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| Send us your tree/plant questions asktom@parkwaypartnersnola.org We will post your question and the answer. |
April 2007
I see a lot of trees with partially damaged bark, cut through by work crews using trees for leverage to pick
up house-clearing debris with back hoes or tractors. ...if a tree has it's bark broken all the way around will it
die? What about partial gouges in the Live Oaks? To what degree is the weight of these work vehicles
running over the land around the base of trees damaging to the root structures?
Colleen
Physical injury to the trunk of the tree is a terrible thing. The phloem is a critical layer of tissue that is just
below the bark. If bark has been broken off all the way down to the wood, then the phloem is gone. If the
wound occurs all the way around the tree that represents a complete interuption of the phloem and the
tree will surely die. How much is too much? Different species, and trees in different stages of health, can
withstand different levels or percentages of the bark being removed. Live Oak is more hearty than most
species. The amount of bark popping that will kill the tree is a wait and see thing. I have seen Live Oaks
with such extensive bark popping that I am pessimestic about their survival.
Soil compaction is a very significant problem that was caused by the heavy equipment movement.
Remember this, tree roots breathe. They get their air from the pore spaces in the soil. The pore space is
significantly and perminately eliminated by soil compaction. Fewer smaller air spaces equals less air
movement so tree roots suffocate. But this is only part of the problem. A healthy soil is a complex
association of organic and inorganic componants both living and non-living including the mineral
componemts of sand silt and clay, and all the microorganism, worms, bugs, fungi, bacteria,amoebas, etc.
The floodwaters that stayed on our soil for two and three weeks killed almost all of the living breathing soil
organisms. In the good/bad scheam of things this is bad.
Because of this, I think that the most important thing we can do for the health of our existing trees is to
address the health of the soil. Mulch the root zone with a top dressing of 2-3" of composted wood chips.
Provide some of the essential soil fungi with a mycorrhizae treatment such as MycorTree. Aeriate the soil
to improve the air movement. The best technique for soil aeration is an air spade or air knife. This is a high
pressure air tool that can move the soil without adversely affecting woody roots. Experienced arborists
will be able to use this tool to incorporate the mycorrhizae and organic matter into the soil.
That is a short answer to a complex situation. Fact of the matter is that I'm just evolving in my
understanding of the situation. If anyone can add to this understanding please do so.
I hope that is a help. Good luck with your trees!
Tom Campbell
I see a lot of trees with partially damaged bark, cut through by work crews using trees for leverage to pick
up house-clearing debris with back hoes or tractors. ...if a tree has it's bark broken all the way around will it
die? What about partial gouges in the Live Oaks? To what degree is the weight of these work vehicles
running over the land around the base of trees damaging to the root structures?
Colleen
Physical injury to the trunk of the tree is a terrible thing. The phloem is a critical layer of tissue that is just
below the bark. If bark has been broken off all the way down to the wood, then the phloem is gone. If the
wound occurs all the way around the tree that represents a complete interuption of the phloem and the
tree will surely die. How much is too much? Different species, and trees in different stages of health, can
withstand different levels or percentages of the bark being removed. Live Oak is more hearty than most
species. The amount of bark popping that will kill the tree is a wait and see thing. I have seen Live Oaks
with such extensive bark popping that I am pessimestic about their survival.
Soil compaction is a very significant problem that was caused by the heavy equipment movement.
Remember this, tree roots breathe. They get their air from the pore spaces in the soil. The pore space is
significantly and perminately eliminated by soil compaction. Fewer smaller air spaces equals less air
movement so tree roots suffocate. But this is only part of the problem. A healthy soil is a complex
association of organic and inorganic componants both living and non-living including the mineral
componemts of sand silt and clay, and all the microorganism, worms, bugs, fungi, bacteria,amoebas, etc.
The floodwaters that stayed on our soil for two and three weeks killed almost all of the living breathing soil
organisms. In the good/bad scheam of things this is bad.
Because of this, I think that the most important thing we can do for the health of our existing trees is to
address the health of the soil. Mulch the root zone with a top dressing of 2-3" of composted wood chips.
Provide some of the essential soil fungi with a mycorrhizae treatment such as MycorTree. Aeriate the soil
to improve the air movement. The best technique for soil aeration is an air spade or air knife. This is a high
pressure air tool that can move the soil without adversely affecting woody roots. Experienced arborists
will be able to use this tool to incorporate the mycorrhizae and organic matter into the soil.
That is a short answer to a complex situation. Fact of the matter is that I'm just evolving in my
understanding of the situation. If anyone can add to this understanding please do so.
I hope that is a help. Good luck with your trees!
Tom Campbell
| Parkway Partners - 1137 Baronne, St., New Orleans, LA, 70113 - 504-620-2224 |
February 2008
Hi, Tom,
We all really appreciate your work and your willingness to share knowledge.
1. Most important question: Can you help me find a BULK source for composted tree bark? Or other bulk
compost?
1. Composted wood chip ( not composted bark) is the preferred material for
mulching around trees. This material is available from several of the
larger arborist companies in town.
2. Should we aeriate the whole area where heavy machinery was used vs just the area closer to the trees?
Do "bobcats" count as heavy machinery--as opposed to front loaders, etc.?
2. Aeration is an important technique for remediating soil compaction
anywhere in the root zone, not just close to the tree. Bobcats with tracks
are much a better than ones with wheels in minimizing the soil compaction
but yes they do compact the soil and depending on the amount of movement in
the area it may well be necessary.
3. Is there a place to rent soil aeriators?
3. I do not know about renting soil aerators.
4. My yard ended up with ruts and uneven places in it. I intend to use
river sand to smooth it out. If that is what you are talking about then
yes, it is fine. Larger amounts of fill can restrict air movement and in
those cases the courser the material the better because the larger particle
sizes have larger pore spaces through which the air can move.
4. Does it really make a big difference whether we use spillway sand or pump sand to fill in our "FEMA
gouges", in the bigger picture?
with many thanks--Shirley
I hope this helps.
Tom Campbell
Hi, Tom,
We all really appreciate your work and your willingness to share knowledge.
1. Most important question: Can you help me find a BULK source for composted tree bark? Or other bulk
compost?
1. Composted wood chip ( not composted bark) is the preferred material for
mulching around trees. This material is available from several of the
larger arborist companies in town.
2. Should we aeriate the whole area where heavy machinery was used vs just the area closer to the trees?
Do "bobcats" count as heavy machinery--as opposed to front loaders, etc.?
2. Aeration is an important technique for remediating soil compaction
anywhere in the root zone, not just close to the tree. Bobcats with tracks
are much a better than ones with wheels in minimizing the soil compaction
but yes they do compact the soil and depending on the amount of movement in
the area it may well be necessary.
3. Is there a place to rent soil aeriators?
3. I do not know about renting soil aerators.
4. My yard ended up with ruts and uneven places in it. I intend to use
river sand to smooth it out. If that is what you are talking about then
yes, it is fine. Larger amounts of fill can restrict air movement and in
those cases the courser the material the better because the larger particle
sizes have larger pore spaces through which the air can move.
4. Does it really make a big difference whether we use spillway sand or pump sand to fill in our "FEMA
gouges", in the bigger picture?
with many thanks--Shirley
I hope this helps.
Tom Campbell