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On the hunt for first flower of spring
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The weather last Wednesday morning was hostile. The air temperature had sunk to 16 degrees overnight, and the wind was blowing from the northwest at 15 miles an hour. What a day to go looking for wildflowers. But that’s exactly what I did.
See, if you wait until April, when showy beauties like Virginia bluebells carpet the woodland floor, you’ve missed the emergence of spring’s first wildflowers by more than a month already.
Thanks to guidance from Rick Larimore, who is a wetland plant ecologist with the Illinois Natural History Survey, I found my quarry at the Middle Fork State Fish and Wildlife Area, north of Kickapoo State Park in Vermilion County. It was growing thickly in a large swath along the base of a hill, where water from the adjoining upland seeps to the surface and keeps the ground saturated through much of the year.
I have to admit that the flower of the plant in question, which goes by the scientific name Symplocarpus foetidus, is not attractive in conventional terms. It’s a small, spongy, egg-shaped affair that grows up hidden within a specialized leaf that forms a hood around it, in botanical terms, a “spathe.”
Unlike the flower it contains, however, this spathe is a work of art. Bulbous at the base, which you could encircle with your thumb and index finger, it extends upward in a twisting, tapering spiral three to six inches tall. In color, this spathe may be as nondescript as the winter ground from which it grows, dullest brown or gray. But it may also be quite dramatic. Some I saw were wine-red, marked with lighter shades the color of brick and speckles of pink.
Aside from the beauty of its spathe, Symplocarpus foetidus distinguishes itself from all other plants native to Illinois by the fact that it generates heat--enough so that its flower can remain 36 degrees F warmer than the surrounding air for a period of about two weeks. This capacity allows it to grow in frozen soil, and also provides an inducement for early emerging insects, by which it is pollinated, to hang around.
[ Photo, top, by author. Thermal image created by Paul Nabity, U of I Institute for Genomic Biology.]
I’ve been coy about calling Symplocarpus foetidus by its common name because to do so is to draw attention to aspects of its personality that people may find unappealing. That’s “skunk cabbage,” and this is definitely a plant that lives down to its name.
As the flower of skunk cabbage matures it gives off a distinct, skunk-like odor, an odor that can also be produced by crushing any part of the plant. That’s unattractive to people, but a turn-on for carrion-eating insects, and, hey, a plant needs to please its pollinators.
Something cool about skunk cabbage that you can’t know by observing its above-ground components is that it grows deeper into the earth every year, pulled downward by a massive root system that alternately extends and then gradually contracts. On account of that, it is said to be impossible to dig an old one out of the ground.
If you are not inclined to seek out the wet areas where skunk cabbage grows in the next few weeks, you might look for it later in the season as its giant leaves unfurl, some to lengths of more than two feet. But don’t wait too long. As summer begins to wear, the leaves of skunk cabbage die back in their own unpleasant way, dissolving into a smelly black slime rather than drying out.
Pesticides save the day! or not. Insect Fear Film Festival has it both ways
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In anticipation of the 31st
Annual Insect Fear Film Festival, which they will host Saturday on the UI
campus, this week’s Environmental Almanac is written by two members of the
Entomology Graduate Student Association: Michelle Duennes and Todd Johnson.
The theme of this year’s Insect Fear
Film Festival is “PESTICIDE FEAR!” In one of our two feature films, "Riders
of the Whistling Pines," Dichlorodiphenyltrichloroethane (aka
DDT) plays a prominent role. As the story opens, an outbreak of tussock
moths is threatening the health of the trees in the North Woods. Government
foresters want to spray DDT to eliminate the pests and keep the forest healthy.
Here’s the plot twist—a bunch of greedy loggers want the trees to be damaged, so they can cut and sell the wood.
Enter the singing cowboy Gene Autry wearing a white hat. Exciting action
follows, but we won’t spoil the plot for you.
Whereas 65 years ago, pesticides were
portrayed as heroes, today you would be hard-pressed to find anything in praise of them. As
entomologists, we’re concerned about the health of insects but we also
recognize that pesticides can be really useful. Without them, many farmers
simply would not be able to grow or sell crops damaged by insect pests. Take
California, for example, where almonds are king. Over half-a-million acres of
orchards contribute approximately 80 percent of worldwide almond production. A
pest of almonds is the navel orangeworm. During its immature stage, the
caterpillar feeds on the developing almond. Without effective control measures,
this insect could severely damage the 4.3 billion dollar industry.
