hold in the earth’s warmth, forcing surface temperatures higher.


Dave Karnosky, with Michigan Technological University, heads the Aspen FACE project,
near Rhinelander, Wisconsin. Karnosky’s trying to predict how these gasses will affect
the northern forest:


“Those species, with aspen and aspen mixed with birch and maple make up a huge
portion of our northern forests, and there was a lot of interest by industry as well as to
what’s going to happen in the future as these greenhouse gasses continue to build up in
the atmosphere.”


Even ten years ago, when this project started, it was clear that carbon dioxide and ozone
levels were on the increase.


Ozone is destructive. It’s bad for people and for plants. Carbon dioxide, on the other
hand, is what we exhale, and what green plants need to grow. Both gasses have been on
the increase, largely due to burning fossil fuels such as in coal-fired power plants and in
cars and trucks. Karnosky says he knew aspen were quite responsive to both CO2 and
ozone:


“We weren’t sure much about the interaction, but we were sure interested in what would
happen with that, because those two pollutants are both increasing at about the same rate
in the atmosphere.”


The Aspen FACE project has shown that most trees grow well when exposed to carbon
dioxide, and most do poorly in ozone. With the gasses combined, bad effects tend to
offset the good ones, but results vary greatly between the different kinds of trees, and
even within a single species of trees, like aspen.


Karnosky has found there’s a tremendous range of genetic variation even among the
relatively few trees they’ve tested. That variation makes clear predictions difficult:


“It’s very tough to make a single prediction for species or individuals within species,
there’s so much genetic variation. So that’s been one of the, I think, kind of the highlights
from what I see in terms of a bit of a surprise for us.”


That genetic variation could be the forest’s salvation. Karnosky thinks that if some
aspens, for example, die off from ozone, maybe others will do okay, and fill the forest
back in. Sugar maples, which seem more tolerant of ozone, could replace some aspen
and birch. Then, the mix of trees in the forest would change, but the forest would
survive.


But, there could be problems if the air changes the forest too quickly. Neil Nelson is a
plant physiologist with the US Forest Service. Nelson says the region’s paper and pulp
industries rely heavily on aspen trees. He’s uncertain how quickly the forest, and forest
industry, can respond if aspen begins to die off – and how long it might take for other
trees to grow in.


“One of my colleagues has said, you know, the key issue may be whether things change
too fast for our society and economy to adjust to, and I think that’s an open question.
There seems to be great plasticity, and we aren’t quite there in terms of predicting from a
forest management standpoint what these results mean.”


It takes time to grow trees, maybe too much time if the climate suddenly shifts. The
Aspen FACE project has already provided regulators preliminary data on ozone. It could
become the basis for future pollution law. But, even ten years into the Aspen Face
project, there’s still a lot more data to harvest among the aspen and hardwoods.


For The GLRC, I’m Bob Kelleher.

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Outdoor Lab Forecasts Global Warming Effects

  • Mark Kubiske checks the valve that controls the flow of greenhouse gases to a stand of sugar maples, birch and aspen. (Photo by Jennifer Simonson)

Scientists from around the world are studying how higher levels of carbon dioxide will affect forests 100 years from now. They’re doing that by pumping higher levels of CO2 and ozone into stands of trees. The Great Lakes Radio Consortium’s Mike Simonson visited the experimental forests and has this story:

Transcript

Scientists from around the world are studying how higher levels of carbon dioxide will affect forests 100 years from now. They’re doing that by pumping higher levels of CO2 and ozone into stands of trees. The Great Lakes Radio Consortium’s Mike Simonson visited the experimental forests and has this story:


(sound of “quiet area”)


The north woods of the Great Lakes states are stands of millions of acres of pine, maple, birch, and aspen forests. It’s a perfect place to try to figure out how trees will react to the higher levels of ozone and carbon dioxide scientists expect in the future.


