Growing Zones Warm Up

  • The National Arbor Day Foundation's revised hardiness zone map. (Photo courtesy of the National Arbor Day Foundation)

If you’ve been thinking about landscaping your yard, you should know things have
changed. The climate is warming so quickly that one organization has changed the
plant hardiness zone map. That’s the little map you sometimes see on the back of
seed packets. Lester Graham reports… you might want to check out the new map
before you spend hundreds of dollars on a tree that might not live long in your
warmer zone:

Transcript

If you’ve been thinking about landscaping your yard, you should know things have
changed. The climate is warming so quickly that one organization has changed the
plant hardiness zone map. That’s the little map you sometimes see on the back of
seed packets. Lester Graham reports… you might want to check out the new map
before you spend hundreds of dollars on a tree that might not live long in your
warmer zone:


You know, I’ve talked to a lot of gardeners and homeowners who do their own
landscaping about this plant hardiness zone map change, and at first they’re
kind of astounded. The growing zones are changing? Because it’s getting warmer?


But then, they sort of pause and think for a moment… and usually say something like,
“That makes sense.”


The United States Department of Agriculture issues the plant hardiness zone map.
It’s basically a map of the annual average low temperatures that helps folks figure
out what they can plant and expect to survive. But the USDA hasn’t updated its map
since 1990.


The spokesman at the National Arbor Day Foundation, Woody Nelson – I kid you not,
the Arbor Day guy’s name is Woody – Woody says his organization issued a new
map because it really needed to be updated:


“You know, people were asking us to help out, you know, ‘This old USDA map just doesn’t
seem to work for us anymore. I don’t think it’s accurate. What can you do to help?’
So we took it upon ourselves to give tree-planters the most up-to-date information
that we could.”


So the National Arbor Day Foundation looked at the low temperature data gathered
by the National Oceanic and Atmospheric Administration since 1990, and the people
were right: things are warming up:


“And over that 15-year span that we used, much of the country had warmed a full
hardiness zone.”


And there’s a ten degree difference from one zone to the next. It shows a real on-
the-ground trend.


Richard Andres is with Tantre Farm. They grow organic produce for farmers’
markets like this one in Michigan. Andres didn’t know about the new Arbor Day
Hardiness Zone map, but it makes sense to him. He says he’s seeing more
extremes:


“You know, last winter was unusually warm. The winter before, unusually warm.
So, we really didn’t even get a decent freeze. We had a huge amount of bugs the
following spring. So we are noticing more extremes.”


But a farmer or gardener can adjust things for annual plants. Long term, you’re
probably wondering whether you can now plant that dogwood or whether you
should plant that spruce from up north.


(Sound of sprinkler)


Phil Walsh sells a lot of trees at Lodi Farms nursery. He knew about the new Arbor
Day Hardiness Zone map. But, he says there’s a lot more to think about than just
the annual average low temperature when you’re thinking about planting:


“Cold is not the only, or really the most, important factor when determining plant
hardiness. Questions like soil: is it well-drained; is it not; is it wet; is it dry; is it acid
or is it alkaline; do you have wind; do you have shade? Questions like this: is it high
in organic material or low in organic material? These tend to have more impact on
whether or not plants survive than strictly the zone rating.”


Walsh says the trees are pretty tough, and most of them can adapt:


“Yes, things have warmed up over the last 15 years and they may well continue or it may change and it may go down. Pick a good, hardy plant that’s well-suited for your soil
and typically one that’s native here, that’s gone through these temperature changes
in the past and I don’t expect anybody’s going to have any problems with them.”


That’s not to say that every kind of tree is taking this in stride. For example, black
spruce trees adapted to Canadian and upper New England cold might not be such a
good choice as far south as it’s been grown in the past.


Woody Nelson at the National Arbor Day Foundation says trees native to the North
are starting to be affected by the warming climate:


“There’s a whole lot of white pines that have been planted in Georgia, in the South
as a nice landscape tree over the years. And now those white pines are coming
under a little bit of stress. The native lodge pole pines, the native loblolly pines in the
deep South, again native species are something that we want to promote and stick
with.”


So, the basic rule is: if the plant hardiness zone map has shifted one growing zone
warmer in just 15 years, you’ll probably want to stick to trees native to your area, or
from just a little south of you just in case this warming trend sticks around for a while.


For the Environment Report, this is Lester Graham.

