Decisions, Decisions
Stumps can be eliminated from the landscape in a number of ways. A major decision point is
whether to completely extract and remove the stump, or leave some portion or all of the stump in-place
in the soil. One low impact alternative includes cutting the stump low and level so a mower or other
vehicle can drive over. Another low impact alternative is leaving a high stump for use as a weathered
planter, temporary seat or table.
If a stump will be removed from a landscape, the next decision point is whether to extract the
stump whole or in large pieces, or to break the stump apart into small pieces where it sits. In-place
stump removal usually does not pose an equipment intensive demand on landowners, nor risk extensive
landscape disruption as extraction. Stump extraction usually requires plenty of space because of the
power requirement of the equipment used and the physical size of the stump to be transported off-site.
What is Best?
Stump removal processes can be generically described as: dig, push up or yank stump out of the
ground; break the stump up into various sized pieces; burn what wood you can; accelerate the chemical
(~25% faster) or ecological (~50% faster) degradation and decay process; or, do nothing.
Ecological Values
Stumps are a food source and a habitat which is difficult to find in many community landscapes.
The creatures which inhabit and use the decaying stump change as the stump changes. Energy concentration
in a decaying stump represents a rare and essential resource to a number of animals and micro /
meso-organisms. If a stump can be simply left in-place and not disturbed, interesting things can happen,
especially when the stump is surrounded by a healthy soil. The pieces and chips of a stump can also be
used to enrich the site and provide unique, wood centered habitats.
Soil Subsidence
However a stump is removed from a site, the space it occupied will be left behind -- the stump
hole excavation (calera) and root channels of various sizes and lengths. As soil subsides, new mineral
soil will need to be applied to the site. Small layers of soil can be applied and then washed into the soil
openings or depressions. Be careful to not use water or tamping to compact new soil into old positions.
Because the stump and roots will take many years to finally decay away, many years of vigilance will be
needed to fill-in areas. Stump and root decay near structures or pavements may require soil stabilization
to prevent damage. If roots or stumps were pushing damaging structures when alive, wood decay will
lead to additional damage. After you have declared victory on a stump and walked away, periodic visits
to minimize liability risks and repair unexpected problems will still be required.
Future Site Use
The site which remains after stump removal will be dominated by decay processes for a number
of years. Once the decay process is functioning well, a new tree can be planted near the site. Planting
should be completed outside the area impacted byb the removal treatment. The cause of death, or need
for removal of the original tree, needs to be considered in both species and site selection for a new tree.
The same resource limitations (including pest problems) can impact the new tree as they constrained the
old tree, unless changes are made. Planting back into the identical location as the original tree is possible
if the old stump is broken and shattered enough to allow the new tree to colonize the native soil.
New soil can be used for fill in the stump excavation or caldera, but multiple openings or connections to
the surrounding native soil through the old stump site are essential. Usually several years are allowed to
pass, with rapid decay progression, before a new tree is planted in the same location. Do not plant in
only the wood chips from a stump pushed back into the caldera, as resource fluctuations can be severe
for a new tree, as will access to the new roots by pests.
Conclusions
There are many ways to deal with stumps in a landscape. The techniques involved are centered
around soil weakening or loosening, excavation, extraction, and/or reduction. Reducing the stump
through grinding or chipping is the most prevalent technique used in a well managed, modern landscape
operation. Other means of mechanical or natural reduction can be used. For most landscape systems
and objectives, quickly recycling the resources and space occupied by a dead stump is critical.
Decisions, Decisions
What is Best?
Ecological Values
Soil Subsidence
Future Site Use
Conclusions