(sound of beeping fence gate)


The first thing you notice at Aspen Free Air Carbon Dioxide Enrichment Project – Aspen FACE for short – is two huge tanks inside the fenced in enclosure. Each one is bigger than an 18-wheel tanker truck. They’re full of carbon dioxide… CO2. So much CO2 is used in this experiment, the tanks are filled twice a day.


(sound of filling tanks)


If you looked at the site from an airplane, you’d see 12 circular tree stands surrounded by 30 foot high pipes. Those pipes pour CO2 or ozone gases or both into the air surrounding birch, sugar maple, and aspen trees. The scientists know that greenhouse gases in the earth’s atmosphere have been increasing. They believe two centuries of industrial pollution has contributed to the problem. And they expect the CO2 and ozone levels to double by the end of this century. They’re raising the level of greenhouse gasses in different mixes to see what the predicted levels will do to forests.


This open air project is different than previous experiments. David Karnosky is with Michigan Tech. He’s the Project Manager for Aspen FACE. He says before these kinds of projects, they just tested trees inside places like greenhouses.


“We needed to get out of those chambers. We needed to have a more realistic, real world sort of situation where we had multiple trees. We wanted real intact forest communities. We didn’t want to have just a small number of trees inside of a chamber.”


The United States Department of Energy launched this experiment in Wisconsin’s northwoods seven years ago. Karnosky says they’re learning how the trees react to the higher CO2 levels, and that could shape the future of the world’s timber industry.


“Who will be the winners? Who will be the losers? Will aspen or birch or sugar maple? In northern Wisconsin here we’ve got probably 40 million acres of those species mixes. What’s going to happen under elevated CO2 in the next 100 years? Will these forests remain as they are?”


(sound of driving on gravel)


Driving to one of the experimental circles, we pull up to a ring of trees. Mark Kubiske is one of the two full-time on-site researchers.


“Now this particular ring is an elevated CO2 plot. CO2 is delivered through this copper pipe. It runs to that fan, there’s a large fan right on the end of that gray building.”


The scientists have found that trees in the CO2 circles grow 30 percent faster than trees without the gas.


“The trees are larger in diameter, they’re straight, they have lots of leaf area, they just look very healthy. That is just in tremendous contrast to the ozone ring. We’ll go up around the corner and look at one.”


Nearby another circle of trees is not doing nearly as well. The trees are skinny, twisted not as tall as the other sites. Higher ozone levels are hurting the trees.


At the sites where pipes emit both ozone and CO2, the tree growth seems normal – except for some stunted maple trees. The leaves of the aspen and birch take in much of the CO2, convert it to sugar which goes to its roots, eventually becoming a natural part of the soil. That suggests forests may help alleviate gases that cause global warming. The Project Director, David Karnosky says CO2 and ozone appear to cancel each other out. But he says it’s too early to draw any firm conclusions. Ultimately, he says governments will be able to look at this glimpse into the future and try to come up with emissions policies that help.


“The whole issue of the Kyoto protocol, our government not signing off on that. There’s been some relaxing of the feelings from what I’ve seen from the President’s report now that they’re beginning to realize that elevated CO2 is having an impact on global warming and could be impacting our plant communities.”


Karnosky says it’s possible that besides reducing emissions, governments might determine that planting more trees might be very helpful in reducing greenhouse gasses worldwide.


For the Great Lakes Radio Consortium, I’m Mike Simonson.

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Biologists Find Deer Devouring Rare Flowers

  • Largeflower bellwort (Uvularia grandiflora) is one of the wildflowers declining at many of the sites studied by University of Wisconsin researchers. (Photo courtesy of Dave Rogers, UW Herbarium)

Most of us think of the white-tailed deer as a graceful and cherished part of the natural scene. But it turns out when there are too many deer, it’s bad for some of the plants in the forest. New research suggests deer may be a prime culprit in a worrisome loss of rare plants in the woods. The Great Lakes Radio Consortium’s Stephanie Hemphill reports:

Transcript

Most of us think of the white-tailed deer as a graceful and cherished
part of the natural scene. But it turns out when there are too many
deer, it’s bad for some of the plants in the forest. New research
suggests deer may be a prime culprit in a worrisome loss of rare
plants in the woods. The Great Lakes Radio Consortium’s Stephanie
Hemphill reports:


Gardeners in many suburbs and rural areas know deer are good at
mowing down hosta, tulips and other favorite plants. In the woods,
deer munch on the small plants that live on the forest floor… plants
such as orchids, lilies, and other wildflowers.


