Using Cambistat to Help Declining Trees
Mature trees are valuable assets to a landscape, but there are a
wide variety of stresses that may lead to their gradual decline.
Some of these include:
- Soil compaction
- Over watering
- Drought
- Repeated defoliation from insects or fungi
- Herbicides used for broadleaf weeds
- Root loss from construction or gardening activities
- Over pruning of live tissue
- Diseased roots or other ailments
Cambistat changes where energy is spent in a tree, shifting resource
allocation away from the canopy to other systems. Tree decline may
be a signal the root system is unable to support the existing canopy,
and dieback occurs until an equilibrium is reached. Conservative
energy alloction to the canopy is consistent with how a tree should
respond to recover from the decline, but Cambistat should rarely
be used alone to accomplish this.
Without treatment or relief from the stress, Cambistat may not
be effective. It is important to know the history of the tree and
determine the issues affecting it. Trees declining rapidly are not
good candidates for Cambistat because the treatment takes a year
or two to be effective. For help please contact
Rainbow Treecare Scientific Advancements.
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treated 1989
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2001 |
In this series of photographs, this white
oak was treated with Paclobutrazol. This tree had been slowly
declining for many years.
Photos courtesy of Gary Watson - Morton Arboretum
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Soil Compaction
A Leading Cause
of Tree Decline
Soil compaction is a leading cause of tree decline and is often
overlooked by arborists. Its effect on trees is insidious, and is
almost always fatal over time. Depending on the health of the tree
at the time of compaction and the severity of the compaction, trees
can live many years by living on stored reserves. In essence, a
tree trying to grow in compacted soils will be made inefficient
at making energy, thus it will make less energy than it needs. When
reserves run out, the tree dies. |
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How Soil Compaction
Hurts Trees
A tree is constantly generating fibrous
roots. They weave their way through the soil taking up moisture,
oxygen,and other elements the tree needs to survive. When
the soil is compacted, it has 2 effects. First it inhibits
these fibrous roots from growing. The tree loses its ability
to effectively mine the soil and absorb what it needs. The
second effect is that the soil loses its ability to exchange
gases or dry out. Most trees absorb the oxygen they need to
metabolize food through their root systems, and without oxygen
exchange, the tree begins to slowly suffocate.
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Soil
compaction is common in urban sites as well as in construction
areas. Do not treat trees living in compacted
soil with Cambistat without doing soil
replacement therapy. |
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