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Elm Trees Epidemic
Lindsey L. |
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| Look out your window; what most of you will see are trees. Some birch and mostly winter green. Could you believe that around the time of Joseph Brown's life he would look out the window and seen trees that looked like something out of a modern day doctor Seuss book. These whimsical trees were called Elm trees. These trees known as Americas first symbol of freedom grow mostly in moist climates. New England weather is perfect to nurture an elm trees living habits. Elm trees have bark that is gray or a dark brown. The bark on live trees ranged from smooth to flakes and ridges. Some elm trees such as the English elm grow flowers that open in late February. Some trees also like English elms have fruit that grow and are ripe by late march. Elm trees have unique leaves with a rough green layer on the outside. There is a long pale green veil down the middle of the leaf. Some other forms of elms like the smooth leafed elm have a light green and smooth outside with no other color present but they too also have a small fruit that grows in late March. This unique tree is native to nothern parts of Europe, Africa and Soth west Asia. The bark was often damp and used along with the trunk for docks, boats, coffins furniture and flooring for homes and places of work. Another common use for elm trees was no for what they produced but for what they hid. Elm trees were commonly grown on city streets blocking the sun for passing travelers. They were shaped like umbrellas to hide the travelers underneath. People would put them in their yards to block the sun in the summer time. Joseph Brown had many Elm trees in his yard they were probably there for this purpose. | ||
Elm trees were fast becoming a household use until 1930 where a disease formed in Ohio causing Elm trees to become infected by a rare beetle caring the disease. The disease infected the bark and roots of the tree and rooted the bark. This disease spread across the country to all the parts of the United States. The disease known as Dutch elm disease also spread through most of Europe and Africa where the Elm tree is native. Dutch Elm disease wiped out almost the entire population of Elm trees in the United Kingdom. The Disease can be diagnosed by only taking a fragment of Bark to a lab. There is no other way to accurately find out if a tree has Dutch elm disease. There are however symptoms and traits of a tree that is infected by the disease. The wood under the bark will start to root and the leaves will die and turn yellow if the tree becomes infected with the disease. The tree may give off a putrid odor smell. Even though Dutch elm disease is the most Know disease know to Elms it is not the only. There is a disease that is just as dangerous and wide spread as DED. This disease is called Phloem Necrosis or PN for short. Even though PN is a relative disease to DED they are very different, For instance DED is caused by a fungus carried by the Elm bark beetle and PN is caused by a virus that infects the roots of the trees and the bark through the carrier that is a leafhopper. Another difference is that DED could infect all types of trees un- like PN, which only infects American elm and Winged Elm. The disease is found all over the world where Elm trees are found. It is a very common disease like DED to the trees it infects. There is only one sure way to know if your elm tree has PN that is testing. Remove a strip of bark from the trunk of the tree and remove the discolored layer of wood from beneath the bark, put the sample in a vile that is sealed. If the wood is infected when removing it from the vial the sample should give off a putrid odor. Another way to tell if the tree is possibly infected by PN cut through the bark on the tree if the tree is susceptible to PN the wood will be yellow and discolored. You can control the spread the disease by spraying the dead tree with a mixture of pesticides and different insect repellent. This will keep the leafhopper from receiving the virus from the dead tree. Another way to prevent both DED and PN is to burn the dead tree so the virus will be killed and the leafhopper will have no chance to carry the virus to uninfected trees. Both diseases of PN and DED is still found today even though precautions are taken to prevent the spread of the disease it is still found in along the northern seaboard as far north as Vermont an New York and as far south as Virginia and Mississippi and west as far as Colorado but any other states our countries are still at risk. |
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If you think that elm trees are only
used for their bark and wood that would be a wrong assumption. Elm
trees have many other useful parts of their
trunk
and branches as well. Elm trees produce flowers, which bloom in late
February
in parts of the united state. This only applies to some Elm trees
others do not
have flowers that bloom. Another trait to the Elm tree is that it can
produce
fruit. The fruit will ripen in late march. Again this only applies to
some Elm
trees other do not carry any fruit. Joseph Brow would not have been
around at
the time that DED was found so he would have no experience in tree
maintenance.
The Elm trees started dying in the 1930’s this was 35 years after
Joseph died.
The Elm trees were an important part of American History they are how
and why
almost every town or state has a min road named Elm street, drive,
avenue or
any other form of passage. Elm trees made an impact on the environment
they
made an impact on the culture of the United
States. |
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 source -http://www.uafortsmith.edu/attach/Arboretum/AmericanElm/AmericanElmTree.jpg This picture of an elm tree shows different characteristics such as dark brown bark and large bush like banches.
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BibliographyBooks:
Rutherford Pait, 1001
questions answered about trees, 1959, Binghamton, N.Y , by
Vail-Ballou
press inc. Website: Eliminofo@americanelm.com,
2/15/05 www.firstscience.com
,2/9/05 |
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