Fifty years ago, researchers at the University of Wisconsin surveyed
hundreds of acres in the state, and made careful records of the plants
on those sites. In those days, the deer population was a lot lower
than it is now. In the last couple of years, two biologists went back to
many of those same sites and counted the plants living there now.


Tom Rooney says at most sites they found fewer different kinds of
plants.


“It tends to be the same species occurring over and again on the site.
You’re losing the rare species and picking up more and more
common species.”


He says they tried to link the decline in rare species to the fact that
the forest is getting older. But they found no evidence for that.
Instead, lead researcher Don Waller says the evidence points to
deer, which have increased dramatically over the last fifty years.


“The worst changes we’ve seen, ironically were in a couple of state
parks and a protected natural area, that showed losses of half or
more of species in 50 years. However, in these sites there was no
deer hunting, implying high densities of deer may be causing a lot of
the effects we see in the woods.”


Plants that rely on insects for pollination declined more than other
types of plants. Waller thinks it might be because the insect-
pollinated plants have showy flowers, which could catch the eye of a
wandering deer. As the flowering plants decline, the insects and
birds that rely on them for food could decline as well – bees, moths,
butterflies, and hummingbirds.


Waller says it’s worrisome because scientists don’t know how
particular insects and plants work together to support each other.


“As we’re losing parts of the ecosystem, we’re really not sure what
their full function is, they might play some crucial role we’re not aware
of and only too late might we become aware of the fact that this loss
led to an unraveling or threats to other species.”


Waller says the only places they studied that still have a healthy
diversity of plants are on Indian reservations. The Menominee Tribal
Forest in northeastern Wisconsin is pretty much like it used to be fifty
years ago.


(forest sounds under)


In this forest, there are only about ten deer per square mile. That’s
about as low as the deer population gets in Wisconsin. It’s not that
the tribe is hunting more deer; it’s the way the forest is grown.


Deer find lots to eat in young aspen woods; there’s less for them to
eat where pines and oaks and maples grow. Don Reiter is the wildlife
manager here. He says in the 360 square miles of the Menominee
forest, there’s really four different types of woods.


“We have pulpwood, we have northern hardwoods, white pine, red
pine, and again, the forest ecosystem as a whole, there’s plenty of
food out there for the deer.”


And because there aren’t too many deer, young pines and hemlocks
– and orchids and lilies – have a chance to grow.


In the upper Great Lakes states, wildlife officials have been trying to
thin the deer herd for several years. That’s because state officials
have been aware deer were causing problems by eating too many
plants. The recent study provides dramatic evidence.


In Minnesota, for instance, hunters are shooting four times the
number of deer they shot fifty years ago.


Steve Merchant is forest wildlife program consultant for the
Minnesota DNR. Merchant says the agency has liberalized its rules,
to encourage hunters to kill even more deer. But the number of
hunters hasn’t gone up in recent years. And lots of private
landowners post no-hunting signs.


“We need to have some help from people, people still need to get out
and hunt deer, and landowners need to provide that access for
people to harvest deer.”


Merchant says Minnesota is gradually trying to restore pine forests,
which were cut down for lumber and replaced with fast-growing
aspen. More pine forests could cut down on the deer population…


“But as long as we still have the strong demand for the aspen
markets that we do, and we manage those aspen forests in a
productive manner for wood fiber, we’re going to create a lot of good
white-tailed deer habitat.”


