The cold and snowy conditions in Connecticut this winter have made me
look for better ways to do my necessary
orchard pruning. I will go into some detail here with my experience, because I
have not seen reports from others with electric pole pruners.
Pneumatic pruners, run off a small gasoline-fueled air compressor, did
an acceptable job when there was no
snow on the ground, and temperatures were mostly above freezing. I move the
compressor rig around in a garden
cart. Last year I moved it on a plastic sledding toy, while I wore snowshoes.
This winter, before snow became a
nuisance, ice-formation in the triggering mechanism was wasting a lot of my
time, so I looked into electric pruners.
My trees' fruiting zone is between about 6 and 8 feet above ground, so
a significant amount of the work is just
a bit of a stretch for hand-held electric pruners, and I am not immune to the
effects of this repetitious weight-lifting.
A pole pruner, I thought would make the job easier. Also, it would not involve
an air-hose that tangles in the dropped prunings. And it would not require my
patient persistence with starting a stubborn engine on cold mornings.
I found a pole pruner, bought it, and went eagerly back to the orchard
on a cold day. I could not keep my hands
warm in gloves, so I wore thick mittens. With the pole in place, the blade is
opened and closed by pressing a small button on an attachment that can slide
up and down the pole. The gun-like trigger on the pruning unit itself is not
used when the pruning unit is attached at the end of the pole. Locating the
button when wearing thick leather mittens was unreliable, so I fabricated a
button extension, which, when glued onto the small, provided button, was easy
to
find through the thick mitten. Back in the orchard, the new pole pruner was
now everything I had expected. But after several hours, I was noticing pain in
my left arm and shoulder. When I thought about it, that made sense; the left
arm was carrying most of the weight, while the right arm was mostly only
steering.
The next day I gave my sore left shoulder a rest. I could have just
switched to supporting the pole's weight with
my right arm, and steering with the left. But that might leave me with two
complaining arms on the following day. The
pruner is not terribly heavy…2.8 pounds, and the pole, mostly of carbon fibers,
adds only 2 pounds to the combined weight. The apparent heaviness of the pruner
is a result of a principle of physics. That principle is called the Moment of
Inertia. (Brief you- tube explanation here:
http://www.youtube.com/watch?v=uyU25DdONjo The effective weight of the pruner
increases as the SQUARE of the distance between the handle-end of the pole, and
the pruner at the far end. My pole puts the pruner 4 feet from the handle end.
If my supporting hand is at 3 feet from the end, a 2.2 pound pruner would feel
like 19.8 pounds when the pole is horizontal (less as the angle approaches
vertical.)
I figure I could reach most of my pruning cuts with a pole shorter than
the four feet this one is. Four feet is the
shortest length offered by the manufacturer. To shorten my pole requires
removing parts at one end or the other, then replacing them after a section of
the carbon fibre pole is cut out. I could find no company rep who could
describe how either end section could be removed. They appeared to be either
glued, or extremely tight-fitting.
Instead, I removed the pole from the pruning unit, and removed the on-off
button and its attached slider from the pole,
tied to it a string loop, and hung it around my neck so that it could be
operated with a mitten-covered left hand, as I
used the pruner, w/o pole, in my right hand. As it turned out, a day's use of
the under three pound pruner, held overhead, directly with my right hand, while
operating the switch with the left hand, was more weight-lifting than I wanted
to repeat. I should note that I would not have needed to operate the switch, if
it had been warm enough to wear gloves, rather than mittens. Mittens do not
allow use of a single finger through the trigger guard.
Today, after some trial and failure, I found a way to remove the top
end pieces from the pole, sawed off 15 inches
of pole, and replaced the end pieces. The slider switch was also returned to
the pole. I have now tested the adjusted
tool and found it to be significantly more friendly.
There is one more observation that I think explains why my shoulders
complain after some hours of pruning.
The batteries and most of the other electronics associated with the pruner are
carried in a backpack whose weight
is a bit under 7 pounds. The pack has two straps that run over the shoulders,
and a wide "velcroed" belt run around
the belly. If the pack is worn outside a sleeved coat, raising of the arms
tries to lift the pack, but meets resistance
from the belt wrapped around the coat. It is as though the pack is held down by
friction and folds in the coat. My
conclusion is that the battery pack should be strapped on loosely over the
shoulders, and tightly around the waist
BEFORE getting into any un-stretchy clothing that will be lifted when reaching
overhead. Finally, an extended arm,with
a hand-held 2 pound pruner will feel like 12.5 pounds, assuming a 2.5 foot arm.
David Kollas
Kollas Orchard, CT
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