SP-12-22 pre-skidding of tree lengths with a horse
After felling, delimbing, and topping, tree lengths are pre-skidded to a strip road using animals, and
most commonly draught horses. Different breeds are available in different regions, but
the most popular are heavy breeds like French Percherons, Belgian Ardennes, or
Italian TPR.
Capacity to work in
dense stands and narrow corridors, inaccessible to mechanical vehicles.
Capacity to handle
soft or steep terrain (provided extraction proceeds
downhill).
Very low soil and
stand impacts, because the animal has neither the size nor the power of a
machine, and therefore it can never resort to brute force against an
obstacle, but it must rather use brains and technique.
Safety for the
operator, who can control the horse at
a distance through voice commands.
Comfort for the
operator, who is spared noise, vibration, exhaust gases, heavy cable pulls
and tiresome walks on uphill grades (since he can ride the horse if
the walk is too hard).
Competitive cost on
intermediate pulls (between 50 and 100 m), which are too long for
direct winching
and too short for cost-effective cable yarding.
Limitations,
thresholds:
The system is suitable for young trees only, as obtained from first
and second thinnings, or to coppice harvesting operations.
The size of older trees is generally too large for an animal to move them
without preliminary crosscutting
Distance must not
exceed 200 m. Best results are obtained on shorter distances, between 25
and 100 m.
Extraction must
proceed on flat terrain or downhill slopes, with a maximum gradient of
50%. Experienced animals and drivers can safely handle steep terrain.
Draught animals can
only work 5 to 6 hours a day. Operators working longer hours
generally keep two animals and rotate them.
Main use
Animal pre-skidding is
still competitive with other mechanized pre-skidding systems
(winches,
mini-skidders etc.), but it is rarely used in industrialized countries,
where it remains a specialist niche. The reason is in the small numbers
of horse loggers,
ready to accept the constant commitment imposed by animal care.