Merchant says it would take decades to change the woods enough to
reduce the deer population. And in the meantime, we’re losing more
and more of the rare flowers.


For the Great Lakes Radio Consortium, I’m Stephanie Hemphill.

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Forests for Lumber or Wildlife?

  • Loggers and environmentalists fight continually over the use of national forests. Managers at many national forests around the country are developing new long-range plans. (Photo by Stephanie Hemphill)

Loggers and environmentalists are in a continual fight over the use of national forests. One of their battlegrounds is the long-range planning process. Every ten to fifteen years, the U.S. Forest Service designs a new plan for each national forest. Right now, several forests in the Northwoods are getting new plans. The Forest Service says it’s paying more attention to biodiversity, and wants to encourage more old growth forests. Critics on the environmental side say the new plans are just business as usual. Loggers say they still can’t cut enough trees. The Great Lakes Radio Consortium’s Stephanie Hemphill reports:

Transcript

Loggers and environmentalists are in a continual fight over the use of
national forests. One of their battlegrounds is the long-range
planning process. Every ten to fifteen years, the U.S. Forest Service
designs a new plan for each national forest. Right now, several
forests in the Northwoods are getting new plans. The Forest Service
says it’s paying more attention to biodiversity, and wants to encourage
more old growth forests. Critics on the environmental side say the
new plans are just business as usual. Loggers say they still
can’t cut enough trees. The Great Lakes Radio Consortium’s Stephanie
Hemphill reports:


(sound of car door closing, footsteps in woods)


Jerry Birchem is a logger. He’s visiting one of his harvest sites on
land owned by St. Louis County, in northeastern Minnesota. The highest
quality wood will be turned into wooden dowels… other logs will go to a
lumber mill… the poorest quality will be turned into paper.


Birchem tries to get the highest possible value from each tree. He says in the last ten
years, the price of trees has tripled.


“We have to pay more for timber and the mills want to pay less, and we’re caught in the
middle of trying to survive in this business climate.”


Birchem likes buying timber from the county, like at this logging site. He hardly ever
cuts trees from the national forest anymore. He’d like to, but the Forest Service doesn’t
make much of its land available for logging. The agency says it doesn’t have enough staff
to do the environmental studies required before trees can be cut on federal land.


Jerry Birchem says loggers need the Forest Service to change that.


“You know there needs to be processes set in place so you know, it doesn’t take
so long to set up these timber sales. I mean, they’ve got to go through so
many analyses and so many appeals processes.”


Birchem says it should be harder for environmental groups to get in the way of timber
sales. But not everybody agrees with Birchem.


Clyde Hanson lives in Grand Marais, on the edge of Lake Superior. He’s an active
member of the Sierra Club.


He says it’s true loggers are taking less timber off federal lands in recent
years. But he says the Forest Service still isn’t protecting the truly special
places that deserve to be saved.


He says a place like Hog Creek should be designated a wilderness area, where no trees
can be cut.


(sound of creek, birds)


“Very unique mixture, we must be right at the transition between two types of forest.”


Red pine thrive here, along with jackpine and tamarack. It’s rough and swampy country,
far from roads. So far, loggers have left these trees alone.


But with the value of trees skyrocketing, Hanson says the place will be logged eventually.


Forest Service planners made note of the fact that the Hog Creek area is relatively
untouched by humans. They could have protected it, but they decided not to.


“And we think that’s a mistake, because this is our last chance to protect wilderness and
provide more wilderness for future generations. If we don’t do it now, eventually there’ll
be enough roads or enough logging going on in these places that by the next forest plan
it’ll be too late.”


But the Forest Service says it is moving to create more diversity in the
woods. It wants a forest more like what nature would produce if left
to her own devices.


The agency says it will reduce the amount of aspen in the forest. Aspen has been
encouraged, because it grows fast. When it’s cut, it grows back quickly, so loggers and
paper companies can make more money.


