We've all heard the quote "You can't fight city hall". While this is not
always true, imagine trying to get the Federal Government to change its tune. This is exactly what we're up against
with the threat of Emerald Ash Borer (EAB).
Many tree care providers (us included) are advocating preventative treatments to spare as many trees as possible,
once the Emerald Ash Borer does arrive. Now this pest has been discovered in the Upper Peninsula of Michigan, so
that Lake Michigan no longer separates us from this intruder. The problem lies in the fact that the Scientific
Advisory Board to the Federal Government is disallowing these preventive treatments from sparing Ash trees from
the axe if they are in a quarantine zone. This zone is a ½ mile radius around any Ash discovered with E.A.B. What
this means is if some Ash tree is infested within a ½ mile away from your property and although you have diligently,
proactively cared for your Ash tree(s), it will be condemned to removal by the government.
A small group of Wisconsin Arborists, (us included) have sought to change this policy, only to find out that the
state of Wisconsin has no control over this. Indeed, if the state refuses to comply with the federal mandate, then
the entire state will be quarantined and no federal dollars will flow to the problem; an economic disaster. But is
this a hopeless situation? Our state officials think not. Their claim is that we have such a head start on the
potential problem, unlike Michigan, which was heavily infested before anyone noticed, that quarantined removals
should be a very limited occurrence. In the meantime, we are hopeful that ongoing research will alter the Federal
Government's position on this.
We continue to advocate and urge everyone with Ash trees to continue preventative treatments. After all, if hundreds
of arborists are treating thousands of trees, we could theoretically substantially reduce the likelihood of local
outbreaks of E.A.B. It should also be noted that the most likely war for E.A.B. to enter an area is through firewood
movement. It is therefore recommended that firewood not be transported out of a local area. Procure your wood and
use that wood in the same general area. This particularly applies if you have a summer home or a camping outing, not
to drag firewood all over the state.
We will continue to follow this situation closely and keep our clients informed of the latest information.
Causes of Tree Aging
It is clear that old trees behave differently than your trees. What is the basis for these differences? Six
primary causes of tree aging have been explored by researchers. Each cause has its own proponents and detractors.
The "real" answers about tree ageing probably are a combination of ideas.
Cause 1: Reduction in Photosynthesis
Photosynthesis is reduced in older branches by approximately 22 percent. Increased stomatal closure in the
leaves, coupled with increased transport resistance in vascular tissue, has been attributed to this reduction
Cause 2: Increased in Sapwood Respiration
Less food is generated for the amount of living tissue maintained. Living biomass accumulates, while food
production declines in the old tree.
Cause 3: Decline in Soil Resources
As fewer essential resources are present, more stress aging should occur.
Cause 4: Increase in Transport Path Length and Complexity
Old trees have approximately 22 percent less food available than young trees because the old ones have
greater resistance in water movement.
Cause 5: Detrimental Genetic Mutations
As trees age, cell division ability slows and becomes less efficient. Errors in genetic materials
lead to rogue proteins and cell death.
Cause 6: Reduced Defenses
Old trees generate more secondary compounds than young trees. As more secondary materials are
generated for the living volume maintained, less food is left for growth.
Treatment 1: Providing Resources
Maintaining a supply of organic matter is essential for soil health and old tree performance.
Improving the biological health and physical features of soil is critical: improving aeration, ensuring
adequate drainage, and alleviating compaction. Continual small dosing of essential elements, especially
nitrogen, is required to push carbon allocation priorities back toward the crown.
Treatment 2: Giving More Space
Old trees are less able than young trees to effectively compete with surrounding landscape plants.
Mulching to gain separation distance and maintaining a clear zone around the trunk is important for
Treatment 3: Improving Structure and Support
Old trees are burdened by their mass, reach and size. Reduction of tree reach, extent and mass above ground
can reduce risk of structural failure and improve transport path problems. Occasional crown reductions are
a lese radical means of accomplishing similar results. Emphasis should be placed on minimizing the number
of branch orders, shortening branch length, and reducing branch weight.