That’s where pesticides like the
pyrethroids come into play. Pyrethroids act on the nervous system of an insect,
causing paralysis and death, and they’re very effective against navel
orangeworms. There is a catch, though--pesticides are great at what they do,
but they should not be the major focus of an insect pest management program. (Entomologists
generally favor a system known as Integrated Pest Management, or IPM, which uses
chemical, biological, and cultural controls synergistically to control pests
and reduce inputs of pesticides into the environment.)
The problem with pyrethroids is that they aren’t very specific. In addition to
killing the navel orangeworm, they also kill the honey bee pollinators of the
crop, as well as beneficial predatory mites. Growers are now advised to not
apply these pesticides right before or during flower bloom and avoid their use
if possible.
Our second feature film emphasizes (in
a sensationalized and exaggerated fashion) the tradeoffs to pesticide
application. “Locusts: The 8th Plague” is a 2005 Syfy original about a swarm of
genetically engineered, flesh-eating locusts. When the locusts escape from a
government research facility in Idaho, the military wants to eradicate them
with chemical weapons. Colt Denton, local entomologist, also wants to save the
local human population. But instead of chemical weapons, he proposes using
“organic pesticides.” Here, the movie mixes things up a bit. The characters use
“organic” to mean non-toxic and safe for the environment. In reality, the term
“organic insecticides” as used today refers to insecticides that are not
synthesized in a laboratory. (In the 1940s and 1950s, “organic insecticide”
meant any pesticide synthesized in the laboratory that did not contain heavy
metals such as copper and arsenic—those insecticides were called “inorganic.”)
An example of an “organic” pesticide
would be nicotine, a familiar toxin from tobacco plants that acts on the
nervous systems of animals and can be very deadly at low doses. Synthetic
analogues of nicotine, the neonicotinoids, have recently gained infamy because
of their potential effects on honey bees; a severe mishap with a pesticide
applied inappropriately in Oregon caused the mass
death of over 50,000 bumble bees.
To reduce their negative effects of
pesticides, it’s important to understand the biology of the target insect(s)
and how they will affect the environmental as a whole. Additionally, pesticides
should be used only when necessary, and in conjunction with other management
tools. We hope you learned a little bit about pesticides and will join us as we
suspend our disbelief (briefly) and enjoy some great pesticide fear-related
movies.
Doors to Foellinger Auditorium open at
6pm with an insect petting zoo, face-painting, BugScope, art contest display,
and our first ever “Pesticide Petting Zoo.” An introduction by Entomology Department
chair, May Berenbaum, will be given at 7:00 and the films start at 7:30.
On the Web:
All invited to participate in U of I Scholarship of Sustainability series
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To engage in the work of conservation can be inspiring and
uplifting, especially when the stakes are clear, the issues are close to home
and people come together. Witness the formation of the 5th and Hill Neighborhood Rights campaign, which arose after the discovery of soil
contamination in a Champaign neighborhood, and Stand Up to Coal, which is
organizing the effort to stop a coal mine on the border of Champaign and
Vermilion Counties. Or look at the opposition that’s formed to prevent the
Clinton Landfill from accepting PCBs; everyone from local citizens to U.S.
senators and the entire range of state and local officials has taken up the
banner for protecting the Mahomet Aquifer.
But the work of conservation can also be downright
depressing. There seems to be no end of schemes that put private profits ahead
of public goods. Who would have thought we’d be fighting to keep the
Urbana-Champaign Sanitary District from selling water that supports the life of
our streams to a Tuscola fertilizer factory?
[ Salt Fork of the Vermilion River, currently threatened by reduced flows from UCSD and pollution by a proposed coal mine. Photo by author.]
And this isn’t even to mention mega challenges like
biodiversity loss and climate change. Maybe to make conservation more effective
we need to rethink our approach from the beginning.
Eric Freyfogle thinks so. He’s a U of I professor of law who
writes extensively about conservation—from a legal perspective, of course, but
also with attention to the cultural and economic underpinnings of our current
environmental plight. Among his books on the subject are titles including Justice and the Earth and Why Conservation is Failing and How It Can
Regain Ground.
Beyond contributing to discussion of these topics among like-minded
scholars, Freyfogle also seeks to call attention to them across the U of I
campus community, as well as among people from the wider world who are
interested in the same questions—and he thinks everyone should be.
Toward that end, he and collaborators Robert McKim, a professor
of religious studies, and yours truly, in my role as a lecturer with the School
of Earth, Society and Environment, coordinate an annual series of talks each
Spring under the title, “ The Scholarship of Sustainability.”