The trouble is, an aspen forest only offers habitat for some kinds of animals,
such as deer and grouse. Other animals, especially songbirds, need older trees to
live in.


So the Forest Service wants to create more variety in the woods, with more old trees than
there are now. But how to get the forest from here to there, is the problem.
Duane Lula is one of the Forest Service planners. He says fires and windstorms are nature’s way of producing
diverse forests. They sweep the woods periodically, killing big stands of older trees, and
preparing the soil for pines and other conifers. Jackpines, for instance, used to be more
common in the northwoods. Lula says the only practical way for man to mimic nature is
by cutting trees down.


“We can’t have those fires anymore just because people live here, there are private
homes here. There’s no way that we could replicate those fires. Timber management is one way of regenerating those jackpine stands in
lieu of having major fires.”


But Lula says the main purpose of timber cutting in the new plan is to move the forest
toward the diversity the agency wants, not to produce wood. And he says that shows the
Forest Service is looking at the woods in a new way.


“The previous plan tended to be very focused on how many acres you were going to
clearcut, how much timber you were going to produce, how much wildlife habitat you
were going to produce, and this one is trying to say, if we have this kind of desired
condition on the ground that we’re shooting for, then these other things will come from
that.”


As it does in the planning process in other national forests around the Great Lakes, the
Forest Service will adjust the plan after hearing from the public. Loggers,
environmentalists, and everyone else will have a chance to have their say. A final version
will be submitted to the Regional Forester in Milwaukee early next year. It could then
face a challenge in court.


For the Great Lakes Radio Consortium, I’m Stephanie Hemphill.

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Forest Plan Hits a Snag

In the early 1800’s, the forests of the upper Great Lakes were dominated by enormous white pines. By the close of the century, most of these white pine forests had been cleared by aggressive loggers with little or no experience in forest management. Other species of trees like aspen began to flourish in the spaces where the white pines once grew, and the forests of Michigan, Wisconsin and Minnesota were changed forever. Now, some environmental groups would like to see the forests returned to their natural state, and one group is taking the issue to court. The Great Lakes Radio Consortium’s Matt Shafer Powell has this report:

Transcript

In the early 1800’s, the forests of the upper Great Lakes were dominated by enormous white pines. By the close of the century, most of these white pine forests had been cleared by aggressive loggers with little or no experience in forest management. Other species of trees like aspen began to flourish in the spaces where the white pines once grew, and the forests of Michigan, Wisconsin and Minnesota were changed forever. Now, some environmental groups would like to see the forests returned to their natural state… and one group is taking the issue to court. The Great Lakes Radio Consortium’s Matt Shafer Powell has this report:

(Natural sound: walking through snow)

This patch
of land in Michigan’s Huron-Manistee National Forest was clear-cut last year. That means all the aspen trees were cut down, fed into a chipper, and hauled away to make particleboard and paper. All that was left was a wide-open field. A dense stubble of new growth is already emerging from the snow, though — a forest recreating itself. But here’s what bothers Marv Roberson, a forest policy specialist for the Sierra Club:
Nearly all of the new trees are aspens…

“You can see coming up, aspen that’s most of it less than a year old, some of it’s three feet tall already, and since it comes from root suckers, what it’s done is it’s gotten a head start on all the competition, so next summer when all these little trees have their leaves out, the floor of what used to be a forest and will be again, will have shade on it and so a lot of the smaller trees that want to come up from seeds that didn’t get a chance this summer won’t be able to.”

Aspens are known as
a “pioneer species.” Whenever there’s a major disturbance — a fire, a tornado, or clear-cut — aspens recover quickly. And they take over, squeezing out any other species that might try to grow there. Roberson says he doesn’t believe that would happen nearly as often if the forests weren’t clear-cut. He says the aspens would eventually grow old, die and fall down. And then, in the absence of a major disturbance, the white pines would thrive again.