Supporting tree mass and controlling movement with a well-designed cable, brace, or other support system is
also a way to conserve old trees.
Treatment 4: Minimizing Stress
Spot attacks and systemic problems become more important to identify and treat in a timely fashion with aging, both
because of the old tree's diminished biological functions and its greater perceived value.
What Causes Fall Color?
Fall color in a tree's leaves is one of the results of the tree's yearly cycle of food production and food storage.
This food production occurs in a process called photosynthesis, which takes place mainly during the spring and
Chlorophyll is constantly being produced and destroyed within leaves, and it gives them their green color. Leaves
remain green when the production of new chlorophyll is equal to the destruction of old chlorophyll, thus creating
a balance. As the days become shorter and cooler in the fall the amount of sunlight available for leaves to absorb
decreases. With the corresponding cooler temperatures, the production of new chlorophyll slows down, and the amount
of the pigment found in leaves is reduced. As a result, their green color begins to disappear.
As chlorophyll fades, other pigments in a tree's leaves gain prominence. These pigments, carotenoids, anthocyanins,
and tannins, are the basis for the vivid color changes in leaves before a tree becomes dormant for the winter.
The Air Knife
This tool conjures up various visual images:
"The air is so thick you could cut it with a knife"
"Another name for the swords used in Star Wars."
"Make believe knife fighting, similar to air guitar"
It is a very unique toll that actually does cut with air pressure. This device utilizes super sonic air
speeds to excavate soil with out even the slightest nick to even the most delicate roots. Cassity Tree
Service utilizes this tool for many various root, soil, or trunk base or planting depth problems.
Deep or buried root systems have been causing problems for arborists for decades. Though it is often referred
to as "planting too deep" the cause of buried root systems is not limited to the planting process. Some times
no one knows what causes the problem or how it should be solved, but one thing is clear - many landscape trees
Previous Arbor News Publications
The Effects of Drought on Trees
By Susan Tangen
If you have a lawn around your house or a flower bed in your back yard, you may know the effects of drought
on the turf and the flowers. But, do you know the effects of drought on trees?
When there is an extended period without sufficient amount of rain, the trees try to conserve water by closing
the stomatas (pores on the underside of the leaves). When this occurs, photosynthesis for food production and
growth slows or ceases. The leaves may be undersized, wilt, yellow, curl or crinkle, turn brown on the margins
or prematurely senescent and drop.
After the tree fails to conserve water by the previous means, feeder roots dieback. The result is crown dieback
and general thinning of the canopy. Furthermore, the tree becomes stressed and makes it more susceptible to
opportunistic pathogens. Boring insects may invade the tree or fungus may penetrate the bark, wood or cambium
zone which can cut off the water supply to the tree.
Although all trees are at risk during long periods of drought, some are more prone to the effects than others.
New transplants are highly vulnerable to drought stress and supplemental watering is necessary. However, don't
forget about the mature trees, they are also suffering. Unfortunately, the after effects of the drought are
likely to ripple for the next 3 to 5 years and only the trees that are the strongest will survive.
There are a couple things you can do to prevent or reduce the effects of drought stress. The first thing is to
water. Most trees require an inch of water every 7 to 10 days. If nature does not provide it, you must supplement
it by watering. Water to a depth of 6" and repeat when dry. A soaker hose or irrigation system around the drip
line of the tree works well. Secondly, remove turf and apply organic mulch over as much of the drip line as possible.
Turf uses a large portion of water before the tree even has a chance to use it. By removing the turf and applying
mulch, more w3ater will be taken up by the tree and less will be lost due to evaporation. Apply 2" mulch for clay
soil and up to 4" for sandy soil.
So, the next time you reach for the hose to water the lawn for flower bed, think about the trees and the effect
drought has on them
This newsletter has adapted articles from the publications of the following organizations in addition to our original pictures and stories.