|
Arundo donax is
a nasty, ornery plant likely first introduced to the United States
from the Middle East in the early 1800s. Often known as giant reed,
its fleshy, fibrous roots penetrate deeply into the soil. The plants
grow thick and fast and as high as 20 ft. Though it has some redeeming
qualities, such as being used for erosion control in the Southwest
or for making reed instruments, in many places it is also a bane
to the environment. Giant reed can choke stream channels, crowd
out native plants, interfere with flood control, increase fire potential,
and reduce habitat for wildlife.
Such was the case in
Santa Clara, CA, where a nature reserve and natural waterway had
been overrun by the stuff. More than 4 ac. clogged the land, killing
natural plant species and diverting the waterway from its natural
course. In fact, even though a small fire burned much of it to the
ground in August 2001, it grew back entirely within a month.
 |
| Preconstruction
Arundo donax stand |
For a solution, the Santa
Clara Valley Transportation Authority turned to Aquatic Environments
Inc., an aquatic remediation and construction firm based in Alamo,
CA.
"It was a bit of
a departure from what we typically do in terms of remediation and
construction," states George Forni, owner of Aquatic Environments.
"However, it was a job that required our advanced equipment
and specialized techniques."
By concentrating on the
growing demand for environmentally sensitive construction, Forni's
firm has grown from $25,000 in revenue to more than $2.2 million
in just a few years.
"We formed this
company in response to a market void created by increasing environmental
concern and regulation," he explains. "We still do the
same heavy-duty excavation and construction of a normal firm, but
we're able to do it with little to no environmental impact. As a
result, we are able to work efficiently on jobs where regulations
have otherwise restricted equipment."
 |
| The
JackBucket on this loader is able to sift out excess soil, leaving
the root ball and plant for offhaul. |
 |
| Hand
crews remove giant reed from areas too remote for equipment. |
In Santa Clara, as elsewhere,
giant reed would be extremely difficult to remove by hand, requiring
laborers to cut off the bottom of the weed and then apply poison
to the root system. The technique is difficult, slow, and effective
only 60% of the time. By contrast, when the entire root system is
excavated with machinery, the process is 98% effective. And yet,
prior to Aquatic Environments's arrival, regulations called for
much of the work to be conducted with hand labor to avoid causing
environmental damage within the natural area. "The job would
have been very difficult for someone using conventional techniques,"
remarks Forni.
Instead, Aquatic Environments
arrived on the site with the Posi-Track 2800 from ASV, a Caterpillar
affiliate, in tandem with a Caterpillar 277 or is it 267? Multi
Terrain Loader. Both utilize ASV's patent-pending Maximum Traction
and Support System undercarriage, which gives the machines high
traction and extremely low ground pressure (2.5 psi compared to
the 50 psi of a traditional wheeled skid-steer). With this advanced
technology, Aquatic Environments could maneuver throughout the region
with sensitivity to the environment while also powerfully removing
the difficult plant.
"To be both powerful
and gentle at the same time is a unique attribute and is one of
the reasons why we're growing so quickly," notes Forni. His
techniques, it turned out, were so environmentally sound that the
Santa Clara Valley Transportation Authority changed the specifications
on the job when it saw what Aquatic Environments could do.
"Once the mechanical
removal process had begun, the regulatory agencies were so impressed
with the lack of overall disturbance to the sensitive site that
they opted to convert areas previously designated as requiring hand
labor to mechanical," recalls Forni. "This saved an enormous
amount of time and resources."
 |
| Site
cleared of giant reed |
The project began with
a thorough inspection of the region on foot. Because the giant reed
had taken over so much of the area, it was difficult to know where
the streambanks began as well as the location of other obstacles.
"We had to inspect
it because the plants were so thick that it would have been easy
for a machine to run over a 10-foot drop-off and never see it,"
Forni says.
Once the inspection was
complete, the excavation began. With a bucket that allowed dirt
to sift back to the ground, the rubber-track loaders began to remove
the plants. After digging out a large root system, the machines
loaded the reed into a Marooka, a rubber-track transport that hauled
the material to a chipper for processing.
Meanwhile, once an area
had been cleared of giant reed, the Posi-Track and Multi Terrain
Loader graded the area back to a natural contour. It was then hydroseeded
with native plants and surrounded by biodegradable erosion control
rolls.
In addition to removing
the giant reed from the land, Aquatic Environments also used miniexcavators
at the stream edge to remove the root mass and return it to its
normal course. "The resident biologist on the job commented
that the means of removal was similar to a surgical procedure,"
relates Forni. "Because of the specification changes, we finished
the job 45 days faster than we thought we could before those regulations
were lifted."
Though Forni says most
contractors will never have to worry about giant reed on a job site,
most will continue to be impacted with increasing environmental
regulations and restrictions. "I don't think it's any secret
why we've had success. We are constantly searching for options and
solutions to environmental regulations. While much of our competition
continues to struggle with such new laws, we've chosen to find solutions."
Guest author Jay Lemke
is a writer based in Minneapolis, MN.
|