It’s enough of an issue that the Sierra Club has filed a lawsuit against the United States Forest Service. The group is asking that the Forest Service do a study to analyze the long-term effects of clear-cutting aspen on federal land. In the meantime, they’re asking for a moratorium on aspen logging in certain parts of the national forests…

“The reason for our lawsuit is not to stop the harvesting of aspen. The reason for the lawsuit is to get the forest service to do an analysis of what the effects are. We’re right now going through the biggest forest experiment in North American history. We’re altering the kinds of forests that we have and we don’t know what the long term results are.”

The lawsuit has suddenly raised the stakes in what has been an on going discussion about the future of the national forests. Every ten to fifteen years, the Forest Service creates a new management plan for each National Forest in the Great Lakes region. The discussion often involves representatives from environmental organizations, wildlife preservation groups and timber companies. But it rarely ends up in court. Forest
Service officials are not allowed to comment on the specifics of the lawsuit. But Regional Planner Sam Emmons says any decisions on forest planning involve a lot of thought, foresight and input from the public…

“The Forest Service is looking for a diversity of timber species and diversity of wildlife habitats and understands that whatever transitions that are made have some effect on the local sawmills and pulp mills and the folks who live up in the North Woods.”

The forests are an important part of life in Minnesota, Wisconsin and Michigan. The federal government estimates that logging and forest-related activities annually contribute nearly 30 billion dollars to the economies of just those three states. For many of those who live in the region, logging is what pays the bills. Jim Schmierer of Michigan Technological University’s Forestry Program says residents in the Upper Great Lakes forests approach issues about the forests with a blend of intelligence, experience and passion…

“Maybe grandpa was a logger or they’ve been managing a family woodlot for fifty years and so there’s a real strong connection to the land in a lot of cases up here with people who that are very familiar with forest practices, so it’s kinda unique, a much different situation than some in the west, so definitely an interesting dynamic here.”

For that reason, the Sierra Club lawsuit has created some resentment among those who make their living from logging aspen. John Lamy is President of the Timber Producers Association of Michigan and Wisconsin. He says the Forest Service’s management plans involve a lot of public input and compromise. He says he doesn’t understand why the Sierra Club had to get the courts involved…

“I just feel that since everybody had a chance to participate in the plan and develop the plan and that plan has been approved that we should allow that process to go forward and the Sierra Club is choosing to go through the courts to change a major part of that plan.”

Marv Roberson of the Sierra Club says his group has been trying to work within the system. But he says the Forest Service isn’t getting the message. So the lawsuit is simply a last resort. In the end, the Sierra Club may be getting its way even without the lawsuit. Since the 1960’s the aspen population in the upper Great Lakes has actually declined. Roberson acknowledges this and offers this analogy: If a patient’s temperature goes from one hundred five degrees to one hundred three degrees, he might be getting better. But he’s still sick.

For the Great Lakes Radio Consortium, I’m Matt Shafer Powell.

Forest Service Sued Over Aspen Logging

The Sierra Club is suing the U.S. Forest Service to block logging of aspen in national forests in three Great Lakes states. The Great Lakes Radio Consortium’s Stephanie Hemphill reports:

Transcript

The Sierra Club is suing the U.S. Forest Service to block logging of aspen on national forests in three Great Lakes states. The Great Lakes Radio Consortium’s Stephanie Hemphill reports.


The lawsuit asks a federal court to force the Forest Service to stop cutting aspen on its land in Michigan, Wisconsin, and Minnesota. The Sierra Club’s Anne Woiwode says the Forest Service favors aspen production at the expense of a healthy forest, and a healthy economy.


“When they choose to keep aspen at very high levels, they choose not to bring back forests that may be of greater economic value, may actually produce many more jobs than aspen does for the amount of wood produced.”


Woiwode says clear cutting aspen prevents white pine and hardwood forests from growing back.


The Forest Service says it manages forests for a variety of types and ages of trees, and doesn’t try to encourage aspen where it would not grow naturally.


For the Great Lakes Radio Consortium, I’m Stephanie Hemphill in Duluth.