Yard
and Garden
April
11, 2015
Q. I
have an old tree stump in the place I was thinking of putting a compost
bin. Will it hurt to just build compost over the stump and hope it rots
or should I dig the stump out?
A.
The stump may cause some problems as you try to turn the compost, or it may
form a back-stop to help you turn the compost. The pile of decomposing
material, properly moistened around the stump should speed the decomposition of
the stump. Another option is to cut the stump as close to the ground as
possible so that it is less a hindrance as you turn the compost. To speed
the decomposition of the stump you can drill holes in the stump to allow even
more contact with the decomposing materials of the compost and the
microorganisms that will cause the decomposition of the stump. Use
one-half in to one inch spade bits on a drill to make the holes.
However, since you said “old” stump I wonder what kind of tree produced the
stump. If the tree was a juniper or Arizona cypress tree the wood is very
resistant to decomposition and may take longer to decompose than most other
tree stumps. In that case cutting it out of the way and drilling the
holes may make even more sense. If the tree was a cottonwood or willow,
the wood will decompose quite rapidly once the composting environment
develops. Frequent additions of high nitrogen materials such as manure or
kitchen scraps and water will help any stump decompose. The end product
of the decomposition of the stump will be good compost along with the compost
formed from other materials.
If it is important to get rid of the stump quickly, you can dig it out, cutting
the roots and then pulling with a vehicle or with a pulley system. Most
trees do not have deep root systems that will make removal difficult. I
have heard of people burning the stumps as well. If the stump is in a
location where burning is not hazardous to structures and surrounding
vegetation that is an option, but be very careful. To make the burning
more complete you
can
drill the holes described above and fill the holes with kerosene or diesel
fuel. Do no use gasoline or lighter fuels. Allow the fuel to soak
into the wood, perhaps refilling the holes several times over several
weeks. Once the wood has absorbed the fuel ignite the stump. Be
sure the area around the old stump for a considerable distance is free of
combustible materials and watch over it carefully. Do this when there is
no wind forecast for several days. It may take quite a while for the
stump to completely burn and wind could carry embers to areas where the fire is
not wanted. Personally I prefer the idea of turning the old stump into
compost. It is safer and the end product is more useful, but composting
will take longer.
Send
your gardening questions to Yard and Garden, Attn: Dr. Curtis Smith, NMSU
Agricultural Science Center, 1036 Miller Rd. SW, Los Lunas, NM 87031. You may
also send to cwsmith@nmsu.edu or leave a message at https://www.facebook.com/NMSUExtExpStnPubs. Curtis W. Smith,
Ph.D., is an Extension Horticulture Specialist, retired from New Mexico State
University’s Cooperative Extension Service. NMSU and the U.S. Department
of Agriculture cooperating.
