8
THE DAVEY BULLETIN
|
March/April 2018
TEACHING SAFETY
AT THE IAA CONFERENCE
Don Roppolo, manager of arboricultural training, Davey
Institute, gave a two-day presentation at the Illinois Arborist
Association Annual Conference and Trade Show focusing
on safety, as it relates to several topics including aerial
rescue, chainsaw felling techniques and forces in rigging
and climbing.
Roppolo said many people don't fully understand how
much force is generated, with a small amount of weight,
while climbing or rigging. As an example, a piece of wood
weighing 50 pounds can potentially have a force of 500
pounds depending on how it's rigged or allowed to fall.
During his presentation, Roppolo emphasized how knowing
the force being generated by climbing or rigging is important,
so a climber knows whether the rope or branch union will
support that force. It's especially important when dealing
with aerial rescues.
"Say I was to slip, all that force goes into that anchor point,"
he said. "If that force I generate goes into that branch union,
will it support that force? If the answer is no, then you need
to put that rope through a different branch union that will
support the potential load."
Davey's Don Roppolo demonstrated what would happen if you release
yourself without adjusting your climbing system. With his gear, he was
about 210 pounds not moving. Once he pulled himself up one arm's
length and released, the force exerted while dropping the length of
one arm's pull was about 900 pounds.
FIELD NOTES
MATURE TREES MATTER
Jason Henning, research urban forester, Davey Institute,
discussed the idea that large, mature trees are important
for the ecosystem services they provide, more so than
smaller trees, at the Tree Canopy Conference at Haverford
College in Philadelphia.
"In the city of Philadelphia an i-Tree analysis showed that
the largest 10 percent of trees made up 41 percent of the
city's canopy cover and accounted for 74 percent of the
carbon stored by trees," Henning said.
Henning reported it would take nearly two dozen newly
planted red maples to make up for the removal of a single
mature tree in terms of ecosystem services. Part of his
presentation also dealt with how to effectively communicate
these benefits to city councils and concerned citizens.
The presentation caught people's attention and sparked
quite a bit of follow-up discussion.
"It's a great conversational conference," Henning said.
"People really care about trees and why trees are important
to what we do."
Jason Henning discussing why large, mature trees matter at
the Tree Canopy Conference at Haverford College in Philadelphia.