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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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Repelling Christmas Tree Thieves

  • Landscape Manager Jeff Culbertson sprays a Scots pine with thief repellant containing fox urine. The smell isn't too noticeable outdoors... but when a thief drags a conifer indoors, the repellant heats up and makes for a memorable Christmas. Photo by Nanci Ann McIntosh, University of Nebraska-Lincoln.

Evergreen trees grace forests, campuses, and lawns around the region. Much to the dismay of landscapers and gardeners, some of those trees disappear this time of year, stolen by someone who may not quite get the idea of Christmas cheer. But some universities have found a way to fight tree rustlers. It involves a foul-smelling concoction that makes thieves regret taking a tree. The Great Lakes Radio Consortium’s Rebecca Williams has the recipe for this nasty, yet effective repellant:

Transcript

Evergreen trees grace forests, campuses, and lawns around the region. And much to the dismay of landscapers and gardeners, some of those trees disappear this time of year, stolen by someone who may not quite get the idea of Christmas cheer. But some universities have found a way to fight tree-rustlers. It involves a foul-smelling concoction that makes thieves regret taking a tree. The Great Lakes Radio Consortium’s Rebecca Williams has the recipe for this nasty, yet effective repellant:


About fifteen years ago, landscape managers at the University of Nebraska-Lincoln had a big problem. Tree thieves were cutting down the best conifers on campus. And the landscapers were getting calls from local residents, whose trees were also disappearing. Dennis Adams is a forester at the University of Nebraska.


“It’d be, you know, trees that have good Christmas tree form, so blue spruce, concolor fir, some of the pines – white pine, scotch pine.”


Some thieves were easy to track. Jeff Culbertson is a landscape manager at the university. He says students were stealing trees during Thanksgiving break… and they weren’t always perfect criminals…


“We’ve had instances where the students, I guess didn’t do a good job or didn’t think anybody cared, but you could find the dragged marks of the tree through the snow to their fraternity or dormitory or something like that so in those cases I think it was pretty easy for them to figure out where the tree went.”


Campus trees are worth hundreds of dollars, so the university was eager to find a solution. Dennis Adams discovered a solution… literally. He found the recipe in an old magazine… 1 part glycerine, 10 parts water, and 2 parts… fox urine.


Jeff Culbertson says the fox urine makes Christmas tree thieves think twice…


“It doesn’t really smell like skunk. Maybe like an extremely strong cat urine sort of smell. Or dog, something that’s very concentrated. But you know normally you’re not going to smell that. So it’s pretty pungent.”


Culbertson says since the University of Nebraska began spraying conifers in the 80s, they haven’t lost many trees. He sprays 50 to 100 Christmas-tree size evergreens each year. He used to wear a plastic spray suit, but now he just keeps the wind at his back.


“When I do the fox urine, I don’t have many volunteers that want to help me with that. So I take on upon myself to do it. They mostly stand away from me, and they probably don’t talk to me too much that day either.”


Culbertson says there is one problem with this technique… when it’s cold out, you don’t notice the smell. So he started adding a dye… he sprays blue or red stripes on the trees where he sprays the fox urine. He says it makes the trees that much less attractive, and serves as a warning. And each year, the university lets the local papers know they’re spraying fox urine again.


But if a thief still chops down a tree and drags it into his house … Culbertson says he won’t likely do it again.


“It would be a smell that you’d have a hard time getting rid of.”


Culbertson recommends the method to anyone with a lot of trees to protect. He says the repellant is pretty affordable, and normally wears off after the Christmas season. Most of the supplies, sometimes even fox urine, can be bought at a garden store.


“I use a small, 3 gallon bottle sprayer, typical sort of garden sprayer people would purchase at the hardware store, garden center… And I try to use hot water. The glycerin is very syrupy kind of like corn syrup. So it helps to loosen it up, heat it up and make it less thick. I mix it up, take it out, and just spray the trees by hand.”


Both Jeff Culbertson and Dennis Adams think thieves are just looking for a cheap tree. But Adams still finds the thefts a little unbelievable.


“I think people have to be pretty desperate to steal a tree for Christmas. That seems like it’s kind of in the anti-Christmas spirit to steal.” (Laughs)


Other campus managers, meanwhile…have cooked up their own people repellant. The University of Idaho adds a few ounces of skunk scent. It makes their mix even more memorable.


For the Great Lakes Radio Consortium, I’m Rebecca Williams.

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.