Page 23 - Moving the Earth_ The Workbook of Excavation

LAND CLEARING AND CONTROLS

LAND CLEARING AND CONTROLS 1.23

FIGURE 1.17 Stump removal with shovel dozer.

the stump, cutting and tearing the roots, then rolled back, lifting the stump from the ground. If it
falls off, the bucket is dropped to contact it and to roll it out of the ground. If it stays in the bucket,
it can be carried to a pile or loaded directly on a truck.
The high lift gives the dozer shovel excellent leverage for pushing over trees.
Bucket teeth are desirable for stumping, as they aid penetration, get a better grip on the stump,
and are useful for knocking dirt off the ball and for raking out roots.
Methods of handling stumps with a dozer bucket are described in Chap. 16.
Selection of Machinery. Big machines, and special machines, greatly reduce time, effort, and
breakage in clearing work, and should be used whenever a job is large enough to justify their pur-
chases or hire. Stumps that can be knocked right out of the ground may be removed at the rate of
one a minute or better; moderately resistant ones may take 2 to 5 minutes; and those which are
definitely oversize may take an hour or more. It is easy to see the time that can be saved by applying
overwhelming power.
A good clearing team may be made from a heavy tractor with a stumper, assisted by a smaller one
with a shovel dozer. If these machines work together closely, the stumper can devote its entire time
to breaking out the big ones, while the dozer takes out small stumps, knocks down brush, finishes
off loosened stumps, piles and removes them, and smooths the ground.

Revolving Shovels. The backhoe is probably the best stumper among the shovel attachments.
Usually, the operator tries to take the stump by a direct pull first. If it resists, it can be weakened
by chopping roots on the far side and by trenching at the sides. Except in the case of very large
stumps, digging and removal can be done from one position. It may be necessary to put blocks
against the tracks to prevent the shovel from dragging toward the stump when power is applied.
A dragline is used in the same manner but is less efficient at chopping roots and does not have
as strong a pull. However, it can often take out a number of stumps without changing position,
and is able to backfill the holes and grade the area at the same time.
A power shovel with a dipper stick is used in somewhat the same manner described for a dozer
shovel. It has more penetration and can trench to cut roots more readily but is less maneuverable.
The hoe and the dipper are more effective than dozers in rocky ground and among interlocked
stumps, as they can apply their power in smaller spaces. It is often necessary to devote time to dig-
ging out rocks before the stump can be attacked. If the roots are strongly entrenched in bedrock
or oversize boulders, the rock may have to be blasted before the stump can be pulled.
Rippers and Scrapers. Rippers may be used to cut stump roots and to pull out stumps directly. With
two teeth (or one tooth mounted at the side), the ripper can cut roots close to the trunk on all sides.
The tractor is then backed with raised teeth to catch the far side of the stump, then forward to pull it
over. Another back pass enables the operator to get a tooth under the stump, and lift and roll it out.
Scrapers (nonelevator models) can take out small and low stumps, but this involves compli-
cated maneuvering and danger of getting the stump jammed in the bowl.

Close Quarters. Stumps are often so located that uprooting them would damage pavement or
buildings. Such a stump may be removed in chip form, with little disturbance, by a carbide-toothed