History of the Preserve's
Mesic Prairie Reconstruction Project
In 2001, approximately 68 acres
of former cornfield and Eurasian meadow were prepared and planted with a seed
mix that contained 22 native grasses, forbs and legumes. To simulate a pre-settlement
oak savanna, 40 Bur
Oaks (Quercus macrocarpa) and 2 Shagbark
Hickories (Carya ovata) were rescued from construction sites and transplanted
in parts of the prairie. For a list and description of the plants included
in the seed mix click
here.
Why
Do We Burn the Prairie?
The Asylum Lake Preserve, including
the prairie/savanna reconstruction project, is an isolated remnant of what
once was a much larger landscape that was maintained by fire, grazing and
other natural disturbances. Fire is one of the more useful interventions.
Prescribed fire is used as a management tool, not only for its historically
good track record, but also because of its low relative cost when compared
to mowing, herbicides and chainsaw work. It's important to remember that the
plants of the tallgrass prairie did not simply adapt to growing with fire,
they evolved with fire over the course of tens of thousands of years.
Consider the Following
Benefits of Prescribed Fire:
What
is Prescribed Fire?
Before prescribed fire is used
at Asylum Lake Preserve, a document known as a "burn prescription"
is prepared. The document identifies the acceptable conditions under which
a burn will take place. Some of these conditions include expected fire intensity,
relative humidity, wind speed and direction, air temperature and fuel moisture.
Also contained in the burn prescription is a plan for how the fire will be
ignited and contained.
It is difficult to predict good
burn weather more than a few hours ahead of time. If any of the conditions
identified in the burn prescription is unacceptable or "out of prescription",
the burn is postponed.
WMU's
1st Prescribed Burn:
After allowing a full growing season
for the plantings in 2002, it was time to plan a burn. In the spring of 2003,
a trained and experienced burn crew was hired by the University to conduct
the first prescribed burn on the prairie reconstruction. Assisting the 'Burn
Boss' and his crew were staff members from Landscape
Services. Fire crews from both the Oshtemo
and Kalamazoo Fire Departments were on hand in case they were needed.
On April 24, 2003 our Burn Boss,
Jim Bruce, decided that conditions in the burn prescription were satisfied.
Wind speed was 6-8 mph from the SSW and would keep smoke from blowing over
Drake Road. Air temperature and relative humidity were predicted to be such
that smoke would rise aloft rather than blowing closer to the ground. Fuel
moisture was excellent, but the problem we experienced was a lack of fuel.
In all but two of the burn units, there was simply insufficient vegetation
to carry a fire.
This, however, was not the case
with burn units 2 and 3, the Switchgrass
(Panicum virgatum) plots immediately south of Cherry Lane. Here the dry grasses
waved 6' in the air and promised a spectacular burn.
Trees within the burn units were
first protected by spot-firing around them. A "black line" of burned
vegetation was formed by back-firing the lee side of the grasses. Finally,
the head-fires were ignited which raced across the plots, meeting the back-fires
in the middle. Standing in a safe location up-wind, the roar of the headfire
was so loud that several of us simply put down our tools to enjoy the spectacle.
When
Will the Next Burn Take Place?
The next burn has yet to be determined.
The prairie has been divided into burn units and as of the spring of 2007,
each of the units has been burned at least once. During the summer of 2008,
a floristic inventory will be performed on the property. Based on the results
of this inventory, we will be able to create an effective burn schedule. Once
the conservative prairie plants are firmly established and weeds are under
control we will limit burns to only 1 or 2 burn units each year. This will
provide refuges for insects, birds and myriad other forms of wildlife. The
goal of fire management at Asylum Lake Preserve is to establish a biologically
diverse habitat and increase the educational and aesthetic experience for
visitors.
Fire Management Documents:
1. Fire
Management Justification for the Asylum Lake Preserve Prairie and Oak Savanna
2. Fire
Regime Proposal for the Asylum Lake Preserve
3. Monitoring
at the Asylum Lake Preserve: Prairie and Oak Savanna
4. Site
Fire Management Goals for the Asylum Lake Preserve
Related Links:
1. Michigan
Prescribed Fire Council
2. The
Nature Conservancy - Fire Management
3. The
Northern Prairie Wildlife Research Center
4. Society
for Ecological Restoration International