The series, which is sponsored in part by Institute for
Sustainability, Energy and Environment, is meant to counter the specialization
that characterizes work within disciplines on campus. And it opens up broad
questions, such as “How should we be living?” and “What would the world look
like if we were living well—that is, if conservation won?”
Many of the speakers in the series teach at the UI, and professor
Freyfogle himself will address one of the more provocative questions of the
series, whether capitalism is fundamentally incompatible with conservation. Other
speakers will be visiting campus. Dale Jamieson, a professor of environmental
studies and philosophy at New York University address the ethics of relationships
between people and other forms of life. His March 6th talk, "Grass Fed Environmentalism: Living Responsibly in the Anthropocene," will also be part of Ethics Awareness Week on campus, an initiative of the National Center for Professional and Research
Ethics here.
[Self promotion alert: I'll be speaking as part of the series myself on March 20th; my talk, "Seeing and Valuing the Natural World," will feature many photographs of east central Illinois wildlife.]
This year’s Scholarship of Sustainability series begins today,
so you’ll be hearing this plug too late for the first session. But it runs Thursday
afternoons from 4:00 p.m. until 5:30 through April 17 (skipping the week of
spring break). Talks are held in Room 149 of the National Soybean Research
Center, 1101 West Peabody Drive, Urbana. Further details about the Scholarship
of Sustainability Series are available on the homepage of the School of Earth,
Society and Environment http://www.earth.illinois.edu/students/courses/sos.html.
We're not alone coping with the cold
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If you’re like most Midwesterners, you’ve had about
enough of winter by now. And it probably does nothing to brighten your day for
me to point out that Punxsutawney Phil saw his shadow on Sunday. So let’s leave
that prognosticating groundhog behind, and contemplate some of the fascinating
wintering strategies of other furry creatures.
I learned about these through a recent
conversation with Joe Merritt, who is a mammal ecologist with the Illinois
Natural History Survey (at the U of I Prairie Research Institute). Over the course of a forty-year career, Merritt
has specialized in exploring how mammals cope with winter. Among other
projects, he has studied shrews under the snow in Siberia, pikas in the
mountains of Tibet and the variety of small mammals that inhabit the Rocky
Mountains of Colorado.
Take
hibernation, for example. If asked to name an animal that hibernates, many
people would say bears. As it turns out, though, bears do not hibernate—at
least according to the definition scientists use. Yes, they retreat to a den for
months on end, and during that time don’t eat, drink, urinate or defecate. In
addition, their metabolism is suppressed and their heart rate slows. But—and
this is a big “but” for mammalogists—the body temperature of bears in winter
remains somewhere in upper 50 degree range. So Merritt et al. would say bears
undergo a period of “winter lethargy.”
[An Arctic ground squirrel takes a peek from its burrow. Photo by Øivind Tøien.]
In
contrast, the body temperature of most “true hibernators” drops all the way
into the 30s. And at least one, Merritt pointed out, can survive with its body
temperature below freezing. The coldest core temperature recorded for a hibernating
arctic ground squirrel—a relative of the thirteen-lined ground squirrel common
in Illinois—was less than 27 degrees!
Hibernation
is also a more complex phenomenon than you might expect. Using using radio
telemetry, scientists have been able to monitor fluctuations in the body
temperature of hibernating animals. In doing so, they’ve found these critters
experience regular episodes of arousal, during which their body temperature rises
from its cool baseline all the way up to normal.
These
spikes are very costly to the animals—that is, they use up a great deal of
energy—which suggests there must be good reasons for them. But nobody yet fully
understands exactly what those reasons are. One reason seems to be that warming
up enables animals to experience REM sleep, which is necessary to maintain
brain function over time.
While
hibernation is fascinating, it’s actually a fairly uncommon way for mammals to
cope with winter. Of the 60 mammal species native to Illinois, only 16
hibernate, and 12 of those are bats.
How do the rest get by? Body mass is important, since it
enables bigger animals to store energy--and “bigger” here starts with tree
squirrels, raccoons and opossums. Insulation helps, too—a nice layer of
subcutaneous fat and a fur coat. Shivering generates heat when circumstances
demand it. And hanging out with friends.
In a recent study of least shrews, which range form Central
America to Wisconsin, Merritt found that the cold related energy needs of
individuals were reduced by nearly half when they packed into communal nests.
Maybe the question there is how they get along well enough
to stay in such tight quarters. I know some mammals who are getting cranky from
being cooped up this winter.
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