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Citizen Science at Site
61
By
Joe Neumann
I began with sixty-seven purposeful
paces to the east along Ninety-fifth Street. Now, with
a compass, I orient myself due south and count off 241
paces straight into the woods. My assistant for the day,
Lissette, hands me a square frame of white plastic piping.
It is about twenty inches across, enclosing a quarter
square meter. I place it precisely at the tip of my shoe,
on the random bit of forest floor before me. A man riding
a horse on a nearby trail asks what we are doing. I tell
him: "an official plant survey." I wonder if
he thinks this is something occult.
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Call it a "land audit" or
a "rapid assessment." We are seeking snapshots
of the state of nature in the Forest Preserve District
of Cook County. Lissette and I are surveying "site
61" in the Cranberry
Slough Nature Preserve in the Palos area, part of
a study organized by the Friends
of the Forest Preserves. We have been provided with
an aerial photo and instructions for finding our starting
point. These also give us the randomly chosen direction
in which we should proceed in this case, southeast.
I place the quarter-meter quadrat
frame on the ground every ten meters (thirty-three feet),
and Lissette and I record all the plants in the quadrat
frame, taking twenty such samplings in this same line.
At every third stop, we divide the woods around us into
quarters and record the nearest full-sized tree and the
nearest sapling in each quarter left front, right
front, right rear and left rear. Foresters call this the
"point quarter" method. It will give us a random
sample of the trees.
Our first sampling does not look promising.
The ground is so heavily shaded that little grows. There
are only two stunted plants here, one being poison ivy.
Our initial survey of the trees suggests a trend: all
the old trees are oaks, while black cherries dominate
the saplings. The overall study showed similar results.
The white oak was the most abundant mature tree recorded,
while the black cherry ranked thirteenth. For saplings,
however, the black cherry was number two (behind only
the invasive European buckthorn), while the white oak
ranked fifteenth.
To peer into the woods of the past,
examine the mature trees. To peer into the near future,
examine the saplings. To peer into the far future, examine
the seedlings. There are no oak seedlings in the twenty
data sets we record. I don't see any during our walk.
When I was doing another sampling at a nearby site, my
assistant found a stash of oak seedlings inside a thorny
Japanese barberry bush where the deer, which often dine
on the woody sprouts, couldn't get them.
We enter an area where there is more
light. The plants respond with a flush of green. Lissette
cradles the slender stalk of a white grass. "Grasses
are so peaceful," she says. I tell her to be careful
if she runs her hand the wrong way along the stalk,
it will slit her skin. Nature is about survival, not serenity.
I point out to Lissette how cherries
are overwhelming the oaks. I explain fire's role and the
need for controlled burns. I tell her that the district's
ecological restoration volunteers, like me, thin cherry
and buckthorn saplings. Is it good for the woods if cherries
replace oaks? Is it good if deer become so populous that
the oaks cannot reproduce? Studies like this one give
scientists and citizens the tools to address these questions
and, in this case, to identify a problem.
The Friends of the Forest Preserves
study (conducted with the help of the Sierra Club, Audubon-Chicago
Region and Friends of the Parks) found that 68 percent
of the Cook County forest preserve lands set aside for
conservation (as opposed to infrastructure and recreation)
are in poor condition. Sadly, the damaged area that Lissette
and I surveyed had the second highest number of quality
native species of the eighty-seven areas examined. Our
forest preserves need help.
Check out the entire study under "Programs"
at http://www.fotp.org/programs/Forest%20Preserve.asp.
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