The Forestry Source - June 2017 - 9
Oak Restoration Underway in Illinois' Trail of Tears State Forest
By Andrea Watts
In the Trail of Tears State Forest, a combination of fire and thinning is promotes oak regeneration. A forest
inventory conducted by the Illinois Department of Natural Resources found a 50 percent decline of oak in the
overstory from 1980 to 2014. Photograph by David Allen.
ak is the predominant tree species
found in Illinois-the state boasts
20 native species, one of which is
the state tree-the white oak (Quercus alba).
A hardwood combination of oak-hickory is
the dominant forest cover type at 53 percent, yet in some parts of the state, oak species are on a noticeable decline. The Trail
of Tears State Forest, located in southwest
Illinois, is one area experiencing such a decline, and a multiyear research study is underway to determine which combination
and timing of the restoration methods of
prescribed fire, mid-canopy thinning, and
logging creates the best conditions for oak
regeneration. The long-term goal is that the
lessons learned here can be applied elsewhere in the state.
"Oak still dominates most of our forest, but like Trail of Tears, the trends are
very, very clear. In most woods, we have
very little oak regeneration," explained David Allen, a district forester with the Illinois
Department of Natural Resources (DNR)
and an SAF member.
The 5,114-acre Trail of Tears State
Forest was established in 1929 and has
an extensive history of active management
dating back to the Native Americans and
continuing with European settlement; the
area has been grazed and logged. In recent
years, active management lessened due to
DNR's budget issues and the public being
unsupportive of timber harvesting.
However, four years ago it was recognized that active management was needed
to retain oaks in the Trail of Tears' overstory. A forest inventory conducted by DNR
found a 50 percent decline in overstory
oaks from 1980 to 2014; currently, one in
five overstory trees are oak. Of the saplings
inventoried, one percent were oaks, with
other hardwoods, such as maple, beech,
and ironwood, regenerating more successfully.
Allen described the Trail of Tears' oak
regeneration project as resulting from a
convergence of interests.
"Trail of Tears is a large forest block
in the Illinois Ozarks and is a featured site
of the forest and woodlands campaign of
the Illinois Wildlife Action Plan," he said.
"So there was an interest from a wildlife
standpoint, and since it's also a state forest,
it's important for the Illinois Forest Action
Another driver for moving forward
with the project was that many of the oak
trees, which would serve as seed sources,
were nearing the end of their life span.
Allen said that there was concern that if
action were delayed, the window of opportunity would be lost, particularly for
the red oak and black oak. Based upon
past management activities, it's estimated
that many of the trees were established between 1850 and 1930.
Recognizing that the regeneration
method of harvesting could prove contentious-20 years ago, there were protests
against the harvesting at Trail of Tears-
DNR set about to create a collaborative
group of agency scientists, researchers
from academia, and representatives from
nonprofit groups, including The Nature
Conservancy and the local chapter of the
Sierra Club, to provide advice and comment about the project design.
"The reason we felt we needed an
in-depth plan and a fairly comprehensive
process was harvesting timber, in particular, on public lands in Illinois has a history of controversy," Allen explained. "We
wanted to bring together a diverse group
of people who had an interest in forest
management in general but also specifically at Trail of Tears."
SAF member Benjamin Snyder, also
a district forester with DNR, credits the
agency's focus on ecosystem management
and oak regeneration in gaining support
for the project.
"[For the project] we didn't just look
at trees. We looked at how we're going to
affect wildlife and habitat and understory
plants in the oak-forest community, to help
people understand that we're focusing on
all aspects of the ecosystem," Snyder said.
Fortunately, the group quickly recognized what was at stake and what regeneration methods would prove most effective. "We all agreed that we needed fire.
We all agreed we needed some form of
cutting, because fire just wasn't going to
be enough," Allen said. "That was the hurdle-we didn't know if everyone would
agree on the need for cutting, but there
was 90 percent agreement."
The first overstory harvest in the Trial of Tears State Forest, which began in fall 2016 and finished in February
2017, received little complaint, largely because of efforts to educate the public about the necessity for a
harvest. Photograph by Benjamin Snyder.
The reason that fire alone wouldn't
be enough, he explained, is because of the
dense mid-canopy of the six- to ten-inch
dbh maple and beech; a fire hot enough to
take out this mid-canopy would likely also
damage the overstory trees. However, fire
can remove trees of less than five inches
dbh while still leaving the canopy intact.
"Prescribed fire really needed to be part
of the management of the forest," Snyder
said. "Otherwise, we're going to see continued mesofication and conversion from
oak-hickory to beech-maple.... In the Illinois Ozarks, we have deep loess soil, so
it's a very productive area, and without fire
the mesophytic trees really take over."
Within the state forest, 925 acres were
set aside for a demonstration area: one
portion serves as a control, one portion
will only be burned, and another portion
will be cut and burned. Within the latter
section, Allen and Snyder are also testing
whether a mid-canopy stand-improvement
cut will result in better regeneration compared to an overstory or shelterwood harvest followed by a stand-improvement cut.
Snyder said that the demonstration area
would determine the best management actions and their sequence. "The work that
we're doing is based on the research, and
it's pretty clear what we have to do; however, the combination of management and
the sequence of it are the questions for this
specific site," he said.
Last fall, the first cutting took place in
the overstory harvest section and was finished in February. The goal for this section
is to reduce the total basal area by 40 percent through the combination of overstory
harvest and a stand-improvement cut, resulting in a residual density of 70 square
feet per acre. The remaining oaks are those
with the healthiest crowns.
This spring, project personnel conducted a second burn in the burn-only
section, and Southern Illinois University's
student-led Fire Dawgs crew did much of
the work. Snyder said they expect to burn
about three times over the course of the
next 10 years.
Because of the collaborative nature of
the project and the effort made to host a
media day when conducting the overstory harvest, which resulted in several news
articles and TV segments, Snyder said that
the majority of the public has been supportive of the project. "We tried to really
get the word out there on why we're doing
it.... I think because of that we had a lot of
support and no opposition."
And although Allen said that they
have converted some opponents to skeptics who are taking a wait-see approach to
the project, outreach will still be needed
when future harvests are planned. "We're
not yet to the point where we can say we're
just going to routinely harvest timber every
year or two," he explained. "I don't think
we're quite there yet [because logging is]
still potentially contentious."
With the demonstration area open
to the public and signage in place to explain the project, the public can also see
firsthand how the forest is responding to
the different active-management practices. Snyder sees the demonstration area as
a useful tool not only for other naturalresources professionals looking at oak
regeneration on public land, but also for
private landowners who are apprehensive
about undertaking similar work because
they are uncertain what the end result will
"The real benefit [of the demonstration area] will be an outreach tool for people in the region and beyond the region
to see how this process works and what it
looks like and the best sequence to regenerate oaks," Snyder said.
As part of the oak regeneration study,
research plots are key to monitoring the response of understory plants; bird surveys
will also be conducted. As for the wildlife
focus, "we hope to improve some of the
bird species that use young forests or need
an open canopy," he added.
Although there isn't a definite end
date for the project, Snyder is hopeful that
noticeable differences will be evident in 10
years, and the goal is to use the results at
a landscape scale across the Illinois Ozarks
and Shawnee National Forest, since they
too are facing similar oak regeneration
"Hopefully, we'll be doing similar type
of work at other state sites, especially fish
and wildlife areas and state forests across
Illinois," he said.